This document outlines the lectures for a course on vibrations and dynamics at Imperial College of Science, Technology & Medicine. There will be 10 lectures covering vibration analysis and 6 lectures on dynamics. Topics will include 1-degree of freedom and n-degree of freedom systems, modeling techniques like finite element analysis, and measuring and analyzing vibrations in the time and frequency domains. Understanding vibrations is important for engineering to prevent issues like noise, discomfort, malfunctions, and structural failures.
Shock Simulation of the Optics Mirror Assembly By Numerical MethodIJERA Editor
Satellite faces many extreme types of loading throughout their life time from the harsh launch environment to
the critical space environment. Launch load mainly dynamic is the main design concern for space structure.
Shocks are the one of the most critical dynamic load occurs in spacecraft. Optics Mirror Assembly (OMA) is
used in the telescope of the satellite. The telescope performance relies on dimensional control & the geometric
positioning of the mirror, pointing accuracy and controlled surface deformation of the mirror; Mirror fixation
device (MFD) is used for controlling all these factors. It should not distort due to launch loads mainly shocks as
well as loads during operation of the telescope. In the present work an attempt has been made to perform
experimental and computational analysis of the shock load on Optics Mirror Assembly.
The FE modal for Shock Analysis purpose has been analysed with a specific Linear Transient Response
Analysis in order to obtain the time history of acceleration in several output points. The analysis has been
conducted over the time interval 0 to 62 ms and frequency band between 10 - 10 KHz. In order to verify the
feasibility and reliability of the numerical (Implicit Finite Element Code, Nastran) analysis, the numerical
results obtained by Nastran have been compared with those obtained experimentally in the form of SRS. The
overall outcome of the simulation method has proven its reliability in simulating Satellite payloads subjected to
shocks.
This presentation gives an introduction to mechanical vibration or Theory of Vibration for BE courses. Presentation is prepared as per the syllabus of VTU.For any suggestions and criticisms please mail to: hareeshang@gmail.com or visit:ww.hareeshang.wikifoundry.com.
Thanks for watching this presentation.
Hareesha N G
This was a solo project I completed for Cal Poly Space Systems that involved the design, construction, and testing of a nitrous oxide pressure vessel. This will be used for testing our hybrid rocket propulsion system for the 2017 IREC competition.
Shock Simulation of the Optics Mirror Assembly By Numerical MethodIJERA Editor
Satellite faces many extreme types of loading throughout their life time from the harsh launch environment to
the critical space environment. Launch load mainly dynamic is the main design concern for space structure.
Shocks are the one of the most critical dynamic load occurs in spacecraft. Optics Mirror Assembly (OMA) is
used in the telescope of the satellite. The telescope performance relies on dimensional control & the geometric
positioning of the mirror, pointing accuracy and controlled surface deformation of the mirror; Mirror fixation
device (MFD) is used for controlling all these factors. It should not distort due to launch loads mainly shocks as
well as loads during operation of the telescope. In the present work an attempt has been made to perform
experimental and computational analysis of the shock load on Optics Mirror Assembly.
The FE modal for Shock Analysis purpose has been analysed with a specific Linear Transient Response
Analysis in order to obtain the time history of acceleration in several output points. The analysis has been
conducted over the time interval 0 to 62 ms and frequency band between 10 - 10 KHz. In order to verify the
feasibility and reliability of the numerical (Implicit Finite Element Code, Nastran) analysis, the numerical
results obtained by Nastran have been compared with those obtained experimentally in the form of SRS. The
overall outcome of the simulation method has proven its reliability in simulating Satellite payloads subjected to
shocks.
This presentation gives an introduction to mechanical vibration or Theory of Vibration for BE courses. Presentation is prepared as per the syllabus of VTU.For any suggestions and criticisms please mail to: hareeshang@gmail.com or visit:ww.hareeshang.wikifoundry.com.
Thanks for watching this presentation.
Hareesha N G
This was a solo project I completed for Cal Poly Space Systems that involved the design, construction, and testing of a nitrous oxide pressure vessel. This will be used for testing our hybrid rocket propulsion system for the 2017 IREC competition.
Capital project EPC service in pressure vessels & heat exchangers.
Turn around EPC service in replacement of pressure vessels & heat exchangers.
Pressure vessels and heat exchangers design & engineering.
Pressure vessels & heat exchangers re-rating.
Stress analysis to pressure vessels and other equipment.
Fitness for Service Assessment (FFS) in level 1, 2, & 3 per API 579-1/ASME FFS-1.
Dear all
I have prepare notes for Mechanical vibration as per mumbai university syllabus.In that i have solved only reference example,and i have given cited for that example (like ss rao and seto).While referring it i felt "seto" is very nice book.
Training course at Intermediary level for occupational health professionals. Learn to assess worker exposure to hazardous substances and manage health risks for exposure. Techniques to manage occupational health risk and reduce exposure.
Lecture notes for engineering students for all collegesvasundharasingh70
Important lecture for engineering students. This will be beneficial for BTech students of all branches and is mainly for mechanical, chemical, electrical, computer science, biotechnology, civil engineering students
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Capital project EPC service in pressure vessels & heat exchangers.
Turn around EPC service in replacement of pressure vessels & heat exchangers.
Pressure vessels and heat exchangers design & engineering.
Pressure vessels & heat exchangers re-rating.
Stress analysis to pressure vessels and other equipment.
Fitness for Service Assessment (FFS) in level 1, 2, & 3 per API 579-1/ASME FFS-1.
Dear all
I have prepare notes for Mechanical vibration as per mumbai university syllabus.In that i have solved only reference example,and i have given cited for that example (like ss rao and seto).While referring it i felt "seto" is very nice book.
Training course at Intermediary level for occupational health professionals. Learn to assess worker exposure to hazardous substances and manage health risks for exposure. Techniques to manage occupational health risk and reduce exposure.
Lecture notes for engineering students for all collegesvasundharasingh70
Important lecture for engineering students. This will be beneficial for BTech students of all branches and is mainly for mechanical, chemical, electrical, computer science, biotechnology, civil engineering students
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Structural Design and Analysis of Offshore Wind Turbines from a System Point...Franco Bontempi
Offshore wind turbines are relatively complex structural and mechanical systems located in
a highly demanding environment. In this study, the fundamental aspects and major issues
related to the design of such structures are inquired. The system approach is proposed to
carry out the design of the structural parts: in accordance with this philosophy, a
decomposition of the system (environment, structure, actions/loads) and of the structural
performance is carried out, in order to organize the qualitative and quantitative assessment
in various sub-problems. These can be faced by sub-models of different complexity both for
the structural behavior and for the load models. Numerical models are developed to assess
the safety performance under aerodynamic and hydrodynamic actions. In the structural
analyses, three types of turbine support structures have been considered and compared: a
monopile, a tripod and a jacket.
Ultrasonicmotorbychandanbehera 121126043528-phpapp01AJMAL OB
It has been known for more than 30 years.
The first ultrasonic motor was introduce by v.v lavrinko in 1965.
An Ultrasonic motor is a type of electric motor formed from the ultrasonic vibration of a component, the stator being placed against another, the rotor depending on the scheme of operation.
Conversion of electric energy into motion by inverse piezoelectric effect
Powerpoint presentation of my public PhD defense, held on September 24, 2012.
Title: Mechanical properties of the tympanic membrane - Measurement and modeling
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Transcript: Selling digital books in 2024: Insights from industry leaders - T...BookNet Canada
The publishing industry has been selling digital audiobooks and ebooks for over a decade and has found its groove. What’s changed? What has stayed the same? Where do we go from here? Join a group of leading sales peers from across the industry for a conversation about the lessons learned since the popularization of digital books, best practices, digital book supply chain management, and more.
Link to video recording: https://bnctechforum.ca/sessions/selling-digital-books-in-2024-insights-from-industry-leaders/
Presented by BookNet Canada on May 28, 2024, with support from the Department of Canadian Heritage.
UiPath Test Automation using UiPath Test Suite series, part 3DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 3. In this session, we will cover desktop automation along with UI automation.
Topics covered:
UI automation Introduction,
UI automation Sample
Desktop automation flow
Pradeep Chinnala, Senior Consultant Automation Developer @WonderBotz and UiPath MVP
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
"Impact of front-end architecture on development cost", Viktor TurskyiFwdays
I have heard many times that architecture is not important for the front-end. Also, many times I have seen how developers implement features on the front-end just following the standard rules for a framework and think that this is enough to successfully launch the project, and then the project fails. How to prevent this and what approach to choose? I have launched dozens of complex projects and during the talk we will analyze which approaches have worked for me and which have not.
Search and Society: Reimagining Information Access for Radical FuturesBhaskar Mitra
The field of Information retrieval (IR) is currently undergoing a transformative shift, at least partly due to the emerging applications of generative AI to information access. In this talk, we will deliberate on the sociotechnical implications of generative AI for information access. We will argue that there is both a critical necessity and an exciting opportunity for the IR community to re-center our research agendas on societal needs while dismantling the artificial separation between the work on fairness, accountability, transparency, and ethics in IR and the rest of IR research. Instead of adopting a reactionary strategy of trying to mitigate potential social harms from emerging technologies, the community should aim to proactively set the research agenda for the kinds of systems we should build inspired by diverse explicitly stated sociotechnical imaginaries. The sociotechnical imaginaries that underpin the design and development of information access technologies needs to be explicitly articulated, and we need to develop theories of change in context of these diverse perspectives. Our guiding future imaginaries must be informed by other academic fields, such as democratic theory and critical theory, and should be co-developed with social science scholars, legal scholars, civil rights and social justice activists, and artists, among others.
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
Let's dive deeper into the world of ODC! Ricardo Alves (OutSystems) will join us to tell all about the new Data Fabric. After that, Sezen de Bruijn (OutSystems) will get into the details on how to best design a sturdy architecture within ODC.
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
Neuro-symbolic is not enough, we need neuro-*semantic*
Test PDF
1. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
2M SOLID MECHANICS
VIBRATION LECTURES
October 2005
Lecture 1 Introduction
Lecture 2 Free motion of undamped SDOF systems
Lecture 3 Free motion of damped SDOF systems
Lecture 3A Lagrange’s Equation of Motion
Lecture 4 Forced motion of SDOF systems
Lecture 5 Vibration Isolation
Lecture 6 Base excitation of SDOF systems
Lecture 7 Introduction to 2-DOF systems
Textbooks
B. H. Tongue 2002. Principles of Vibration, Oxford University Press
D. J. Inman 1994. Engineering vibration, Prentice-Hall International
MI - 2M SM Vibration Lecture 1 1
2. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
OVERVIEW
• Vibration Lectures - 10 lectures
• Dynamics Lectures - 6 lectures
• Further notes and tutorial questions in:
2M SM - Lecture notes on Vibration (Yellow booklet)
See the MED Web for all handouts.
MI - 2M SM Vibration Lecture 1 2
3. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
LECTURE 1 - INTRODUCTION
Objectives:
• To provide a road map for the Vibrations &
Dynamics Course
• To give an overview of vibration problems in
engineering
• To review available solution techniques
MI - 2M SM Vibration Lecture 1 3
4. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
ROAD MAP
SOLID
MECHANICS
STATICS DYNAMICS MATERIALS ……..
RIGID BODY VIBRATION 1-DOF
DYNAMICS ANALYSIS SYSTEMS
STEADY FORCES UNSTEADY FORCES N-DOF
RIGID BODIES FLEXIBLE BODIES SYSTEMS
CONTINUOUS
SYSTEMS
MI - 2M SM Vibration Lecture 1 4
5. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
VIBRATION MODES OF A PLATE
MI - 2M SM Vibration Lecture 1 5
6. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
TIME DOMAIN VS FREQUENCY DOMAIN - I
• For vibration analysis, we General arbitrary motion
need to describe the
motion of each point on a
structure.
• If the motion is arbitrary,
we need to describe the TIME
motion in the time
domain.
• If the motion is harmonic, Harmonic motion
we can reduce this
requirement by working in
the frequency domain.
TIME
Can be expressed as x(t)=Asinωt
MI - 2M SM Vibration Lecture 1 6
7. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
TIME DOMAIN VS FREQUENCY DOMAIN - II
AMPLITUDE
We observe
the motion of a FREQUENCY
given point at a
given
frequency
MI - 2M SM Vibration Lecture 1 7
8. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
EXAMPLE OF FREQUENCY DOMAIN ANALYSIS
Vibration shape at natural frequency Vibration shape at any other
=>Mode shape frequency =>Operating deflection
shape
Natural frequency
MI - 2M SM Vibration Lecture 1 8
9. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
WAYS OF REPRESENTING A STRUCTURE
• SPATIAL DESCRIPTION
• Finite element model
• Mass-spring model
ω=82 Hz
• MODAL DESCRIPTION
• Use natural frequencies and mode shapes
• RESPONSE DESCRIPTION
• Use the actual behaviour of the structure
MI - 2M SM Vibration Lecture 1 9
10. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
VIBRATION MEASUREMENTS
Shaker + “sand” method Shaker + Laser method
MI - 2M SM Vibration Lecture 1 10
11. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
CONSEQUENCES OF VIBRATION
• Noise
• Discomfort
• Malfunction
• Shutdown
• Structural failure
MI - 2M SM Vibration Lecture 1 11
12. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
TOTAL STRUCTURAL FAILURE - I
MI - 2M SM Vibration Lecture 1 12
13. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
TOTAL STRUCTURAL FAILURE - II
Engine casing Turbine disk
MI - 2M SM Vibration Lecture 1 13
14. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
NOISE & TRANSMISSION OF VIBRATION
SHAKER
(FORCE INPUT)
CAR ENGINE
MOUNTS
CHASSIS POINT
(RESPONSE OUTPUT)
MI - 2M SM Vibration Lecture 1 14
15. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
FREQUENCY RESPONSE OF A HELICOPTER
THESE MODES OF VIBRATION MAY BE EXCITED BY
THE FORCES DUE TO ROTATION
MI - 2M SM Vibration Lecture 1 15
16. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
NOISE & VIBRATION TRANSMISSION FROM
HEAVY MACHINERY
MI - 2M SM Vibration Lecture 1 16
17. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
RAIL CORRUGATION
MI - 2M SM Vibration Lecture 1 17
18. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
BRIDGE FLUTTER
The unsteady
aerodynamic
forces caused by
the wind excited a
torsional mode of
the bridge,
causing total
structural failure.
MI - 2M SM Vibration Lecture 1 18
19. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
GAS TURBINE BLADE VIBRATION
MI - 2M SM Vibration Lecture 1 19
20. IMPERIAL COLLEGE OF SCIENCE, TECHNOLOGY & MEDICINE
MECHANICAL ENGINEERING DEPARTMENT
WHAT IS THE OBJECTIVE ?
• Find the critical frequencies
• Determine the excitation
• …………………….
• MINIMISE THE RESPONSE
Higher the response, more likely is noise,
malfunction, failure due to high cycle fatigue.
Σ FORCES
RESPONSE = [SYSTEM DESIGN]
∑ DAMPING
• Modify the design
• Change operating conditions
• Increase damping
MI - 2M SM Vibration Lecture 1 20
