The document describes a finite element method for numerically simulating the launch of an offshore structure jacket from a barge. Software programs like StruCAD*3D and SACS can be used to model the barge-jacket system and calculate the jacket launch process. The method involves establishing coordinate systems, modeling the barge and jacket geometry, calculating hydrodynamic forces, and solving the equations of motion to obtain the motion of the barge and jacket over time during the different phases of launch. The output provides details on the position, velocity, acceleration and interaction forces acting on the barge-jacket system throughout the simulation.
Dynamic modelling and optimal controlscheme of wheel inverted pendulum for mo...ijctcm
Unstable wheel inverted pendulum is modelled and controlled deploying Kane’s method and optimal
partial-state PID control scheme. A correct derivation of nonlinear mathematical model of a wheel inverted
pendulum is obtained using a proper definition of the geometric context of active and inertia forces. Then
the model is decoupled to two linear subsystems namely balancing and heading subsystems. Afterward
partial-state PID controller is proposed and formulated to quadratic optimal regulation tuning method. It
enables partial-state PID to be optimally tuned and guarantees a satisfactory level of states error and a
realistic utilization of torque energy. Simulation and numerical analyses are carried out to analyse
system’s stability and to determine the performance of the proposed controller for mobile wheel inverted
pendulum application.
shehabi - A Classical and Fuzzy Logic Control Design and Simulation of a Long...Abdul Ghafoor Al Shehabi
This document summarizes the derivation of the equations of motion for an aircraft. It begins by defining the aircraft body coordinate frame and describing the forces acting on the aircraft, including propulsion, aerodynamic, and gravitational forces. Newton's second law is applied to derive vector equations for the translational and angular motion of the aircraft in the body frame. Further sections describe how to transform between different reference frames, including relating the aircraft motion to an inertial earth-centered frame. The nonlinear vector equations are presented and then linearized to obtain decoupled linear equations of motion. Overall, the document methodically derives the fundamental equations modeling the six degrees of freedom dynamics of an aircraft in different reference frames.
Prediction tool for preliminary design assessment of the manoeuvring characte...Enrico Della Valentina
This document describes the development of a prediction tool to assess the manoeuvring characteristics of a twin screw displacement yacht in preliminary design. The tool uses numerical simulations in MARIN's SURSIM software to evaluate how variations in rudder area, position, rate of turn, and metacentric height impact yaw checking, course changing, turning ability, and directional stability. Standard manoeuvres like zigzags and turning circles were simulated across a range of design parameters to provide sensitivity analysis and guidance for design improvement. The results of the simulations are presented and discussed.
THE INFLUENCE OF DRIVING AXLE LOCATION ON THE LATERAL FORCE OF VEHICLEIAEME Publication
The lateral force acting on the tires produces a side slip angle that affects the
directional stability of vehicle. This paper presents some research results of the
influence of driving axle location on the lateral force of vehicle with 4x2 wheel
formula when vehicle is turning. The single track dynamical models of FWD and RWD
vehicle while cornering are created. Based on these two dynamical models, the system
equations of motion built are enable to study the influence of driving axle location on
the lateral force. Some calculated simulation results are shown for illustration.
This document discusses autonomous formation flight control for aerial refueling missions. It models the dynamics of a KC-130J tanker and F-16 receiver in close formation flight. A control strategy is designed using a rotating reference frame attached to the wingman aircraft. The strategy aims to control the wingman's position relative to the leader through state error feedback between the aircraft. Specifically, it controls the lateral and forward distance between the aircraft in the level flight plane, as well as the vertical distance. The control system design decomposes the problem into inner loop attitude control and outer loop trajectory control of the formation geometry.
KOM - Unit 3 -kinematics of cam mechanismskarthi keyan
This document discusses different types of cam mechanisms. It defines a cam as a mechanical device used to convert rotary motion into reciprocating motion. Cams are classified based on their input and output motions as well as the type of follower used. Different types of cams include wedge cams, spiral cams, radial cams, and cylindrical cams. The document also discusses cam nomenclature and the different types of follower motions including uniform, simple harmonic, uniform acceleration/retardation, and cycloidal motion. Displacement and velocity diagrams are presented for different motion types.
М.Г.Гоман, А.В.Храмцовский (1998) - Использование методов непрерывного продол...Project KRIT
М.Г.Гоман, А.В.Храмцовский "Использование методов непрерывного продолжения решений и бифуркационного анализа для синтеза систем управления", Phil.Trans.R.Soc.Lond. A (1998) 356, 2277-2295
M.G.Goman and A.V.Khramtsovsky "Application of continuation and bifurcation methods to the design of control systems", Phil.Trans.R.Soc.Lond. A (1998) 356, 2277-2295
In this paper the continuation and bifurcation methods are applied to aircraft nonlinear control design problems. The search for the recovery control from spin regimes is based on the minimization of an energy-like scalar function constrained by the aircraft's equilibria conditions. The design of a global stability augmentation system for severe wing-rock motion is performed by using bifurcation diagrams for equilibrium and periodical modes. The nonlinear control law, which totally suppresses wing-rock motion, is derived, taking into account both local stability characteristics of aircraft equilibrium states and domains of attraction, along with the requirement that all other attractors be eliminated.
Dynamic modelling and optimal controlscheme of wheel inverted pendulum for mo...ijctcm
Unstable wheel inverted pendulum is modelled and controlled deploying Kane’s method and optimal
partial-state PID control scheme. A correct derivation of nonlinear mathematical model of a wheel inverted
pendulum is obtained using a proper definition of the geometric context of active and inertia forces. Then
the model is decoupled to two linear subsystems namely balancing and heading subsystems. Afterward
partial-state PID controller is proposed and formulated to quadratic optimal regulation tuning method. It
enables partial-state PID to be optimally tuned and guarantees a satisfactory level of states error and a
realistic utilization of torque energy. Simulation and numerical analyses are carried out to analyse
system’s stability and to determine the performance of the proposed controller for mobile wheel inverted
pendulum application.
shehabi - A Classical and Fuzzy Logic Control Design and Simulation of a Long...Abdul Ghafoor Al Shehabi
This document summarizes the derivation of the equations of motion for an aircraft. It begins by defining the aircraft body coordinate frame and describing the forces acting on the aircraft, including propulsion, aerodynamic, and gravitational forces. Newton's second law is applied to derive vector equations for the translational and angular motion of the aircraft in the body frame. Further sections describe how to transform between different reference frames, including relating the aircraft motion to an inertial earth-centered frame. The nonlinear vector equations are presented and then linearized to obtain decoupled linear equations of motion. Overall, the document methodically derives the fundamental equations modeling the six degrees of freedom dynamics of an aircraft in different reference frames.
Prediction tool for preliminary design assessment of the manoeuvring characte...Enrico Della Valentina
This document describes the development of a prediction tool to assess the manoeuvring characteristics of a twin screw displacement yacht in preliminary design. The tool uses numerical simulations in MARIN's SURSIM software to evaluate how variations in rudder area, position, rate of turn, and metacentric height impact yaw checking, course changing, turning ability, and directional stability. Standard manoeuvres like zigzags and turning circles were simulated across a range of design parameters to provide sensitivity analysis and guidance for design improvement. The results of the simulations are presented and discussed.
THE INFLUENCE OF DRIVING AXLE LOCATION ON THE LATERAL FORCE OF VEHICLEIAEME Publication
The lateral force acting on the tires produces a side slip angle that affects the
directional stability of vehicle. This paper presents some research results of the
influence of driving axle location on the lateral force of vehicle with 4x2 wheel
formula when vehicle is turning. The single track dynamical models of FWD and RWD
vehicle while cornering are created. Based on these two dynamical models, the system
equations of motion built are enable to study the influence of driving axle location on
the lateral force. Some calculated simulation results are shown for illustration.
This document discusses autonomous formation flight control for aerial refueling missions. It models the dynamics of a KC-130J tanker and F-16 receiver in close formation flight. A control strategy is designed using a rotating reference frame attached to the wingman aircraft. The strategy aims to control the wingman's position relative to the leader through state error feedback between the aircraft. Specifically, it controls the lateral and forward distance between the aircraft in the level flight plane, as well as the vertical distance. The control system design decomposes the problem into inner loop attitude control and outer loop trajectory control of the formation geometry.
KOM - Unit 3 -kinematics of cam mechanismskarthi keyan
This document discusses different types of cam mechanisms. It defines a cam as a mechanical device used to convert rotary motion into reciprocating motion. Cams are classified based on their input and output motions as well as the type of follower used. Different types of cams include wedge cams, spiral cams, radial cams, and cylindrical cams. The document also discusses cam nomenclature and the different types of follower motions including uniform, simple harmonic, uniform acceleration/retardation, and cycloidal motion. Displacement and velocity diagrams are presented for different motion types.
М.Г.Гоман, А.В.Храмцовский (1998) - Использование методов непрерывного продол...Project KRIT
М.Г.Гоман, А.В.Храмцовский "Использование методов непрерывного продолжения решений и бифуркационного анализа для синтеза систем управления", Phil.Trans.R.Soc.Lond. A (1998) 356, 2277-2295
M.G.Goman and A.V.Khramtsovsky "Application of continuation and bifurcation methods to the design of control systems", Phil.Trans.R.Soc.Lond. A (1998) 356, 2277-2295
In this paper the continuation and bifurcation methods are applied to aircraft nonlinear control design problems. The search for the recovery control from spin regimes is based on the minimization of an energy-like scalar function constrained by the aircraft's equilibria conditions. The design of a global stability augmentation system for severe wing-rock motion is performed by using bifurcation diagrams for equilibrium and periodical modes. The nonlinear control law, which totally suppresses wing-rock motion, is derived, taking into account both local stability characteristics of aircraft equilibrium states and domains of attraction, along with the requirement that all other attractors be eliminated.
All possible questions - KINEMATICS OF MACHINERY / UNIT – ISenthil Kumar
This document contains 50 questions related to the topic of kinematics of machinery from various university exams. The questions cover topics like basic kinematic concepts, degrees of freedom, mobility criteria, inversions of linkages, transmission angles, classifications of mechanisms, common mechanisms, and straight line generators. Example mechanisms discussed include four-bar linkages, slider crank mechanisms, quick return mechanisms, steering mechanisms, and the Peaucellier straight line generator. Formulas related to transmission ratios and torque calculations for mechanisms like Hooke's joint are also included.
M.Goman et al (1993) - Aircraft Spin Prevention / Recovery Control SystemProject KRIT
М.Г.Гоман, А.В.Храмцовский, В.Л.Суханов, В.А.Сыроватский, К.А.Татарников «Система предотвращения попадания / вывода самолёта из штопора», доклад на 3-й российско-китайской научной конференции по аэродинамике и динамике полёта самолёта, Центральный Аэрогидродинамический институт (ЦАГИ), г.Жуковский, 1993 г., 14 стр.
M.Goman, A.Khramtsovsky, V.Soukhanov, V.Syrovatsky and K.Tatarnikov "Aircraft Spin Prevention/Recovery Control System", presented at the Third Russian-Chinese Scientific Conference on Aerodynamics and Flight Dynamics of Aircraft, Central Aerohydrodynamic Institute (TsAGI), Zhukovsky, Moscow region, Russia, November 9-12, 1993, 14 pp.
IRJET- Four Propellers Submarine Drone ModellingIRJET Journal
This document summarizes a study on modeling and simulating a four-propeller submarine drone using Matlab. It presents the mathematical modeling of the submarine's kinematics and dynamics. The kinematic model describes the vehicle's motion and orientation using Euler angles. The dynamic model accounts for forces like weight, buoyancy and thrust from the four propellers. The simulation aims to analyze the submarine's behavior under different propeller configurations to validate the multi-thruster propulsion system architecture.
This article considers different approaches for autopilot controller gain values adjustment. The correct autopilot
performance is tested using modeling methods. A variant of land-based autopilot is considered. Examined are
scenarios of UAV airplanes in level flight. The latter are applicable to tasks such as remote sensing, controlled
area surveillance, etc.
- Guided missiles use autopilots and control surfaces like elevators and rudders to adjust their trajectory in flight. Autopilots help control the missile's roll, pitch, and yaw motions.
- Aerodynamic derivatives describe the missile's response to control surface deflections, and are used to develop transfer functions for the roll, pitch, and yaw autopilots.
- Lateral and roll autopilots are designed to control motion in the yaw and roll planes respectively. The lateral autopilot relates lateral acceleration and yaw rate to rudder deflection using aerodynamic derivatives. The roll autopilot minimizes cross-coupling between controls.
IRJET- Design and Optimization of Sailplane for Static and Dynamic StabilityIRJET Journal
This document discusses the design and optimization of a sailplane for static and dynamic stability using open source software. The authors iteratively designed the plane to have stable flight characteristics. Their analysis showed the plane has static stability with its center of gravity 31mm forward of the neutral point. It also has dynamic stability, returning to its original position within 0.2 seconds for short periods, 6 seconds for Dutch rolls, and 400 seconds for phugoid oscillations. The designed sailplane demonstrates good static and dynamic stability.
Functional Simulation of the Integrated Onboard System For a Commercial Launc...irjes
This document summarizes a study on simulating the integrated onboard guidance system of a commercial launch vehicle using GPS technologies. It describes the conceptual design of such a system for a light launch vehicle intended to inject small satellites into low Earth orbit. The key aspects covered include:
1) Choosing between uncoupled, loosely coupled, and tightly coupled integration schemes between the inertial navigation system and GPS receiver.
2) Developing mathematical models of the vehicle's motion, inertial navigation sensors, GPS navigation field, and GPS receiver.
3) Ensuring maximum accuracy in determining the position and velocity of the launch vehicle's 3rd stage at the point of payload separation, in order to meet the accuracy requirements for inject
Hybrid Control Approach to Multi-AUV System in a Surveillance Mission ITIIIndustries
Surveillance missions for multiple autonomous underwater vehicle (AUV) system suggest the use of different modes of operation including organizing and keeping a predefined formation, avoiding obstacles, reaching static and tracking dynamic targets. While exploiting a leader-follower strategy to formation control and the vector Lyapunov function method to controller design, we use discrete-event approach and supervisory control theory to switch between operational modes.
Geometric 3D Path-Following Control for a Fixed-Wing UAV on SO(3)venanziocichella
This document presents a new geometric 3D path-following control algorithm for fixed-wing unmanned aerial vehicles (UAVs). The algorithm uses the Special Orthogonal group SO(3) to formulate the attitude control problem, avoiding singularities. Flight test results demonstrate the efficacy of the path-following control algorithm. The algorithm leads to a multi-loop control structure where an inner-loop controller stabilizes vehicle dynamics and provides reference tracking, while an outer-loop guidance controller controls the vehicle kinematics for path-following capabilities.
Analysis of the skill of a world-class alpine ski racer by using a 3D CAD systemtheijes
Heavy snow areas account for about 50% of the total land area of Japan. Extension of healthy life expectancy is an important issue for residents of heavy snow areas because most of these areas in Japan are depopulated areas. Skiing is a possible lifelong sport in heavy snow areas because gravity rather than muscular power is mainly utilized in skiing. However, in Japan, the number of skiers has declined to 30% of the peak number. This study was conducted with the aim of recovery of the popularity of skiing, and establishing skiing as lifelong winter sport. World-level success of Japanese alpine ski racers is an important factor for the recovery of the popularity of skiing. In this study, the skill of an alpine ski racer was investigated by using a 3D CAD model of a skier with focus on joint work and energy balance in the turn motion.
10 fighter aircraft avionics - part iiiSolo Hermelin
This document provides a summary of fighter aircraft avionics across different generations of fighter jets. It discusses the avionics systems of third, fourth, 4.5 and fifth generation fighters. Specific avionics components covered include cockpit displays, communication systems, data entry/control, flight control, navigation, sensors and weapons systems. The document also discusses topics related to aircraft performance, flight instruments, propulsion and aerodynamics as they relate to fighter jet avionics.
М.Г.Гоман, А.В.Храмцовский, Е.Н.Колесников «Оценка маневренных характеристик самолета посредством численного определения областей асимптотической устойчивости», Journal of Guidance, Control, and Dynamics, Vol. 31, No. 2 (2008), стр. 329-339.
Маневренные характеристики самолета на установившихся режимах полёта обычно оцениваются на основе установившихся решений уравнений движения самолёта как твёрдого тела. В статье описан систематический метод расчета установившихся режимов полета для класса спиральных траекторий.
Mikhail G. Goman, Andrew V. Khramtsovsky, and Evgeny N. Kolesnikov "Evaluation of Aircraft Performance and Maneuverability by Computation of Attainable Equilibrium Sets", Journal of Guidance, Control, and Dynamics, Vol. 31, No. 2 (2008), pp. 329-339.
An aircraft's performance and maneuvering capabilities in steady flight conditions are usually analyzed considering the steady-states of the rigid body equations of motion. A systematic way of computation of the set of all attainable steady states for a general class of helical trajectories is presented. The proposed reconstruction of attainable equilibrium states and their local stability maps provides a comprehensive and consistent representation of the aircraft flight and maneuvering envelopes. The numerical procedure is outlined and computational examples of attainable equilibrium sets in the form of two-dimensional cross-sections of steady-state maneuver parameters are presented for three different aircraft models.
1) The document summarizes current approaches to seismic design and analysis of underground structures like tunnels. It describes how ground deformations from earthquakes are estimated and transmitted to underground structures.
2) Analysis methods include ignoring structure-ground interaction, pseudo-static analysis that imposes ground deformations as static loads, and dynamic analysis using tools like finite element modeling.
3) Recent earthquakes showed underground structures generally suffer less damage than surface structures. However, some underground structures experienced significant damage, like the 1995 collapse of the Daikai subway station in Kobe, Japan, where relative displacement between structure levels exceeded design.
Real Time Implementation of Cartesian Space Control for Underactuated Robot F...idescitation
This paper presents a real time implementation of a sliding mode controller
(SMC) for the underactuated BERUL1 fingers. The use of SMC is to deal with the
inaccuracies and unmodelled nonlinearities in the dynamic model of the robotic fingers, in
particular, to overcome significant friction and stiction. This paper in particular shows a
practical implementation of Cartesian space control for the BERUL fingers. For the
purpose of comparison, the performance of the PID controller is included in this paper.
The main controller for positioning control is the combination of a feedback linearization
(FL) scheme and SMC. The results show that the SMC performed better than the PID
controller in the Cartesian space control.
- Prepared a 2D stick model of the bridge in SAP2000 using the properties mentioned in the FHWA Bridge document
- Designed the bridge for linear and non-linear structural models to conduct analyses
- Performed different analyses on the bridge – multimode analysis, pushover analysis, time history analysis and capacity spectrum analysis
- Compared the shear force, bending moment, axial force and displacement values for each abutment and pier from all analyses and critically assessed the bridge performance
This document describes different coordinate systems and phases of motion used in launch analysis of offshore structures. It summarizes the Launch/Barge coordinate system, Rocker Arm coordinate system, and five phases of motion (Phase 1-5) that describe the structure's motion on the barge during launch. It also provides an overview of the launch analysis capabilities and parameters that can be specified in the analysis.
1
EECS 4200/5200 Term Project (10%) sp21
Modeling of Soft Landing of Mars ‘Perseverance’ Rover
Introduction
On February 18, 2021 the Mars Perseverance Rover landed on Mars’s Jezero Crater. Sent to look
for signs of ancient life and to collect rock samples, the process of landing on Mars safely required
a team of scientists and researchers to derive a series of complex maneuvers. Over the course of
this project, you will take on the role of these scientists and create models of the soft landing
procedure.
Objectives of the Term Project
The term project's primary objective is to impart practical skills necessary to develop a real-world
system model. The student is expected to be able to do the following by the completion of this
term project:
1. To generate a model of a practical system by the laws of the physical sciences governing
the system’s behavior. In this case, it is Translational Motion Mechanical System.
2. Convert the model into a Free Body Diagram with all acting forces presented.
3. Create a Set of Differential Equations pertaining to the diagram.
4. Presentation of the equation in Matrix form with State variables and Output.
5. Develop Signal Flow Graph and defining the System Transfer function.
6. Identification of key design parameters from literatures and reference material and
utilization/application to the modeling process.
7. Calculation of key parameters such as masses, velocities, gravity, etc. Any defined
values from correlating literature (web, text, papers) must be specified regarding author(s),
title, page, date, address (if Web).
2
Background
While performing the soft-landing on Mars, the Perseverance rover underwent a series of stages
where numerous elements of the system would provide support ensuring a safe landing. As far as
the soft-landing is concerned, at approximately 12 kilometers from the surface of Mars, the
parachute of the Perseverance rover was deployed to slow its descent. After a reasonable amount
of deacceleration, the heat shield was removed, allowing the cameras onboard the rover to obtain
their first glimpse of the surface of Mars. Further into the descent, the engine of the hover unit was
activated as the backshell containing the connection to the parachute was separated. At this stage
of the descent, the rover’s landing was assisted by the hover unit providing upward thrust to
decrease the velocity at which it fell. Finally, after a predetermined height over the surface was
reached, the hover unit took on the role of a helicopter and hovered in position. Then, the hover
unit behaved like a “skycrane” where it gradually lowered the rover onto the surface.
3
Project Description
The project you are assigned is concerned with the soft landing of the Perseverance rover; in other
words, starting with the deployment of the parachute and onwards as it descends. For purposes of
t ...
1
EECS 4200/5200 Term Project (10%) sp21
Modeling of Soft Landing of Mars ‘Perseverance’ Rover
Introduction
On February 18, 2021 the Mars Perseverance Rover landed on Mars’s Jezero Crater. Sent to look
for signs of ancient life and to collect rock samples, the process of landing on Mars safely required
a team of scientists and researchers to derive a series of complex maneuvers. Over the course of
this project, you will take on the role of these scientists and create models of the soft landing
procedure.
Objectives of the Term Project
The term project's primary objective is to impart practical skills necessary to develop a real-world
system model. The student is expected to be able to do the following by the completion of this
term project:
1. To generate a model of a practical system by the laws of the physical sciences governing
the system’s behavior. In this case, it is Translational Motion Mechanical System.
2. Convert the model into a Free Body Diagram with all acting forces presented.
3. Create a Set of Differential Equations pertaining to the diagram.
4. Presentation of the equation in Matrix form with State variables and Output.
5. Develop Signal Flow Graph and defining the System Transfer function.
6. Identification of key design parameters from literatures and reference material and
utilization/application to the modeling process.
7. Calculation of key parameters such as masses, velocities, gravity, etc. Any defined
values from correlating literature (web, text, papers) must be specified regarding author(s),
title, page, date, address (if Web).
2
Background
While performing the soft-landing on Mars, the Perseverance rover underwent a series of stages
where numerous elements of the system would provide support ensuring a safe landing. As far as
the soft-landing is concerned, at approximately 12 kilometers from the surface of Mars, the
parachute of the Perseverance rover was deployed to slow its descent. After a reasonable amount
of deacceleration, the heat shield was removed, allowing the cameras onboard the rover to obtain
their first glimpse of the surface of Mars. Further into the descent, the engine of the hover unit was
activated as the backshell containing the connection to the parachute was separated. At this stage
of the descent, the rover’s landing was assisted by the hover unit providing upward thrust to
decrease the velocity at which it fell. Finally, after a predetermined height over the surface was
reached, the hover unit took on the role of a helicopter and hovered in position. Then, the hover
unit behaved like a “skycrane” where it gradually lowered the rover onto the surface.
3
Project Description
The project you are assigned is concerned with the soft landing of the Perseverance rover; in other
words, starting with the deployment of the parachute and onwards as it descends. For purposes of
t ...
This document describes a finite element model developed to simulate the dynamics of an aircraft arresting gear system. The arresting gear is used on aircraft carriers to stop landing aircraft and consists of cables, blocks, dampers, and a hydraulic braking mechanism. The developed model includes all major components of the real system as finite elements. Validation tests showed the model accurately predicts pressures in the hydraulic cylinder and the overall behavior matches experimental data. The validated model is then used to simulate aircraft landings with different masses and velocities to analyze how the arresting gear performs under varying conditions.
Estimation of water momentum and propeller velocity in bow thruster model of...IJECEIAES
Autonomous surface vehicle (ASV) is a vehicle in the form of an unmanned on-water surface vessel that can move automatically. As such, an automatic control system is essentially required. The bow thruster system functions as a propulsion control device in its operations. In this research, the water momentum and propeller velocity were estimated based on the dynamic bow thruster model. The estimation methods used is the Kalman filter (KF) and ensemble Kalman filter (EnKF). There are two scenarios: tunnel thruster condition and open-bladed thruster condition. The estimation results in the tunnel thruster condition showed that the root mean square error (RMSE) by the EnKF method was relatively smaller, that is, 0.7920 and 0.1352, while the estimation results in the open-bladed thruster condition showed that the RMSE by the KF method was relatively smaller, that is, 1.9957 and 2.0609.
LMI based antiswing adaptive controller for uncertain overhead cranes IJECEIAES
This paper proposes an adaptive anti-sway controller for uncertain overhead cranes. The state-space model of the 2D overhead crane with the system parameter uncertainties is shown firstly. Next, the adaptive controller which can adapt with the system uncertainties and input disturbances is established. The proposed controller has ability to move the trolley to the destination in short time and with small oscillation of the load despite the effect of the uncertainties and disturbances. Moreover, the controller has simple structure so it is easy to execute. Also, the stability of the closed-loop system is analytically proven. The proposed algorithm is verified by using Matlab/ Simulink simulation tool. The simulation results show that the presented controller gives better performances (i.e., fast transient response, no ripple, and low swing angle) than the state feedback controller when there exist system parameter variations as well as input disturbances.
Designing and Implementing a Level II HIgh Power Rocket with Dual Electronica...Aaron Blacker
This document outlines the process of designing and implementing a Level II high power rocket with dual electronically triggered parachute deployments. Key aspects include:
1) The rocket utilizes two pressurization chambers to separately deploy an apogee drogue parachute and a lower-altitude main parachute via an onboard electronic circuit.
2) Design considerations include aerodynamic forces, stability based on center of pressure and gravity, structural requirements, and dual-stage recovery system.
3) Dual deployment allows high-altitude deployment of a drogue parachute followed by lower-altitude deployment of a main parachute to descend safely without drifting too far.
All possible questions - KINEMATICS OF MACHINERY / UNIT – ISenthil Kumar
This document contains 50 questions related to the topic of kinematics of machinery from various university exams. The questions cover topics like basic kinematic concepts, degrees of freedom, mobility criteria, inversions of linkages, transmission angles, classifications of mechanisms, common mechanisms, and straight line generators. Example mechanisms discussed include four-bar linkages, slider crank mechanisms, quick return mechanisms, steering mechanisms, and the Peaucellier straight line generator. Formulas related to transmission ratios and torque calculations for mechanisms like Hooke's joint are also included.
M.Goman et al (1993) - Aircraft Spin Prevention / Recovery Control SystemProject KRIT
М.Г.Гоман, А.В.Храмцовский, В.Л.Суханов, В.А.Сыроватский, К.А.Татарников «Система предотвращения попадания / вывода самолёта из штопора», доклад на 3-й российско-китайской научной конференции по аэродинамике и динамике полёта самолёта, Центральный Аэрогидродинамический институт (ЦАГИ), г.Жуковский, 1993 г., 14 стр.
M.Goman, A.Khramtsovsky, V.Soukhanov, V.Syrovatsky and K.Tatarnikov "Aircraft Spin Prevention/Recovery Control System", presented at the Third Russian-Chinese Scientific Conference on Aerodynamics and Flight Dynamics of Aircraft, Central Aerohydrodynamic Institute (TsAGI), Zhukovsky, Moscow region, Russia, November 9-12, 1993, 14 pp.
IRJET- Four Propellers Submarine Drone ModellingIRJET Journal
This document summarizes a study on modeling and simulating a four-propeller submarine drone using Matlab. It presents the mathematical modeling of the submarine's kinematics and dynamics. The kinematic model describes the vehicle's motion and orientation using Euler angles. The dynamic model accounts for forces like weight, buoyancy and thrust from the four propellers. The simulation aims to analyze the submarine's behavior under different propeller configurations to validate the multi-thruster propulsion system architecture.
This article considers different approaches for autopilot controller gain values adjustment. The correct autopilot
performance is tested using modeling methods. A variant of land-based autopilot is considered. Examined are
scenarios of UAV airplanes in level flight. The latter are applicable to tasks such as remote sensing, controlled
area surveillance, etc.
- Guided missiles use autopilots and control surfaces like elevators and rudders to adjust their trajectory in flight. Autopilots help control the missile's roll, pitch, and yaw motions.
- Aerodynamic derivatives describe the missile's response to control surface deflections, and are used to develop transfer functions for the roll, pitch, and yaw autopilots.
- Lateral and roll autopilots are designed to control motion in the yaw and roll planes respectively. The lateral autopilot relates lateral acceleration and yaw rate to rudder deflection using aerodynamic derivatives. The roll autopilot minimizes cross-coupling between controls.
IRJET- Design and Optimization of Sailplane for Static and Dynamic StabilityIRJET Journal
This document discusses the design and optimization of a sailplane for static and dynamic stability using open source software. The authors iteratively designed the plane to have stable flight characteristics. Their analysis showed the plane has static stability with its center of gravity 31mm forward of the neutral point. It also has dynamic stability, returning to its original position within 0.2 seconds for short periods, 6 seconds for Dutch rolls, and 400 seconds for phugoid oscillations. The designed sailplane demonstrates good static and dynamic stability.
Functional Simulation of the Integrated Onboard System For a Commercial Launc...irjes
This document summarizes a study on simulating the integrated onboard guidance system of a commercial launch vehicle using GPS technologies. It describes the conceptual design of such a system for a light launch vehicle intended to inject small satellites into low Earth orbit. The key aspects covered include:
1) Choosing between uncoupled, loosely coupled, and tightly coupled integration schemes between the inertial navigation system and GPS receiver.
2) Developing mathematical models of the vehicle's motion, inertial navigation sensors, GPS navigation field, and GPS receiver.
3) Ensuring maximum accuracy in determining the position and velocity of the launch vehicle's 3rd stage at the point of payload separation, in order to meet the accuracy requirements for inject
Hybrid Control Approach to Multi-AUV System in a Surveillance Mission ITIIIndustries
Surveillance missions for multiple autonomous underwater vehicle (AUV) system suggest the use of different modes of operation including organizing and keeping a predefined formation, avoiding obstacles, reaching static and tracking dynamic targets. While exploiting a leader-follower strategy to formation control and the vector Lyapunov function method to controller design, we use discrete-event approach and supervisory control theory to switch between operational modes.
Geometric 3D Path-Following Control for a Fixed-Wing UAV on SO(3)venanziocichella
This document presents a new geometric 3D path-following control algorithm for fixed-wing unmanned aerial vehicles (UAVs). The algorithm uses the Special Orthogonal group SO(3) to formulate the attitude control problem, avoiding singularities. Flight test results demonstrate the efficacy of the path-following control algorithm. The algorithm leads to a multi-loop control structure where an inner-loop controller stabilizes vehicle dynamics and provides reference tracking, while an outer-loop guidance controller controls the vehicle kinematics for path-following capabilities.
Analysis of the skill of a world-class alpine ski racer by using a 3D CAD systemtheijes
Heavy snow areas account for about 50% of the total land area of Japan. Extension of healthy life expectancy is an important issue for residents of heavy snow areas because most of these areas in Japan are depopulated areas. Skiing is a possible lifelong sport in heavy snow areas because gravity rather than muscular power is mainly utilized in skiing. However, in Japan, the number of skiers has declined to 30% of the peak number. This study was conducted with the aim of recovery of the popularity of skiing, and establishing skiing as lifelong winter sport. World-level success of Japanese alpine ski racers is an important factor for the recovery of the popularity of skiing. In this study, the skill of an alpine ski racer was investigated by using a 3D CAD model of a skier with focus on joint work and energy balance in the turn motion.
10 fighter aircraft avionics - part iiiSolo Hermelin
This document provides a summary of fighter aircraft avionics across different generations of fighter jets. It discusses the avionics systems of third, fourth, 4.5 and fifth generation fighters. Specific avionics components covered include cockpit displays, communication systems, data entry/control, flight control, navigation, sensors and weapons systems. The document also discusses topics related to aircraft performance, flight instruments, propulsion and aerodynamics as they relate to fighter jet avionics.
М.Г.Гоман, А.В.Храмцовский, Е.Н.Колесников «Оценка маневренных характеристик самолета посредством численного определения областей асимптотической устойчивости», Journal of Guidance, Control, and Dynamics, Vol. 31, No. 2 (2008), стр. 329-339.
Маневренные характеристики самолета на установившихся режимах полёта обычно оцениваются на основе установившихся решений уравнений движения самолёта как твёрдого тела. В статье описан систематический метод расчета установившихся режимов полета для класса спиральных траекторий.
Mikhail G. Goman, Andrew V. Khramtsovsky, and Evgeny N. Kolesnikov "Evaluation of Aircraft Performance and Maneuverability by Computation of Attainable Equilibrium Sets", Journal of Guidance, Control, and Dynamics, Vol. 31, No. 2 (2008), pp. 329-339.
An aircraft's performance and maneuvering capabilities in steady flight conditions are usually analyzed considering the steady-states of the rigid body equations of motion. A systematic way of computation of the set of all attainable steady states for a general class of helical trajectories is presented. The proposed reconstruction of attainable equilibrium states and their local stability maps provides a comprehensive and consistent representation of the aircraft flight and maneuvering envelopes. The numerical procedure is outlined and computational examples of attainable equilibrium sets in the form of two-dimensional cross-sections of steady-state maneuver parameters are presented for three different aircraft models.
1) The document summarizes current approaches to seismic design and analysis of underground structures like tunnels. It describes how ground deformations from earthquakes are estimated and transmitted to underground structures.
2) Analysis methods include ignoring structure-ground interaction, pseudo-static analysis that imposes ground deformations as static loads, and dynamic analysis using tools like finite element modeling.
3) Recent earthquakes showed underground structures generally suffer less damage than surface structures. However, some underground structures experienced significant damage, like the 1995 collapse of the Daikai subway station in Kobe, Japan, where relative displacement between structure levels exceeded design.
Real Time Implementation of Cartesian Space Control for Underactuated Robot F...idescitation
This paper presents a real time implementation of a sliding mode controller
(SMC) for the underactuated BERUL1 fingers. The use of SMC is to deal with the
inaccuracies and unmodelled nonlinearities in the dynamic model of the robotic fingers, in
particular, to overcome significant friction and stiction. This paper in particular shows a
practical implementation of Cartesian space control for the BERUL fingers. For the
purpose of comparison, the performance of the PID controller is included in this paper.
The main controller for positioning control is the combination of a feedback linearization
(FL) scheme and SMC. The results show that the SMC performed better than the PID
controller in the Cartesian space control.
- Prepared a 2D stick model of the bridge in SAP2000 using the properties mentioned in the FHWA Bridge document
- Designed the bridge for linear and non-linear structural models to conduct analyses
- Performed different analyses on the bridge – multimode analysis, pushover analysis, time history analysis and capacity spectrum analysis
- Compared the shear force, bending moment, axial force and displacement values for each abutment and pier from all analyses and critically assessed the bridge performance
This document describes different coordinate systems and phases of motion used in launch analysis of offshore structures. It summarizes the Launch/Barge coordinate system, Rocker Arm coordinate system, and five phases of motion (Phase 1-5) that describe the structure's motion on the barge during launch. It also provides an overview of the launch analysis capabilities and parameters that can be specified in the analysis.
1
EECS 4200/5200 Term Project (10%) sp21
Modeling of Soft Landing of Mars ‘Perseverance’ Rover
Introduction
On February 18, 2021 the Mars Perseverance Rover landed on Mars’s Jezero Crater. Sent to look
for signs of ancient life and to collect rock samples, the process of landing on Mars safely required
a team of scientists and researchers to derive a series of complex maneuvers. Over the course of
this project, you will take on the role of these scientists and create models of the soft landing
procedure.
Objectives of the Term Project
The term project's primary objective is to impart practical skills necessary to develop a real-world
system model. The student is expected to be able to do the following by the completion of this
term project:
1. To generate a model of a practical system by the laws of the physical sciences governing
the system’s behavior. In this case, it is Translational Motion Mechanical System.
2. Convert the model into a Free Body Diagram with all acting forces presented.
3. Create a Set of Differential Equations pertaining to the diagram.
4. Presentation of the equation in Matrix form with State variables and Output.
5. Develop Signal Flow Graph and defining the System Transfer function.
6. Identification of key design parameters from literatures and reference material and
utilization/application to the modeling process.
7. Calculation of key parameters such as masses, velocities, gravity, etc. Any defined
values from correlating literature (web, text, papers) must be specified regarding author(s),
title, page, date, address (if Web).
2
Background
While performing the soft-landing on Mars, the Perseverance rover underwent a series of stages
where numerous elements of the system would provide support ensuring a safe landing. As far as
the soft-landing is concerned, at approximately 12 kilometers from the surface of Mars, the
parachute of the Perseverance rover was deployed to slow its descent. After a reasonable amount
of deacceleration, the heat shield was removed, allowing the cameras onboard the rover to obtain
their first glimpse of the surface of Mars. Further into the descent, the engine of the hover unit was
activated as the backshell containing the connection to the parachute was separated. At this stage
of the descent, the rover’s landing was assisted by the hover unit providing upward thrust to
decrease the velocity at which it fell. Finally, after a predetermined height over the surface was
reached, the hover unit took on the role of a helicopter and hovered in position. Then, the hover
unit behaved like a “skycrane” where it gradually lowered the rover onto the surface.
3
Project Description
The project you are assigned is concerned with the soft landing of the Perseverance rover; in other
words, starting with the deployment of the parachute and onwards as it descends. For purposes of
t ...
1
EECS 4200/5200 Term Project (10%) sp21
Modeling of Soft Landing of Mars ‘Perseverance’ Rover
Introduction
On February 18, 2021 the Mars Perseverance Rover landed on Mars’s Jezero Crater. Sent to look
for signs of ancient life and to collect rock samples, the process of landing on Mars safely required
a team of scientists and researchers to derive a series of complex maneuvers. Over the course of
this project, you will take on the role of these scientists and create models of the soft landing
procedure.
Objectives of the Term Project
The term project's primary objective is to impart practical skills necessary to develop a real-world
system model. The student is expected to be able to do the following by the completion of this
term project:
1. To generate a model of a practical system by the laws of the physical sciences governing
the system’s behavior. In this case, it is Translational Motion Mechanical System.
2. Convert the model into a Free Body Diagram with all acting forces presented.
3. Create a Set of Differential Equations pertaining to the diagram.
4. Presentation of the equation in Matrix form with State variables and Output.
5. Develop Signal Flow Graph and defining the System Transfer function.
6. Identification of key design parameters from literatures and reference material and
utilization/application to the modeling process.
7. Calculation of key parameters such as masses, velocities, gravity, etc. Any defined
values from correlating literature (web, text, papers) must be specified regarding author(s),
title, page, date, address (if Web).
2
Background
While performing the soft-landing on Mars, the Perseverance rover underwent a series of stages
where numerous elements of the system would provide support ensuring a safe landing. As far as
the soft-landing is concerned, at approximately 12 kilometers from the surface of Mars, the
parachute of the Perseverance rover was deployed to slow its descent. After a reasonable amount
of deacceleration, the heat shield was removed, allowing the cameras onboard the rover to obtain
their first glimpse of the surface of Mars. Further into the descent, the engine of the hover unit was
activated as the backshell containing the connection to the parachute was separated. At this stage
of the descent, the rover’s landing was assisted by the hover unit providing upward thrust to
decrease the velocity at which it fell. Finally, after a predetermined height over the surface was
reached, the hover unit took on the role of a helicopter and hovered in position. Then, the hover
unit behaved like a “skycrane” where it gradually lowered the rover onto the surface.
3
Project Description
The project you are assigned is concerned with the soft landing of the Perseverance rover; in other
words, starting with the deployment of the parachute and onwards as it descends. For purposes of
t ...
This document describes a finite element model developed to simulate the dynamics of an aircraft arresting gear system. The arresting gear is used on aircraft carriers to stop landing aircraft and consists of cables, blocks, dampers, and a hydraulic braking mechanism. The developed model includes all major components of the real system as finite elements. Validation tests showed the model accurately predicts pressures in the hydraulic cylinder and the overall behavior matches experimental data. The validated model is then used to simulate aircraft landings with different masses and velocities to analyze how the arresting gear performs under varying conditions.
Estimation of water momentum and propeller velocity in bow thruster model of...IJECEIAES
Autonomous surface vehicle (ASV) is a vehicle in the form of an unmanned on-water surface vessel that can move automatically. As such, an automatic control system is essentially required. The bow thruster system functions as a propulsion control device in its operations. In this research, the water momentum and propeller velocity were estimated based on the dynamic bow thruster model. The estimation methods used is the Kalman filter (KF) and ensemble Kalman filter (EnKF). There are two scenarios: tunnel thruster condition and open-bladed thruster condition. The estimation results in the tunnel thruster condition showed that the root mean square error (RMSE) by the EnKF method was relatively smaller, that is, 0.7920 and 0.1352, while the estimation results in the open-bladed thruster condition showed that the RMSE by the KF method was relatively smaller, that is, 1.9957 and 2.0609.
LMI based antiswing adaptive controller for uncertain overhead cranes IJECEIAES
This paper proposes an adaptive anti-sway controller for uncertain overhead cranes. The state-space model of the 2D overhead crane with the system parameter uncertainties is shown firstly. Next, the adaptive controller which can adapt with the system uncertainties and input disturbances is established. The proposed controller has ability to move the trolley to the destination in short time and with small oscillation of the load despite the effect of the uncertainties and disturbances. Moreover, the controller has simple structure so it is easy to execute. Also, the stability of the closed-loop system is analytically proven. The proposed algorithm is verified by using Matlab/ Simulink simulation tool. The simulation results show that the presented controller gives better performances (i.e., fast transient response, no ripple, and low swing angle) than the state feedback controller when there exist system parameter variations as well as input disturbances.
Designing and Implementing a Level II HIgh Power Rocket with Dual Electronica...Aaron Blacker
This document outlines the process of designing and implementing a Level II high power rocket with dual electronically triggered parachute deployments. Key aspects include:
1) The rocket utilizes two pressurization chambers to separately deploy an apogee drogue parachute and a lower-altitude main parachute via an onboard electronic circuit.
2) Design considerations include aerodynamic forces, stability based on center of pressure and gravity, structural requirements, and dual-stage recovery system.
3) Dual deployment allows high-altitude deployment of a drogue parachute followed by lower-altitude deployment of a main parachute to descend safely without drifting too far.
This paper presents a novel six degrees of freedom mechanism to integrate conical article with the cylindrical article which are large and heavy. The six desired motions include six linear motions and six rational motions. The linear motions are vertical, longitudinal and lateral. The vertical motion is achieved by toggle jack, longitudinal by wheel and rail assembly and the lateral motion is achieved by cross slides. The three rotational motions namely pitch, yaw and roll are achieved by simultaneous movement of toggle jacks, simultaneous movement of cross slides and rollers respectively. It is designed in such a way that it sustains the weight of the heavy articles and also prevents slipping and toppling of the conical article. This approach helps to satisfy and fulfil the goal of aligning the main article flange to the conical article flange for further bolting. The mechanism is designed keeping in mind factors like ergonomics and aesthetics.
Determination of Flutter Angle by Resolving Effective Gyroscope Couple to Ret...IRJET Journal
The document discusses determining flutter angles for an airplane by resolving effective gyroscope couples. It presents a control algorithm that uses gyroscope measurements as inputs to predict flutter angles based on conditional statements. A Rayleigh-Ritz beam model and finite element model are developed to model the wing and wingtip fin. Flight tests show the robot can hover using feedback from either motion capture or gyroscope measurements of angular velocity, though position errors are larger when using full attitude estimates from the gyroscope due to drift in the pitch axis estimate.
This document summarizes a computational analysis of flow behavior over a multi-stage launch vehicle with strap-on boosters. A structured grid and commercial CFD software Fluent were used to model the 2D flow field. Finer meshes were generated near vehicle surfaces to capture shocks accurately. Both Euler and Navier-Stokes solvers were tested using various turbulence models. Results aimed to understand complex flow interactions over the multi-component vehicle configuration.
Hexacopter using MATLAB Simulink and MPU SensingIRJET Journal
This document describes the modeling and control of a hexacopter unmanned aerial vehicle using MATLAB simulation. It presents the mathematical modeling of the hexacopter dynamics using Newton-Euler angles and reference frames. PID controllers are developed for altitude, roll, pitch and yaw control. The rotor speeds required for thrust and attitude control are calculated from the PID outputs. Simulation parameters are provided and the results obtained from implementing the PID controllers on the hexacopter model in MATLAB are presented.
An improved swarm intelligence algorithms-based nonlinear fractional order-PI...TELKOMNIKA JOURNAL
This paper presents a nonlinear fractional order proportional integral derivative (NL-FOPID) for autonomous underwater vehicle (AUV) to solve the path tracking problem under the unknown disturbances (model uncertainty or external disturbances). The considered controller schemes are tuned by two improved swarm intelligence optimization algorithms, the first on is the hybrid grey wolf optimization with simulated annealing (HGWO-SA) algorithm and an improved whale optimization algorithm (IWOA). The developed algorithms are assessed using a set of benchmark function (unimodal, multimodal, and fixed dimension multimodal functions) to guarantee the effectiveness of both proposed swarm algorithms. The HGWO-SA algorithm is used as a tuning method for the AUV system controlled by NL-FOPID scheme, and the IWOA is used as a tuning algorithm to obtain the PID controller’s parameters. The evaluation results show that the HGWO-SA algorithm improved the minimal point of the tested benchmark functions by 1-200 order, while the IWOA improved the minimum point by (1-50) order. Finally, the obtained simulation results from the system operated with NL-FOPID shows the competence in terms of the path tracking by 1-15% as compared to the PID method.
This document presents a mathematical model and control schemes for a hexacopter unmanned aerial vehicle. It first develops the nonlinear dynamic model of the hexacopter using Newton-Euler equations, including rotor dynamics. It then proposes two control schemes - PID and backstepping controllers - to control the hexacopter's attitude and altitude. Simulation experiments in Simulink are used to evaluate and compare the performance and stability of the two control techniques under possible disturbances.
Control Synthesis for Marine Vessels in Case of Limited DisturbancesTELKOMNIKA JOURNAL
In view of rapid development of computer technology digital systems of automatic control are
installed on the modern marine vessels for performance of various manoeuvres at optimal trajectories
taking into account features of the ship and active disturbances. In this connection, great number of
problems that deal with construction of automatic control systems, such as minimizing the fulfillment time
of the maneuver, searching for the optimal trajectory, the suppression of various types of exogenous
disturbances like wind and rough sea, arises. In the work, the problem of suppression of exogenous
disturbances acting on a marine vessel, about which we have no information except its boundedness, is
considered. The problem of searching of the controller as a static state feedback is the basis of offered
approach. The system MATLAB-Simulink is accepted as the basic tool of the computer support. An
example of modeling control system for the carrier is presented.
Abstract This paper presents the design and implementation of a quadcopter capable of payload delivery. A quadcopter is a unique unmanned aerial vehicle which has the capability of vertical take-off and landing. In this design, the quadcopter was controlled wirelessly from a ground control station using radio frequency. It was modeled mathematically considering its attitude and altitude, and a simulation carried out in MATLAB by designing a proportional Integral Derivative (PID) controller was applied to a mathematical model. The PID controller parameters were then applied to the real system. Finally, the output of the simulation and the prototype were compared both in the presence and absence of disturbances. The results showed that the quadcopter was stable and able to compensate for the external disturbances.
Abstract This paper presents the design and implementation of a quadcopter capable of payload delivery. A quadcopter is a unique unmanned aerial vehicle which has the capability of vertical take-off and landing. In this design, the quadcopter was controlled wirelessly from a ground control station using radio frequency. It was modeled mathematically considering its attitude and altitude, and a simulation carried out in MATLAB by designing a proportional Integral Derivative (PID) controller was applied to a mathematical model. The PID controller parameters were then applied to the real system. Finally, the output of the simulation and the prototype were compared both in the presence and absence of disturbances. The results showed that the quadcopter was stable and able to compensate for the external disturbances.
Robust Control of a Spherical Mobile RobotIRJET Journal
This document summarizes a research paper about controlling a spherical mobile robot using sliding mode control. It begins with an abstract that describes the challenges of controlling spherical robots due to their underactuated systems. It then provides background on previous control methods for spherical robots. The document presents the kinematic model of a 2-DOF spherical robot and describes how sliding mode control can be used to provide robust control and path following for the robot. It provides the equations for the sliding mode controller design. Finally, it presents simulation results showing the robot following a desired trajectory with minimal tracking error using the sliding mode controller.
This document analyzes the aerodynamic stability and trajectory simulation of a student sounding rocket called the SMART rocket. It develops methods to evaluate the rocket's stability when disturbed during flight and models potential perturbations from thrust errors, airframe imperfections, and wind. An iterative design process improves the rocket's stability margins. Flight trajectory is studied using simulation software under various launch conditions and with/without disturbances. The results provide critical design insights and define allowable launch parameters to fulfill mission requirements of safe recovery and achieving minimum altitude and speed.
This document describes a numerical simulation of the dynamics of a tethered buoy system. It proposes a novel mixed finite element formulation to model the elastic cable in a robust way, even when the Young's modulus is very large. It also uses quaternion variables to describe the floating body's dynamics, providing numerical stability during large rotations. The coupled nonlinear equations governing the cable and body are discretized in time using the implicit Backward Euler method and linearized with a damped Newton's method. Validation simulations are presented to demonstrate the accuracy and robustness of the overall numerical procedure.
Fatigue life estimation of rear fuselage structure of an aircrafteSAT Journals
This document summarizes a study on estimating the fatigue life of the rear fuselage structure of an aircraft. The researchers created a finite element model of the rear fuselage structure in CATIA and analyzed it in MSC.PATRAN and MSC.NASTRAN to identify high stress regions. They found the maximum stress locations were at cut-out corners and rivet holes in the skin. A local model with finer meshing around the cargo door cut-out was also analyzed. Fatigue life was then estimated using Miner's rule and an S-N curve, accounting for factors like surface roughness and reliability. Damage was accumulated over the expected load cycles to predict fatigue life until crack initiation.
Similar to FINITE ELEMENT MODELING AND JACKET LAUCH ANALYSIS USING A BARGE (20)
[OReilly Superstream] Occupy the Space: A grassroots guide to engineering (an...Jason Yip
The typical problem in product engineering is not bad strategy, so much as “no strategy”. This leads to confusion, lack of motivation, and incoherent action. The next time you look for a strategy and find an empty space, instead of waiting for it to be filled, I will show you how to fill it in yourself. If you’re wrong, it forces a correction. If you’re right, it helps create focus. I’ll share how I’ve approached this in the past, both what works and lessons for what didn’t work so well.
Session 1 - Intro to Robotic Process Automation.pdfUiPathCommunity
👉 Check out our full 'Africa Series - Automation Student Developers (EN)' page to register for the full program:
https://bit.ly/Automation_Student_Kickstart
In this session, we shall introduce you to the world of automation, the UiPath Platform, and guide you on how to install and setup UiPath Studio on your Windows PC.
📕 Detailed agenda:
What is RPA? Benefits of RPA?
RPA Applications
The UiPath End-to-End Automation Platform
UiPath Studio CE Installation and Setup
💻 Extra training through UiPath Academy:
Introduction to Automation
UiPath Business Automation Platform
Explore automation development with UiPath Studio
👉 Register here for our upcoming Session 2 on June 20: Introduction to UiPath Studio Fundamentals: https://community.uipath.com/events/details/uipath-lagos-presents-session-2-introduction-to-uipath-studio-fundamentals/
LF Energy Webinar: Carbon Data Specifications: Mechanisms to Improve Data Acc...DanBrown980551
This LF Energy webinar took place June 20, 2024. It featured:
-Alex Thornton, LF Energy
-Hallie Cramer, Google
-Daniel Roesler, UtilityAPI
-Henry Richardson, WattTime
In response to the urgency and scale required to effectively address climate change, open source solutions offer significant potential for driving innovation and progress. Currently, there is a growing demand for standardization and interoperability in energy data and modeling. Open source standards and specifications within the energy sector can also alleviate challenges associated with data fragmentation, transparency, and accessibility. At the same time, it is crucial to consider privacy and security concerns throughout the development of open source platforms.
This webinar will delve into the motivations behind establishing LF Energy’s Carbon Data Specification Consortium. It will provide an overview of the draft specifications and the ongoing progress made by the respective working groups.
Three primary specifications will be discussed:
-Discovery and client registration, emphasizing transparent processes and secure and private access
-Customer data, centering around customer tariffs, bills, energy usage, and full consumption disclosure
-Power systems data, focusing on grid data, inclusive of transmission and distribution networks, generation, intergrid power flows, and market settlement data
What is an RPA CoE? Session 1 – CoE VisionDianaGray10
In the first session, we will review the organization's vision and how this has an impact on the COE Structure.
Topics covered:
• The role of a steering committee
• How do the organization’s priorities determine CoE Structure?
Speaker:
Chris Bolin, Senior Intelligent Automation Architect Anika Systems
What is an RPA CoE? Session 2 – CoE RolesDianaGray10
In this session, we will review the players involved in the CoE and how each role impacts opportunities.
Topics covered:
• What roles are essential?
• What place in the automation journey does each role play?
Speaker:
Chris Bolin, Senior Intelligent Automation Architect Anika Systems
Essentials of Automations: Exploring Attributes & Automation ParametersSafe Software
Building automations in FME Flow can save time, money, and help businesses scale by eliminating data silos and providing data to stakeholders in real-time. One essential component to orchestrating complex automations is the use of attributes & automation parameters (both formerly known as “keys”). In fact, it’s unlikely you’ll ever build an Automation without using these components, but what exactly are they?
Attributes & automation parameters enable the automation author to pass data values from one automation component to the next. During this webinar, our FME Flow Specialists will cover leveraging the three types of these output attributes & parameters in FME Flow: Event, Custom, and Automation. As a bonus, they’ll also be making use of the Split-Merge Block functionality.
You’ll leave this webinar with a better understanding of how to maximize the potential of automations by making use of attributes & automation parameters, with the ultimate goal of setting your enterprise integration workflows up on autopilot.
Must Know Postgres Extension for DBA and Developer during MigrationMydbops
Mydbops Opensource Database Meetup 16
Topic: Must-Know PostgreSQL Extensions for Developers and DBAs During Migration
Speaker: Deepak Mahto, Founder of DataCloudGaze Consulting
Date & Time: 8th June | 10 AM - 1 PM IST
Venue: Bangalore International Centre, Bangalore
Abstract: Discover how PostgreSQL extensions can be your secret weapon! This talk explores how key extensions enhance database capabilities and streamline the migration process for users moving from other relational databases like Oracle.
Key Takeaways:
* Learn about crucial extensions like oracle_fdw, pgtt, and pg_audit that ease migration complexities.
* Gain valuable strategies for implementing these extensions in PostgreSQL to achieve license freedom.
* Discover how these key extensions can empower both developers and DBAs during the migration process.
* Don't miss this chance to gain practical knowledge from an industry expert and stay updated on the latest open-source database trends.
Mydbops Managed Services specializes in taking the pain out of database management while optimizing performance. Since 2015, we have been providing top-notch support and assistance for the top three open-source databases: MySQL, MongoDB, and PostgreSQL.
Our team offers a wide range of services, including assistance, support, consulting, 24/7 operations, and expertise in all relevant technologies. We help organizations improve their database's performance, scalability, efficiency, and availability.
Contact us: info@mydbops.com
Visit: https://www.mydbops.com/
Follow us on LinkedIn: https://in.linkedin.com/company/mydbops
For more details and updates, please follow up the below links.
Meetup Page : https://www.meetup.com/mydbops-databa...
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Blogs: https://www.mydbops.com/blog/
Facebook(Meta): https://www.facebook.com/mydbops/
Discover top-tier mobile app development services, offering innovative solutions for iOS and Android. Enhance your business with custom, user-friendly mobile applications.
ScyllaDB is making a major architecture shift. We’re moving from vNode replication to tablets – fragments of tables that are distributed independently, enabling dynamic data distribution and extreme elasticity. In this keynote, ScyllaDB co-founder and CTO Avi Kivity explains the reason for this shift, provides a look at the implementation and roadmap, and shares how this shift benefits ScyllaDB users.
In our second session, we shall learn all about the main features and fundamentals of UiPath Studio that enable us to use the building blocks for any automation project.
📕 Detailed agenda:
Variables and Datatypes
Workflow Layouts
Arguments
Control Flows and Loops
Conditional Statements
💻 Extra training through UiPath Academy:
Variables, Constants, and Arguments in Studio
Control Flow in Studio
From Natural Language to Structured Solr Queries using LLMsSease
This talk draws on experimentation to enable AI applications with Solr. One important use case is to use AI for better accessibility and discoverability of the data: while User eXperience techniques, lexical search improvements, and data harmonization can take organizations to a good level of accessibility, a structural (or “cognitive” gap) remains between the data user needs and the data producer constraints.
That is where AI – and most importantly, Natural Language Processing and Large Language Model techniques – could make a difference. This natural language, conversational engine could facilitate access and usage of the data leveraging the semantics of any data source.
The objective of the presentation is to propose a technical approach and a way forward to achieve this goal.
The key concept is to enable users to express their search queries in natural language, which the LLM then enriches, interprets, and translates into structured queries based on the Solr index’s metadata.
This approach leverages the LLM’s ability to understand the nuances of natural language and the structure of documents within Apache Solr.
The LLM acts as an intermediary agent, offering a transparent experience to users automatically and potentially uncovering relevant documents that conventional search methods might overlook. The presentation will include the results of this experimental work, lessons learned, best practices, and the scope of future work that should improve the approach and make it production-ready.
AppSec PNW: Android and iOS Application Security with MobSFAjin Abraham
Mobile Security Framework - MobSF is a free and open source automated mobile application security testing environment designed to help security engineers, researchers, developers, and penetration testers to identify security vulnerabilities, malicious behaviours and privacy concerns in mobile applications using static and dynamic analysis. It supports all the popular mobile application binaries and source code formats built for Android and iOS devices. In addition to automated security assessment, it also offers an interactive testing environment to build and execute scenario based test/fuzz cases against the application.
This talk covers:
Using MobSF for static analysis of mobile applications.
Interactive dynamic security assessment of Android and iOS applications.
Solving Mobile app CTF challenges.
Reverse engineering and runtime analysis of Mobile malware.
How to shift left and integrate MobSF/mobsfscan SAST and DAST in your build pipeline.
The Department of Veteran Affairs (VA) invited Taylor Paschal, Knowledge & Information Management Consultant at Enterprise Knowledge, to speak at a Knowledge Management Lunch and Learn hosted on June 12, 2024. All Office of Administration staff were invited to attend and received professional development credit for participating in the voluntary event.
The objectives of the Lunch and Learn presentation were to:
- Review what KM ‘is’ and ‘isn’t’
- Understand the value of KM and the benefits of engaging
- Define and reflect on your “what’s in it for me?”
- Share actionable ways you can participate in Knowledge - - Capture & Transfer
Demystifying Knowledge Management through Storytelling
FINITE ELEMENT MODELING AND JACKET LAUCH ANALYSIS USING A BARGE
1. Tiểu ban Năng lượng, Kỹ thuật công trình, Vận tải và Công nghệ Biển 163
FINITE ELEMENT MODELING AND
JACKET LAUCH ANALYSIS USING A BARGE
Dinh Quang Cuong (1); Ngo Tuan Dung (2)
(1) Institute of Construction for Offshore Engineering (ICOFFSHORE)
University of Civil Engineering - 55 Giai Phong Street - Hanoi
(2) PetroVietnam Marine Shipyard J/S Company (PVshipyard),
No. 65A2, 30/4 Street, Vung Tau; Email: dqc@hn.vnn.vn
Abstract:
There jacket - barge system models can be using Software system, which have
currently on the world and in Vietnam to calculating: StruCAD*3D;
StabCAD; NEPTUNE Developed by Zentech USA; MOSES (Multi
Operational Structural Engineering Simulation) and SACS (Structural
Analysis Computer System), ProgramManual- Engineering Dynamic, Inc.
USA, but their use often by foreigners. The most important problem is the
system simulation includes barge and jacket. This paper presents method
numerically simulate the barge - jacket system for calculating the jacket launch
process using a barge by finite elements software, desire to affirm the ability of our
engineers in the calculation of the problems mentioned above.
PHƯƠNG PHÁP PHẦN TỬ HỮU HẠN GIẢI BÀI TOÁN VẬN CHUYỂN,
ĐÁNH CHÌM KHỐI CHÂN ĐẾ CÔNG TRÌNH BIỂN TỪ SÀ LAN
Tóm tắt:
Có thể dùng các chương trình phần mềm theo phương pháp phần tử hữu hạn
để giải bài toán vận chuyển, đánh chìm khối chân đế từ xà lan. Các chương
trình phần mềm nói trên là: StruCAD*3D; StrabCAD; SASC,… đã được trang
bị tại Việt Nam, tuy nhiên hầu như vẫn chỉ do người nước ngoài sử dụng. Vấn
đề quan trọng nhất khi thực hiện bài toán là sự thống nhất về mặt phương pháp
mô phỏng hệ thống kết cấu khối chân đế và sà lan trong quá trình vận chuyển,
đánh chìm. Báo cáo này trình bầy việc mô phỏng hệ thống kết cấu theo
phương pháp phần tử hữu hạn và một số kết quả ban đầu khi tính toán vận
chuyển, đánh chìm khối chân đế công trình biển bằng thép từ sà lan bằng
chương trình phần mềm theo phương pháp phần tử hữu hạn, với mong muốn
khẳng định khả năng của các kỹ sư của chúng ta có thể giải các bài toán nêu
trên đây.
1. Introduction
The launch process is broadly divided into four dynamically distinct phases:
Phase 1: Jacket sliding over the launch-way of the barge towards the rocker arm
2. Hội nghị Khoa học và Công nghệ Biển toàn quốc lần thứ V164
Phase 2: Jacket sliding on the rocker arm and rotating with respect to the rocker pin
Phase 3: Jacket tipping on one side of the barge
Phase 4: Separation of the jacket from the barge
During each phase, the equations of motion are developed and solved using a powerful
variable time step algorithm [1] [2]. In the launch formulation, the barge-jacket interaction
effect is incorporated and barge and jacket motions (including displacement, velocity, and
acceleration) are computed for each time step, and the reaction forces and hydrodynamic
forces are summarized. Bottom clearance for the jacket can also be checked during the
launch process.
Currently, the program assumes the lateral symmetry of the barge-jacket system, and
thus only Phase 1, Phase 2, and Phase 4 are simulated by the program. Although the first
two phases of jacket motion are constrained to the vertical plane of the barge, the
hydrodynamic forces of the barge and jacket are considered in three dimensions.
2. Simulate the system
2.1. Coordinate Systems: There are five major coordinate systems:
2.1.1.The input coordinate system
The input coordinate system is the coordinate system used to generate barge and jacket
models and to enter launch data. In general, the input coordinate system is also known as
the structural global system when generating the jacket structural model. The x-axis of the
input coordinate system should be parallel to water surface and run along the center of the
barge toward the rocker arm, i.e., the launch direction. It is recommended that the x-axis of
the input coordinate system be chosen along the keel of the launch barge.
2.1.2. The barge body coordinate system
The barge body coordinate systems are fixed in the body with the origin located at the
barge Center of Gravity (C.G.), respectively (Figure 2). The barge body coordinate system
is also used to describe relative motions between jacket and barge during the first two
phases of the launch process.
2.1.3. The jacket body coordinate system
The jacket body coordinate systems are fixed in the body with the origin located at the
jacket Center of Gravity respectively (Figure 2).
2.1.4. The rocker arm coordinate system
The rocker arm coordinate system is fixed in the rocker arm, with its origin at the rocker
pin (Figure 3). The rocker arm coordinate system is mainly used to describe phase 2
motion and jacket-barge interaction forces.
2.1.5. The global (water surface) coordinate system
The global coordinate system, which is an inertial system fixed in space, that the origin
is at the water surface directly above the barge center of gravity before the launch process
begins. The global coordinate system has the same positive directions (X, Y, and Z) as the
3. Tiểu ban Năng lượng, Kỹ thuật công trình, Vận tải và Công nghệ Biển 165
input coordinate system (Figure 1). The barge and jacket motions and hydrodynamic forces
are described in the global coordinate system.
Originally, all the x-axes are in the direction of the barge bow to stern (i.e., in the launch
direction), and all z-axes are vertical upward. The y-axis is determined by the right-hand
rule. By specifying the jacket leading points, trailing points, and trailing edge distance, the
program automatically puts the jacket on the top of the launch runner based the the
assumption that the launch runner is parallel to the barge keel.
2.2. Mathematical Formulation
The forces acting on the jacket-barge system due to inertial, gravitational, frictional, and
hydrostatic and hydrodynamic forces are evaluated, and the equations of motion in the
form
)(tFKXXCXM are established. (1)
M: Total mass matrix of the global coordinate system; C: Damping matrix;
K: Structural stiffness matrix; F(t): Force vector; XXX ;; : Vector of accelerations,
velocities and displacements.
Thus the equations of motion are non-linear and the time domain method of analysis is
inevitable.
4. Hội nghị Khoa học và Công nghệ Biển toàn quốc lần thứ V166
2.3. Model Generation
Other typical input which includes the barge C.G., simulation time and time step, jacket
initial position relative to launch runner, and rocker arm data.
The barge geometry is modeled by 'PANEL' cards. Each panel is a flat area described
by connecting lines of up to 8 points. All the joints in the panel must be in the same plane.
The order of the connecting nodes, whether clockwise or counter-clockwise, will
determine the direction of the panel in accordance with the right hand rule. All the panels
must have inward normal (i.e., the direction of the panel) to form a complete enclosed
body, i.e., the hull of the launch barge.
The jacket model can be generated in any orientation in the input coordinate system
(Figure 4). By defining the contacting surface of the jacket on the barge, the program will
re-orient the jacket. The initial position of the jacket can be determined by further
specifying the initial trailing edge position and the height of rocker pin and rocker arm in
the input coordinate system. Since it is assumed that the barge-jacket system is laterally
symmetric, it is not necessary to specify the relative position in the y-direction.
The contacting surface of the jacket on the barge is defined by specifying four typical
points, i.e., the leading starboard point, the leading port point, the trailing starboard point,
and the trailing port point (Figure 1). These points are used to determine the coordinate
system associated with the contacting surface, and the contacting length of jacket structure
members on the launch runner.
Therefore, the trailing points should be the aft-most points of the jacket structure
members that contact the barge launch runner.
2.4. Initial Equilibrium Position
The barge-jacket system is assumed to be in static equilibrium under the effect of gravity
and hydrostatic forces when the launch simulation begins. The initial equilibrium position
can be obtained by the program based upon mass matrices, geometry, and the relative
5. Tiểu ban Năng lượng, Kỹ thuật công trình, Vận tải và Công nghệ Biển 167
position of the jacket and barge. However, you can also choose to enter the initial draft and
trim of the barge to define the initial equilibrium position. In this case, the program will not
check the unbalanced forces and moments, if any. Therefore, you need to make sure to enter
the correct initial equilibrium position that corresponds with other input data.
2.5. Mass Properties
In addition to structural geometry, the mass properties of the barge and the jacket are
also required for launch analysis. While the mass matrix of the jacket structure is
calculated internally by the program, you must enter the mass matrix of the barge yourself.
2.6. Winch Effect
A system of “winches” may be used to slide the jacket along the launch runner toward
the rocker arm. In this case, it is assumed that a constant winch speed is applied and the
winch process is slow enough that its dynamic effect can be neglected. Winching proceeds
until the jacket sliding velocity is greater than the winch speed. This makes the jacket slide
along the launch runner by its own weight.
2.7. Hydrodynamic Forces and Coefficients
While Morison’s equation is applied to calculate the hydrodynamic forces on the jacket,
the hydrodynamic forces acting on the barge are described by added mass and damping
coefficients. You can choose to enter these hydrodynamic coefficients to override the
default values assigned by the program (Currently not available). Both added mass and
damping coefficients must be entered in a non-dimensional form.
Non-dimensional added mass coefficients are defined as follows:
• For surge, sway, and heave: Aii/ Mass, i = 1, 2, 3
• For roll, pitch, and yaw: Aii/Iii, i = 4, 5, 6
Non-dimensional damping coefficients are defined as follows:
• For surge, sway, and heave: Bii / Mass * (L/g)1/2
i = 1, 2, 3
• For roll, pitch, and yaw: Bii/ Mass * (L/g) 1/2
* (1/L)2
, i = 4, 5, 6
Where lii is mass moment of inertial, L is the length of the barge, and g is the
acceleration due to gravity.
2.8. Load Generation
Each program-generated load case, which corresponds to each time point specified may
include parts or all of the following loads: Buoyancy, hydrodynamic forces, barge-jacket
interaction forces, and inertial forces. Member buoyancy and hydrodynamic forces are
generally transformed to member distributed loads, except that when only avery small
number of the members is submerged, and member concentrated loads are therefore used.
To generate barge-jacket interaction loads, the jacket structure joints lying on the launch
runner that is to receive the launch runner reaction is defined. Based upon these structural
joints, the program will search for the structural members contacting the launch runner,
and subsequently map the interaction forces onto these members. The program assumes
that the rocker arm is relatively rigid with respect to the jacket, and therefore interaction
6. Hội nghị Khoa học và Công nghệ Biển toàn quốc lần thứ V168
forces are distributed uniformly along the structural members contacting the rocker arm
and barge launch runner.
3. Program Output
There are two levels of output. In the Summary Output, Launch Parameters, Initial
Position, Weight and Buoyancy, Phase-wise Motion Summary, and the Height to Water
Surface reports are included. The Detail Report includes the Rigid Body Position Result 6
Degrees of Freedom (DOF), the Velocity of Jacket and Barge (6 DOF), the Acceleration of
Jacket and Barge (6 DOF), the Rocker Arm Forces, and Forces and Moments acting on the
Launch System.
You also have an option to choose output time steps for each phase, which can be
different from the simulation time steps.
To help you better understand the Launch program, sample launch outputs are explained
report-byreport on the following pages.
3.1. Jacket Mass Matrix Report
The Jacket Mass Matrix and Jacket Radius of Gyration are reported in the Input
Coordinate System with the jacket at its original position, i.e., before the jacket is
reoriented and put on the launch way (Figrue 4).
3.2. Launch Parameters and Barge Data Report
The barge-jacket system is assumed to be in static equilibrium under the effect of gravity
and hydrostatic forces when the launch simulation begins. The initial equilibrium position
(with the jacket already on the launch way) is defined by the draft at the barge center of
gravity, and barge trim and heel (Figure 2).
The Barge Radius of Gyration is relative to the body-fixed Barge Coordinate System. The
Rocker Pin location is reported in the Input Coordinate System with the barge launch way
still parallel to the X axis of the Input Coordinate System, i.e., before the barge-jacket
system achieves its initial equilibrium position (Figure 4).
3.3. Weights and Buoyancy and Initial Position Data Report
In the Input Coordinate System, the jacket weight and buoyancy are reported with the
jacket at its original position, i.e., before the jacket is re-oriented and put on the launch way
(Figure 4). However, in the Global Coordinate System, the jacket weight and buoyancy are
reported with the barge-jacket system in its initial equilibrium position (Figure 2).
The initial position data of barge - jacket system are reported in the Global Coordinate
System (Figure 2,4).
7. Tiểu ban Năng lượng, Kỹ thuật công trình, Vận tải và Công nghệ Biển 169
3.4. Rigid Body Position Results
The barge rigid body position (six degrees of freedom) is reported in the Global
Coordinate System, which is fixed in the space with its X-Y plane coinciding with the
water plane. The jacket rigid body position (six degrees of freedom) is reported both in the
Global Coordinate System and in the Barge Coordinate System, which is fixed in the barge
with its origin at the barge C.G.
For Phase 1, the only non-zero relative motion between the jacket and barge is in the
barge Хdirection, since the jacket is sliding on the launch way.
For Phase 2, the jacket has relative skid and rotational motion with respect to the barge.
These relative motion components are described as motion in 'X', 'Z' and 'Pitch' in the
Barge Coordinate System.
For Phase 4, the jacket has been separated from the barge. Thus no relative motion is
reported.
Figure 8: Phase 4 Motion Figure 9: Height to Water Surface and
Bottom Clearance
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3.5. Velocity and Acceleration of Jacket and Barge
The barge velocity is reported in the Global Coordinate System, which is fixed in
space with its X-Y plane coinciding with the water plane.
The jacket velocity is reported in both the Global Coordinate System and in the
Barge Coordinate System, which s fixed in the barge with its origin at the barge C.G.
3.6. Force Table
The total contacting forces between the jacket and barge are reported in the rocker arm
coordinate system, which is fixed in the rocker arm with the local z direction always
perpendicular to the rocker arm top and the x-direction originally in the launch direction
(Figure 3). Note that the rocker arm Y-direction is determined by the right hand rule.
3.7 Forces and Moments acting on the Launch System
All the forces and moments acting on the barge are reported in the coordinate system,
which origin is located at the barge C.G. and the X-Y-Z axes in the same direction as those
of the Global Coordinate System (Figure 5).
All the forces and moments acting on the jacket are reported in the coordinate system,
which origin is located at the jacket C.G. and the X-Y-Z axes in the same direction as those
of the Global Coordinate System (Figure 5).
3.8. Phase 1 Motion Report
In this report, the barge motions are reported in the Global Coordinate System. Since
the only relative motion between the jacket and the barge is in the x-direction of the Barge
Coordinate System (fixed in the barge), the jacket motions are better described as relative
motion. Note that the x-direction of the Barge Coordinate System will be different from
that of the Global Coordinate System if the barge has a non-zero pitch/trim angle.
Only the most important barge motions, i.e., surge, heave, and pitch, are included in this
summary report. The other motion information can be found in the detail report.
3.9. Phase 2 Motion Report
For Phase 2, both the barge and jacket motions are reported in the Global Coordinate
System. The relative skid velocity is reported in the Rocker Arm System (fixed in the
rocker arm). The relative position (X-direction) is still reported in Barge Coordinate
System to be consistent with the Phase 1 relative motion. In addition, the rocker arm
rotating angle and rocker arm contacting force in the rocker arm z-direction are also
reported. The rocker arm force in the rocker arm y-direction can be found in the detail
report. Note that the x-direction of the Rocker Arm Coordinate System will be different
from that of the Global in Barge Coordinate System if rocker arm has a non-zero angle.
Only the most important barge and jacket motions, i.e., surge, heave, and pitch are included in
this summary report. The other motion information can be found in the detail report.
3.10. Phase 4 Motion Report
For Phase 4, both the barge and jacket motions are reported in the Global Coordinate
System. Since the jacket has separated from the barge, no relative motion will be reported.
The bottom clearance is calculated based upon the reference joints you define.
Only the most important barge and jacket motions, i.e., surge, heave, and pitch are included in
9. Tiểu ban Năng lượng, Kỹ thuật công trình, Vận tải và Công nghệ Biển 171
this summary report. The other motion information can be found in thedetail report.
3.11. Height to Water Surface and Bottom Clearance of Jacket
The “Height to Water Surface’ is positive if the joints are above the water surface.
The “Deepest Point” is calculated based upon the reference joints you define.
4. Conclusions
There jacket - barge system models can be using Software system, which have currently
in ICOFFSHORE to calculating: StruCAD*3D; StabCAD; NEPTUNE Developed by
Zentech USA. SACS, Structural Analysis Computer System, Program Manual-
Engineering Dynamic, Inc. USA.
5. Reference
1. Bathe. K. J -Finite Element Procedures in Engineering Analysis-1992.
2. Bathe .K.J - Finite Element Procedures - USA-1996.
3. Peter Bettes - Infinite element - London - 1993
4. Softwares: StruCAD*3D; StrabCAD; NepTune developed by Zentech – USA
5. SACS, Structural Analysis Computer System, Program Manual- Engineering Dynamic,
Inc. USA.