At Ampelmann, our motto is “Offshore access as easy as crossing the street”. We take this very seriously: on a day to day basis hundreds, sometimes thousands of people go to work safely using our systems all across the world. They leave their vessel, wait for the green light and transfer to their workplace, be it an offshore rig, a turbine or an FPSO. We want that experience to be equivalent to crossing the street: be aware of the action you are taking, follow the procedures and complete the transfer easy, safe and fast.
The document discusses autopilot systems and steering gear controls on ships. It provides details on:
- How autopilots work to automatically steer the ship and reduce workload in heavy weather by learning a ship's handling characteristics.
- The different control modes and settings used on autopilot control units, including proportional, integral, derivative controls and weather compensation settings.
- Limitations of autopilot use in rough conditions, tight spaces, slow speeds, or during maneuvers.
- Procedures for changing between manual and autopilot steering, testing equipment, and emergency steering protocols.
An autopilot is a navigational device that automatically steers a ship or aircraft along a steady course. It works by receiving input on the desired course from devices like a GPS and then using actuators to control the rudder to maintain that heading. The main modes of an autopilot are manual, where the user controls steering, auto where the autopilot maintains the current course, and GPS mode where it follows a route from a GPS unit. Understanding how an autopilot works helps ensure safe navigation at sea.
This document discusses autonomous underwater vehicles (AUVs) and their use for ocean surveys. It describes how AUVs are becoming more widely used due to improvements in battery technology, propulsion efficiency, and pressure vessel design. However, there is a perception that AUVs are expensive, complex and risky to operate. The document examines the advantages and disadvantages of using AUVs compared to towed instruments for ocean margin surveys, and illustrates the development of scientific AUV Autosub and how it has overcome technological challenges to achieve greater depth and range through integrated sensors. It also discusses reasons why AUVs have not been more generally adopted for ocean surveys.
This document presents information about underwater robots. It discusses how underwater robots can operate autonomously or be remotely operated. Applications include military, commercial, research, and oceanography uses. It then describes an Indian autonomous underwater vehicle called AUV-150 and its specifications. The document discusses the design of an underwater dredging robot, including its main frame, dredging mechanism, walking mechanism, and heave mechanism. It shows the simulation analysis of water flow impact and surface pressure on the robot. The conclusion states that these robots can be used for cleaning water bodies and can walk with a special movement principle.
This technical note discusses synchronization of tracking antennas for a satellite detection system using sky-scanning techniques. It proposes synchronizing antenna sweeps between transmitter and receiver sites up to 1000 miles apart to within 1 degree. Potential methods include directly connecting sites, synchronizing each to a common time source like WWV, or using precision local time generators synchronized to WWV. Antenna sweep rates of 6, 9, or 12 degrees per second are recommended to simplify synchronization. Synchronization is deemed entirely practical through use of stable local oscillators synchronized to WWV time signals.
This document discusses a biomimetic approach to correcting for underwater currents in autonomous underwater vehicle (AUV) inertial navigation systems. It proposes mounting an array of lateral pressure sensors on an AUV, similar to a fish's lateral line, to detect differences in pressure caused by underwater currents. Computational fluid dynamics simulations showed pressure differences on an AUV's sides correspond to the speed and direction of currents. An experimental function could relate pressure differences to current characteristics. The AUV control system could then use this to correct for drifting caused by currents and maintain the intended trajectory.
This project investigates docking capabilities for autonomous underwater vehicles (AUVs) to address issues with launching and recovering AUVs from ships. The student will model the motion of AUVs, design autopilot controllers, and develop guidance strategies for docking. Motion will be modeled using 6 degree of freedom and 3 degree of freedom models. Linear parameter varying controllers will be designed for heading, depth, and longitudinal velocity. Two docking strategies, three point and N-point, will be developed using path following and evaluated for stationary and non-stationary docking scenarios. The performance of heading controllers under the two strategies will be compared.
The document discusses autopilot systems and steering gear controls on ships. It provides details on:
- How autopilots work to automatically steer the ship and reduce workload in heavy weather by learning a ship's handling characteristics.
- The different control modes and settings used on autopilot control units, including proportional, integral, derivative controls and weather compensation settings.
- Limitations of autopilot use in rough conditions, tight spaces, slow speeds, or during maneuvers.
- Procedures for changing between manual and autopilot steering, testing equipment, and emergency steering protocols.
An autopilot is a navigational device that automatically steers a ship or aircraft along a steady course. It works by receiving input on the desired course from devices like a GPS and then using actuators to control the rudder to maintain that heading. The main modes of an autopilot are manual, where the user controls steering, auto where the autopilot maintains the current course, and GPS mode where it follows a route from a GPS unit. Understanding how an autopilot works helps ensure safe navigation at sea.
This document discusses autonomous underwater vehicles (AUVs) and their use for ocean surveys. It describes how AUVs are becoming more widely used due to improvements in battery technology, propulsion efficiency, and pressure vessel design. However, there is a perception that AUVs are expensive, complex and risky to operate. The document examines the advantages and disadvantages of using AUVs compared to towed instruments for ocean margin surveys, and illustrates the development of scientific AUV Autosub and how it has overcome technological challenges to achieve greater depth and range through integrated sensors. It also discusses reasons why AUVs have not been more generally adopted for ocean surveys.
This document presents information about underwater robots. It discusses how underwater robots can operate autonomously or be remotely operated. Applications include military, commercial, research, and oceanography uses. It then describes an Indian autonomous underwater vehicle called AUV-150 and its specifications. The document discusses the design of an underwater dredging robot, including its main frame, dredging mechanism, walking mechanism, and heave mechanism. It shows the simulation analysis of water flow impact and surface pressure on the robot. The conclusion states that these robots can be used for cleaning water bodies and can walk with a special movement principle.
This technical note discusses synchronization of tracking antennas for a satellite detection system using sky-scanning techniques. It proposes synchronizing antenna sweeps between transmitter and receiver sites up to 1000 miles apart to within 1 degree. Potential methods include directly connecting sites, synchronizing each to a common time source like WWV, or using precision local time generators synchronized to WWV. Antenna sweep rates of 6, 9, or 12 degrees per second are recommended to simplify synchronization. Synchronization is deemed entirely practical through use of stable local oscillators synchronized to WWV time signals.
This document discusses a biomimetic approach to correcting for underwater currents in autonomous underwater vehicle (AUV) inertial navigation systems. It proposes mounting an array of lateral pressure sensors on an AUV, similar to a fish's lateral line, to detect differences in pressure caused by underwater currents. Computational fluid dynamics simulations showed pressure differences on an AUV's sides correspond to the speed and direction of currents. An experimental function could relate pressure differences to current characteristics. The AUV control system could then use this to correct for drifting caused by currents and maintain the intended trajectory.
This project investigates docking capabilities for autonomous underwater vehicles (AUVs) to address issues with launching and recovering AUVs from ships. The student will model the motion of AUVs, design autopilot controllers, and develop guidance strategies for docking. Motion will be modeled using 6 degree of freedom and 3 degree of freedom models. Linear parameter varying controllers will be designed for heading, depth, and longitudinal velocity. Two docking strategies, three point and N-point, will be developed using path following and evaluated for stationary and non-stationary docking scenarios. The performance of heading controllers under the two strategies will be compared.
This document discusses modelling, design, and control of a remotely operated underwater vehicle (ROV) called Kaxan. It presents: (1) the nonlinear 6 degree-of-freedom hydrodynamic model and parameters of Kaxan; (2) the hardware/software architecture of Kaxan; and (3) simulations of a model-free second order sliding mode controller to control Kaxan in the presence of ocean currents and thruster dynamics. The controller aims to address uncertainties in ROV models from added mass and hydrodynamic effects, as well as disturbances from ocean currents, while avoiding high frequency control signals that can damage actuators.
The document discusses factors that affect aircraft takeoff and landing performance at airfields, including:
- Runway length required for takeoff versus available length based on aircraft weight and design
- Impact of obstacles that must be cleared during takeoff
- Effects of high temperature and altitude on airfield performance due to lower air density
- Impact of wet runways, wind conditions, and maximum certified landing weight on performance.
This document provides an overview of dynamic positioning (DP) systems. It describes how DP began in the 1960s with the first DP vessel, the "Eureka", and is now used on over 1,000 vessels and platforms. The key components of a DP system are explained, including position reference systems, control systems, propulsion and thrusters. Common DP operations are also outlined such as diving, pipelay, drilling and tankering. DP allows vessels to maintain position and heading automatically through propeller thrust.
UNMANNED SURFACE VEHICLE (USV) FOR COASTAL SURVEILLANCEIAEME Publication
The purpose of this paper is to design and fabricate an unmanned surface vehicle (USV) for the coastal surveillance for the maritime of India. It aims to monitor territorial waters on a round-the-clock basis and allows the intelligence to take appropriate action to prevent terrorism, illegal smuggling and human trafficking as the continuous use of an aircraft for surveillance is prohibitively expensive along the Indian coastline which is a massive stretch measuring 7,517km.In this paper an Air Cushioned Vehicle (ACV) popularly known as a Hovercraft is chosen for surveillance as it has the ability to traverse any surface compared to other coastguard vessels thereby earning the title of amphibious boats. Its ability to access 75% of littoral allows them to come on shore during emergencies unlike conventional coastguards that have only 5% littoral access and cannot enter shallow water.
This document discusses autonomous underwater vehicles (AUVs), which are robots that can operate underwater without human presence. It describes the key parameters of AUVs, including sensors, navigation, propulsion, power, and communication systems. Some common sensors are sonar, depth sensors, and magnetometers. Most AUVs use propeller-based thrusters powered by electric motors and batteries. Applications of AUVs include commercial, military, and scientific uses such as ocean exploration and anti-submarine warfare.
This document provides information on basic aerodynamic principles including:
- The four main forces acting on an aeroplane in level flight are lift, weight, thrust, and drag. Lift opposes weight and thrust opposes drag to maintain equilibrium.
- Lift depends on factors like airspeed, air density, wing shape, angle of attack. It can be calculated using a formula involving coefficient of lift.
- Thrust directly opposes drag. Power is the rate of doing work and is the product of thrust and true airspeed.
- Drag has two main components - induced drag from wingtip vortices and profile (parasite) drag from friction and interference. Total drag is the sum
This document provides information about dynamic positioning (DP) systems used on vessels. It begins with a summary of DP from Wikipedia, explaining that DP uses propellers and thrusters controlled by a computer system to automatically maintain a vessel's position and heading. It then discusses the history of DP, compares DP to other position keeping methods, lists applications of DP, and describes the requirements and components of DP systems, including position reference systems. The document provides technical details about DP systems for an intermediate professional audience.
APACHE 4 AUTONOMOUS HYDROGRAPHIC SURVEY USV CALL/ WA 082119953499Budi anto
Hubungi Kami : PT. MINDS INDO SURVEY
Komp. Ruko Mega Kalimalang Kav.8 No.11
Jln.KH.Noer Ali Pekayon Jaya Bekasi 17148
Tlp : 02188860786, Fax : 02188860790
Mobile : 082119953499/ 081388802423
Email : budi1080@gmail.com
RUANG LINGKUP KEGIATAN
PENJUALAN, SERVICE / PERBAIKAN DAN PENYEWAAN
ALAT-ALAT UKUR
Penjualan :
• Alat Ukur
- Total Station (baru dan second hand)
- Theodolite (baru dan second hand)
- Levels (baru dan second hand)
- GPS Handheld
- GPS Geodetik
- UAV dan USV
- Compass
- Clinometer
- Tandem
- Altimeter
- Digital Planimeter
- Walking Measure
- Digital Level
- Phantograph
- Laser Tools Spectra
• Accessories :
- Tripod
- Prisma Detail dan Poligon
- Rambu Ukur 3m, 4m, 5m, dan 7m
- Meteran
- Jalon
Layanan Rental :
- Total Station
- Theodolite
- Autolevel
- GPS Geodetik Statik dan RTK
Merek Alat Ukur Yang Tersedia :
- Nikon
- Sokkia
- Topcon
- Leica
- Spectra
- CHC
- Horizon
- Garmin
- Trimble
- Minds dll.
SERVICE / PERBAIKAN DAN KALIBRASI MACAM-MACAM ALAT UKUR
HARGA MENARIK / COMPETITIVE
Catatan : Price List akan dikirim sesuai permintaan
Contact Person
Budianto
0813 8880 2423
0821 1995 3499
This document provides information about autonomous underwater vehicles (AUVs). It discusses that AUVs are robotic devices that are controlled and piloted by onboard computers to perform underwater survey missions. They use various sensors like DVL, CTD, side-scan sonars, and magnetometers to navigate autonomously and map ocean features. AUVs can navigate using acoustic positioning systems when operating within a net of seafloor transponders or using ultra-short baseline positioning relative to a surface ship's GPS position. They are powered primarily by rechargeable batteries and propelled by propeller-based thrusters. AUVs have commercial uses in mapping seafloors for oil/gas infrastructure and military uses like mine
This document proposes a system of low-cost autonomous underwater vehicles (AUVs) that work together in swarms to harvest energy from ocean currents. The swarms are guided by a master swarm and use sensors to monitor the environment. Each AUV contains a turbine to convert the kinetic energy of ocean currents into electricity, as well as sensors and an autonomous intelligence system called ATON to guide the swarm's movements and energy harvesting based on environmental conditions and wave patterns. The goal is to tap into an unlimited source of renewable energy through a low-cost system while maintaining a balanced marine ecosystem.
DP / PM awareness courses have been created in response to the increasing concern by drilling operators and oil majors, that there is a shortage of experience and a diluted competency with regard to Dynamic Positioning, and the specific aspects of drilling.
Gliders the autonomous under water vehiclesNasihaHussain
This document discusses autonomous underwater gliders, which are unmanned submarine vehicles that can profile the ocean over long periods of time in a cost-effective manner. Gliders use changes in buoyancy to move up and down in the water column, and wings to generate forward motion in a sawtooth pattern. They carry sensors to measure oceanographic properties and surface periodically to transmit data via satellite. Key advantages are their ability to gather data over large ocean areas at high frequency and in all weather conditions at a fraction of the cost of traditional ship-based sampling. Common applications include oceanographic profiling, feature tracking, and boundary monitoring.
This presentation discusses anti-rollover technology incorporated in cars. Physics behind a car rollover, companies who have this technology. Also. various tests conducted to test rollover of a vehicle.
Impact of Different Wake Models on the Estimation of Wind Farm Power GenerationWeiyang Tong
For citations, please refer to the journal version of this paper,
by Tong et al., "Sensitivity of Wind Farm Output to Wind Conditions, Land Configuration, and Installed Capacity, Under Different Wake Models", J. Mech. Des. 137(6), 061403 (Jun 01, 2015) (11 pages), Paper No: MD-14-1339; doi: 10.1115/1.4029892
available at:
http://mechanicaldesign.asmedigitalcollection.asme.org/article.aspx?articleid=2173776
The document discusses progress and challenges in foundational hypersonics research. It notes that hypersonic flight requires integration across multiple disciplines including aerodynamics, materials science, and combustion. Recent accomplishments include unprecedented insights from large-scale simulations and optical diagnostics, as well as international partnerships providing opportunities for scientific flight research through programs like HIFiRE. Ongoing challenges include fully understanding nonequilibrium phenomena at small scales and limited access to hypersonic flight environments for testing.
The document provides details of the preliminary design review for the ESAT PicoSatellite project. It summarizes the project scope, including developing a small satellite to stabilize attitude using magnetic control and carry scientific sensors to study the atmosphere. It outlines the work breakdown structure and block diagrams. Significant portions of the document discuss the proposed attitude control system using permanent magnets, calculations of magnetic and drag torques, and experimental plans. It also summarizes the sensor payload, power management system, and communications system designs. Next steps outlined include further refining several subsystem designs through experimentation and construction.
This document provides an overview of autonomous underwater vehicles (AUVs). It defines AUVs as robots that can travel underwater without human input. The document outlines the basic components of AUVs including sensors, navigation systems, propulsion, power/energy sources, communications, and autonomy capabilities. Applications of AUVs are discussed in commercial, military, research, and investigative contexts. Specific AUV manufacturers and an Indian-developed AUV called AUV-150 are also mentioned.
Attitude & orbital control system, TTC & M system, Power system, Communication subsystem, Satellite antenna, Space qualification, Equipment Reliability, redundancy
Accessing any offshore structure can be problematic due to the movement of a vessel compared to the structure. Ampelmann has developed the solution for this challenge. Similar to a flight simulator, the Ampelmann eliminates any relative motion by taking instant measurements of the ship’s motions and then compensates them by using 6 hydraulic cylinders. The result: the top of the Ampelmann remains completely stationary compared to the structure. The offshore gangway can then be extended towards the structure so all personnel can walk across safely, even in high wave conditions.
A highly versatile autonomous underwater vehicleAlwin Wilken
This document describes the development of an autonomous underwater vehicle called Galatea that uses a bio-mimetic undulating fin propulsion system. The design involves four aspects: the hydrodynamic shape of the hull based on an airfoil, the undulating fin propulsion system, a control system to manually and eventually autonomously control the vehicle, and sensors for potential applications. Initial testing of the undulating fin propulsion in a rig provided insights into thrust generation relationships with variables like deflection, frequency, and wave number. Future work will involve further developing and testing the autonomous control system and sensors, as well as conducting particle image velocimetry tests to better understand the fluid dynamics of the undulating fin propulsion.
This document discusses modelling, design, and control of a remotely operated underwater vehicle (ROV) called Kaxan. It presents: (1) the nonlinear 6 degree-of-freedom hydrodynamic model and parameters of Kaxan; (2) the hardware/software architecture of Kaxan; and (3) simulations of a model-free second order sliding mode controller to control Kaxan in the presence of ocean currents and thruster dynamics. The controller aims to address uncertainties in ROV models from added mass and hydrodynamic effects, as well as disturbances from ocean currents, while avoiding high frequency control signals that can damage actuators.
The document discusses factors that affect aircraft takeoff and landing performance at airfields, including:
- Runway length required for takeoff versus available length based on aircraft weight and design
- Impact of obstacles that must be cleared during takeoff
- Effects of high temperature and altitude on airfield performance due to lower air density
- Impact of wet runways, wind conditions, and maximum certified landing weight on performance.
This document provides an overview of dynamic positioning (DP) systems. It describes how DP began in the 1960s with the first DP vessel, the "Eureka", and is now used on over 1,000 vessels and platforms. The key components of a DP system are explained, including position reference systems, control systems, propulsion and thrusters. Common DP operations are also outlined such as diving, pipelay, drilling and tankering. DP allows vessels to maintain position and heading automatically through propeller thrust.
UNMANNED SURFACE VEHICLE (USV) FOR COASTAL SURVEILLANCEIAEME Publication
The purpose of this paper is to design and fabricate an unmanned surface vehicle (USV) for the coastal surveillance for the maritime of India. It aims to monitor territorial waters on a round-the-clock basis and allows the intelligence to take appropriate action to prevent terrorism, illegal smuggling and human trafficking as the continuous use of an aircraft for surveillance is prohibitively expensive along the Indian coastline which is a massive stretch measuring 7,517km.In this paper an Air Cushioned Vehicle (ACV) popularly known as a Hovercraft is chosen for surveillance as it has the ability to traverse any surface compared to other coastguard vessels thereby earning the title of amphibious boats. Its ability to access 75% of littoral allows them to come on shore during emergencies unlike conventional coastguards that have only 5% littoral access and cannot enter shallow water.
This document discusses autonomous underwater vehicles (AUVs), which are robots that can operate underwater without human presence. It describes the key parameters of AUVs, including sensors, navigation, propulsion, power, and communication systems. Some common sensors are sonar, depth sensors, and magnetometers. Most AUVs use propeller-based thrusters powered by electric motors and batteries. Applications of AUVs include commercial, military, and scientific uses such as ocean exploration and anti-submarine warfare.
This document provides information on basic aerodynamic principles including:
- The four main forces acting on an aeroplane in level flight are lift, weight, thrust, and drag. Lift opposes weight and thrust opposes drag to maintain equilibrium.
- Lift depends on factors like airspeed, air density, wing shape, angle of attack. It can be calculated using a formula involving coefficient of lift.
- Thrust directly opposes drag. Power is the rate of doing work and is the product of thrust and true airspeed.
- Drag has two main components - induced drag from wingtip vortices and profile (parasite) drag from friction and interference. Total drag is the sum
This document provides information about dynamic positioning (DP) systems used on vessels. It begins with a summary of DP from Wikipedia, explaining that DP uses propellers and thrusters controlled by a computer system to automatically maintain a vessel's position and heading. It then discusses the history of DP, compares DP to other position keeping methods, lists applications of DP, and describes the requirements and components of DP systems, including position reference systems. The document provides technical details about DP systems for an intermediate professional audience.
APACHE 4 AUTONOMOUS HYDROGRAPHIC SURVEY USV CALL/ WA 082119953499Budi anto
Hubungi Kami : PT. MINDS INDO SURVEY
Komp. Ruko Mega Kalimalang Kav.8 No.11
Jln.KH.Noer Ali Pekayon Jaya Bekasi 17148
Tlp : 02188860786, Fax : 02188860790
Mobile : 082119953499/ 081388802423
Email : budi1080@gmail.com
RUANG LINGKUP KEGIATAN
PENJUALAN, SERVICE / PERBAIKAN DAN PENYEWAAN
ALAT-ALAT UKUR
Penjualan :
• Alat Ukur
- Total Station (baru dan second hand)
- Theodolite (baru dan second hand)
- Levels (baru dan second hand)
- GPS Handheld
- GPS Geodetik
- UAV dan USV
- Compass
- Clinometer
- Tandem
- Altimeter
- Digital Planimeter
- Walking Measure
- Digital Level
- Phantograph
- Laser Tools Spectra
• Accessories :
- Tripod
- Prisma Detail dan Poligon
- Rambu Ukur 3m, 4m, 5m, dan 7m
- Meteran
- Jalon
Layanan Rental :
- Total Station
- Theodolite
- Autolevel
- GPS Geodetik Statik dan RTK
Merek Alat Ukur Yang Tersedia :
- Nikon
- Sokkia
- Topcon
- Leica
- Spectra
- CHC
- Horizon
- Garmin
- Trimble
- Minds dll.
SERVICE / PERBAIKAN DAN KALIBRASI MACAM-MACAM ALAT UKUR
HARGA MENARIK / COMPETITIVE
Catatan : Price List akan dikirim sesuai permintaan
Contact Person
Budianto
0813 8880 2423
0821 1995 3499
This document provides information about autonomous underwater vehicles (AUVs). It discusses that AUVs are robotic devices that are controlled and piloted by onboard computers to perform underwater survey missions. They use various sensors like DVL, CTD, side-scan sonars, and magnetometers to navigate autonomously and map ocean features. AUVs can navigate using acoustic positioning systems when operating within a net of seafloor transponders or using ultra-short baseline positioning relative to a surface ship's GPS position. They are powered primarily by rechargeable batteries and propelled by propeller-based thrusters. AUVs have commercial uses in mapping seafloors for oil/gas infrastructure and military uses like mine
This document proposes a system of low-cost autonomous underwater vehicles (AUVs) that work together in swarms to harvest energy from ocean currents. The swarms are guided by a master swarm and use sensors to monitor the environment. Each AUV contains a turbine to convert the kinetic energy of ocean currents into electricity, as well as sensors and an autonomous intelligence system called ATON to guide the swarm's movements and energy harvesting based on environmental conditions and wave patterns. The goal is to tap into an unlimited source of renewable energy through a low-cost system while maintaining a balanced marine ecosystem.
DP / PM awareness courses have been created in response to the increasing concern by drilling operators and oil majors, that there is a shortage of experience and a diluted competency with regard to Dynamic Positioning, and the specific aspects of drilling.
Gliders the autonomous under water vehiclesNasihaHussain
This document discusses autonomous underwater gliders, which are unmanned submarine vehicles that can profile the ocean over long periods of time in a cost-effective manner. Gliders use changes in buoyancy to move up and down in the water column, and wings to generate forward motion in a sawtooth pattern. They carry sensors to measure oceanographic properties and surface periodically to transmit data via satellite. Key advantages are their ability to gather data over large ocean areas at high frequency and in all weather conditions at a fraction of the cost of traditional ship-based sampling. Common applications include oceanographic profiling, feature tracking, and boundary monitoring.
This presentation discusses anti-rollover technology incorporated in cars. Physics behind a car rollover, companies who have this technology. Also. various tests conducted to test rollover of a vehicle.
Impact of Different Wake Models on the Estimation of Wind Farm Power GenerationWeiyang Tong
For citations, please refer to the journal version of this paper,
by Tong et al., "Sensitivity of Wind Farm Output to Wind Conditions, Land Configuration, and Installed Capacity, Under Different Wake Models", J. Mech. Des. 137(6), 061403 (Jun 01, 2015) (11 pages), Paper No: MD-14-1339; doi: 10.1115/1.4029892
available at:
http://mechanicaldesign.asmedigitalcollection.asme.org/article.aspx?articleid=2173776
The document discusses progress and challenges in foundational hypersonics research. It notes that hypersonic flight requires integration across multiple disciplines including aerodynamics, materials science, and combustion. Recent accomplishments include unprecedented insights from large-scale simulations and optical diagnostics, as well as international partnerships providing opportunities for scientific flight research through programs like HIFiRE. Ongoing challenges include fully understanding nonequilibrium phenomena at small scales and limited access to hypersonic flight environments for testing.
The document provides details of the preliminary design review for the ESAT PicoSatellite project. It summarizes the project scope, including developing a small satellite to stabilize attitude using magnetic control and carry scientific sensors to study the atmosphere. It outlines the work breakdown structure and block diagrams. Significant portions of the document discuss the proposed attitude control system using permanent magnets, calculations of magnetic and drag torques, and experimental plans. It also summarizes the sensor payload, power management system, and communications system designs. Next steps outlined include further refining several subsystem designs through experimentation and construction.
This document provides an overview of autonomous underwater vehicles (AUVs). It defines AUVs as robots that can travel underwater without human input. The document outlines the basic components of AUVs including sensors, navigation systems, propulsion, power/energy sources, communications, and autonomy capabilities. Applications of AUVs are discussed in commercial, military, research, and investigative contexts. Specific AUV manufacturers and an Indian-developed AUV called AUV-150 are also mentioned.
Attitude & orbital control system, TTC & M system, Power system, Communication subsystem, Satellite antenna, Space qualification, Equipment Reliability, redundancy
Accessing any offshore structure can be problematic due to the movement of a vessel compared to the structure. Ampelmann has developed the solution for this challenge. Similar to a flight simulator, the Ampelmann eliminates any relative motion by taking instant measurements of the ship’s motions and then compensates them by using 6 hydraulic cylinders. The result: the top of the Ampelmann remains completely stationary compared to the structure. The offshore gangway can then be extended towards the structure so all personnel can walk across safely, even in high wave conditions.
A highly versatile autonomous underwater vehicleAlwin Wilken
This document describes the development of an autonomous underwater vehicle called Galatea that uses a bio-mimetic undulating fin propulsion system. The design involves four aspects: the hydrodynamic shape of the hull based on an airfoil, the undulating fin propulsion system, a control system to manually and eventually autonomously control the vehicle, and sensors for potential applications. Initial testing of the undulating fin propulsion in a rig provided insights into thrust generation relationships with variables like deflection, frequency, and wave number. Future work will involve further developing and testing the autonomous control system and sensors, as well as conducting particle image velocimetry tests to better understand the fluid dynamics of the undulating fin propulsion.
Electro Magnetic Aircraft Launching SystemPremKumar2000
This refers to Electro-Magnetic Aircraft Launching System, or EMALS, which will accelerate aircraft to flight speeds in very short distances. The aim is to replace the steam catapult currently used on aircraft carriers with a linear electric motor. The entire system should fit within the confines of the existing steam catapult. The advantages of such a system are increased operational availability, lower airframe stress due to programmable acceleration profiles, and reduced maintenance (and hence reduced manning).
Wave Energy Technologies Overtopping 1 - Tom Thorpe.pdfErik Friis-Madsen
The document summarizes the TAPCHAN and Wave Dragon wave energy conversion devices. TAPCHAN consists of a tapered channel, reservoir, and power station. Waves are funneled into the reservoir through the tapered channel and the water is used to power a turbine before returning to the sea. Wave Dragon is a floating overtopping device with a central ramp and reservoir. Waves surge over the ramp and into the reservoir, and the captured water then drains through turbines back to the sea. Both devices aim to efficiently harness wave energy with proven technologies like turbines, though only one small TAPCHAN prototype was successfully tested.
Pelamis wave energy converter seminar reportSukh Raj
seminar report on renewable source of energy called pelamis wave energy converter,a technology that uses the motion of ocean surface waves to create electricity.bright scope in future and emerging very fastly.
This document presents the results of a weather windows analysis conducted at three marine renewable energy sites: Egmond aan Zee windfarm off the Dutch coast, the Atlantic Marine Energy Test Site in Belmullet, Ireland, and M2 in the Irish Sea. The analysis quantified levels of access for installing and operating marine renewables based on significant wave height, peak wave period, wind speed, and tidal current. Met-ocean data from 2008 was analyzed using the NAVITAS Techno-Economic model to assess weather windows for a jack-up vessel, crew transfer catamaran, and workboat based on their access limits in the varying conditions at each site. The results show the annual frequency of conditions, percentage of access
The document describes flying windmills as an alternative to conventional wind turbines. Flying windmills are tethered wind turbines that use helium to float hundreds of feet in the air, where wind speeds are higher and steadier. This allows them to capture more energy than land-based turbines. The rotating turbine produces electricity through a generator. It is then transferred down the tether line to be used or stored in batteries. Flying windmills have advantages over conventional turbines as they can access stronger winds higher up and do not have the same space constraints on the ground. The document discusses the lifting mechanism using helium gas and the Magnus effect to keep the turbine stable and vertical in flight.
This report describes the development of a power conversion system for a floating tidal stream generator called the Evopod. A prototype Evopod will generate 25kW and test the effects of the marine environment. Optima Control Solutions designed power conversion equipment including a regenerative power converter, transformers, cables, and control systems to maximize power generation at different tidal flows and minimize transmission losses. Extensive simulation and dynamometer testing validated the design's performance before sea trials.
magenn Air rotor system which can be a future technology and the best alternative to fossil fuels. this uses wind energy as a prime source for power generation and is like a blimb structure that floats at up to 600ft and can generate high amount of power. This balloon or blimb structure is filled with helium air as its lighter than air,
DESIGN OF MINE SHAFT ELEVATOR design guideSuresh Ramarao
This document discusses the design of a mine shaft elevator. It begins by providing background on the history and types of elevators. It then describes design considerations for mine shaft elevators, including options for shaft design (circular vs. horizontal) and parameters like speed, motor selection, suspension ropes, and guide rails. Calculations are shown for selecting these components for a case study mine shaft elevator with a lifting capacity of 32 tons and a height of 730 meters. Key parameters of the elevator design are presented in a table. The conclusions compare the computer-calculated design values to standard parameters.
IRJET- Transmission of Ac Power from Offshore to Onshore by using Low Frequen...IRJET Journal
This document discusses the transmission of AC power from offshore wind farms to onshore grids using low frequency AC transmission. Some key points:
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Offshore personnel transfer dissertation
1. AMPELMANN
THE NEW OFFSHORE ACCESS SYSTEM
D.J. Cerda Salzmann, MSc
Delft University of Technology – DUWIND
Stevinweg 1, 2628 CN Delft, The Netherlands
Tel.: +31 15 27 85077, E-mail: d.j.cerdasalzmann@tudelft.nl
J. van der Tempel, PhD
Ampelmann Company
Rotterdamseweg 380, 2629 HG Delft, The Netherlands
Tel.: +31 15 27 86828, E-mail: j.vandertempel@ampelmann.nl
SUMMARY
To provide safe ship-based access to offshore wind turbines, the Delft University of
Technology has developed a system named "Ampelmann". This system enables safe
transfer of personnel and goods by providing a motionless transfer deck on a vessel.
This deck is mounted on top of a Stewart platform, a mechanism (often used for flight
simulators) that can provide motions in all six degrees of freedom using six hydraulic
cylinders. The Stewart platform is fixed on the ship deck. To keep the transfer deck
motionless, a sensor continuously measures the motions of the ship deck. The
cylinders of the Stewart platform are controlled in such a way that all ship motions are
counteracted, thereby creating a stable and motionless transfer deck.
The main driver within the design and development of the Ampelmann system was
safety. The Ampelmann safety philosophy led to a fully redundant system design
enabling full motion compensation, and thus safe access, in sea states up to 3 meters.
This design was made into a full-scale prototype with all redundancies thoroughly
tested. Finally, the Ampelmann system was taken offshore to prove its function: to
provide safe access to an offshore wind turbine. The Ampelmann system is the first
system ever to provide a full motion-compensating platform to enable safe offshore
access. The system has been thoroughly tested in offshore conditions and proved to
provide safe access in sea states up to 3 meters. After its successful test results, the
Ampelmann system has become commercially available.
1
INTRODUCTION
Due to the increasing amount of offshore wind farms that have been installed over the last years,
near-shore locations to place new wind farms are getting scarce. As a result, wind farms are
gradually being placed farther offshore, where wind speeds are higher and the available locations
have a larger areal extent allowing for wind farms with a larger number of turbines. However, such
sites are commonly in deeper water and subject to rougher wave conditions than the currently
operational wind farms. When regarding operations and maintenance, this presents a practical
problem: accessibility, which is defined as the percentage of time that a turbine can be accessed.
Whenever an offshore wind turbine requires a corrective maintenance action, the turbine will
remain unavailable for electricity production until it is repaired. Lack of accessibility, most probably
due to rough wind and wave conditions, can cause long downtimes thereby reducing the turbine’s
availability. A decreased availability results in a decrease in power production, which will ultimately
lead to revenue loss.
Over 90% of all maintenance actions only require the transfer of personnel and of parts which can
be carried by man or lifted by a turbine’s permanent internal crane [1] [2]. In the offshore wind
2. industry personnel transfers by helicopters are usually not applied due to safety related arguments,
high costs and the fact that a hoisting platform is required on each turbine. Offshore wind turbines
are therefore generally accessed by vessels. Safe transfers are enabled by intentionally creating
frictional contact between the vessel’s bow and the turbine’s boat landing aiming to have no vessel
translations at the point of contact. The main downside of this access method is that it is limited to
moderate wave conditions. Based on industry comments, a fair estimate of the limiting wave
conditions appears to be a significant wave height Hs of 1.5 meter.
Future wind farms at locations with heavier sea conditions will have a significantly decreased
accessibility when using the current ship-based access method, due to the maximum significant
wave height that limits transfers. To examine the accessibility of typical offshore wind farm sites as
a function of the limiting sea state, two Dutch offshore locations with wave data available from [3]
have been selected: the IJmuiden Munitiestortplaats (YM6) and the K13a platform (K13). The
former is situated approximately 37 km offshore, the latter at a distance of about 100 km from shore.
Scatter diagrams with the yearly distribution of sea states of both locations were used to determine
the year-round accessibility of fictive wind farms at these two sites. The YM6 location is
representative for sea conditions at currently operational wind farm sites: the Offshore Windpark
Egmond aan Zee (OWEZ) and the Prinses Amaliawindpark (previously named Windpark Q7) are
situated nearby thus exposed to similar wave conditions. At this site, current access methods
limited to a significant wave height of 1.5 meter result in an accessibility of 68% as shown in Table 1.
At the location farther offshore, K13, this number reduces to 60% for the same access limit. It is
also shown in Table 1 that when the access-limiting significant wave height can be increased to 2.0
or 2.5 meters, a very large increase in accessibility can be achieved at both sites. An increase from
2.5 meters to 3.0 meters has a relatively smaller effect and one can question whether this justifies
the probable additional costs involved.
Table 1 Year-round accessibility for different limiting sea states at two offshore sites
Location
Year-round accessibility [%]
for different limiting sea states
Distance to
shore
Hs,lim =
1.0 m
Hs,lim =
1.5 m
Hs,lim =
2.0 m
Hs,lim =
2.5 m
Hs,lim =
3.0 m
YM6
37 km
45
68
83
91
95
K13
100 km
36
60
76
87
93
With the anticipated increase in number of offshore wind farms in mind, especially at locations
farther offshore with rougher wave climates, it can be stated that there is a clear industry need to
develop a safe ship-based access system for wind turbine maintenance with a high accessibility,
preferably up to a significant wave height of 2.5m.
2
THE AMPELMANN
To create a safe transfer system, it would be ideal to have on a vessel a transfer platform for
which the vessel motions can be compensated in all six degrees of freedom in order to make it
stand still in comparison to the fixed world, in this case the offshore wind turbine. A gangway
between the transfer platform and the turbine will then enable personnel to walk safely from the
vessel to the offshore structure and vice versa.
Systems that can create motions in all six degrees of freedom exist in the form of flight simulators.
The moving part of these simulators is an assembly of a cockpit and video screens. This assembly
3. is set in motion by a configuration of six hydraulic cylinders known as a hexapod or a Stewart
platform, as shown in Figure 1. Due to the use of six cylinders, these platforms can move in a
controlled manner in all six degrees of freedom. This principle seems to be ideally suited to cancel
all motions when mounted on a ship, after replacing the cockpit and video screens by a transfer
deck. A prerequisite for compensating motions is to have accurate real-time measurements of the
ship motions and a control system to convert the motion sensor data into control signals for the
Stewart platform. Thus by combining the technologies of a Stewart platform and motion sensors
active motion compensation can be achieved in all six degrees of freedom. This concept was
invented during a Wind Energy Conference in Berlin in 2002, and was therefore named
“Ampelmann” after the typical little man with the hat in the former East Berlin traffic lights, “das
Ampelmännchen” (Figure 2) making offshore access as easy as crossing the street. An artist’s
impression of the Ampelmann system is shown in Figure 3.
Figure 1 Flight simulator with
Stewart platform
Figure 2 Das
Ampelmännchen
Figure 3 Artist’s impression of the
Ampelmann system
Prior
stated:
•
•
•
•
to the development of the Ampelmann system, the following system requirements were
3
SCALE MODEL TESTS
Highest safety standards
Ship-based system, applicable on a wide range of vessels
No adaptation to wind turbines necessary
Provide accessibility Hs ≥ 2.5m
It was to be examined whether the different technologies combined in the Ampelmann system, i.e.
the Stewart platform and motion sensor, would allow for a motion control fast and accurate enough
to minimize create a motionless upper deck on a moving vessel in order to enable safe transfers. To
research this, a series of scale model tests were performed using a small sized Stewart platform
(cylinder stroke of 20 cm) in combination with an Octans motion sensor (consisting of three
accelerometers and three fibre-optic gyros) and custom-made software. This proof of concept was
conducted by first placing the system on top of a larger Stewart platform (Figure 4) to test and
enhance its performance by fine-tuning of the controls. Finally, the system was mounted on a 4
meter vessel which was placed in a wave basin to excite the vessel with regular and irregular waves
(Figure 5). These scale model test proved the Ampelmann concept: enabling a motionless transfer
deck on top of a moving vessel.
The dry and wet tests performed with the small scale Ampelmann model gave good insights in the
use of the combined technologies of an Octans motion sensor and a hydraulic Stewart platform for
active motion compensation. In random wave fields, the Ampelmann scale model managed to keep
the upper platform of the small Stewart platform nearly motionless with residual motions less than
1cm. The results of this proof-of-concept phase justified continuing with the next phase: creating a
prototype.
4. A
B
C
D
Mooring Lines
Roll Dampers
Octans
Wave height
Measurement
E Hydraulic Pump
F Stewart Platform
Figure 4 Dry test set-up
4
Figure 5 Wet test set-up in wave basin
SAFETY PHILOSOPHY AND DESIGN CONSEQUENCES
After the scale model tests, the next step was to develop a prototype to prove the Ampelmann
concept in real offshore conditions for the purpose of transferring personnel. This objective
presented three new main challenges:
•
•
•
Make the integral Ampelmann system inherently safe for personnel transfer
Create a system that can counteract the motions of a sea-going vessel in Hs = 2.5m
Prove its full operational use in offshore conditions: easy access
Although Stewart platforms with cylinder strokes exceeding 1m are commonly used as flight
simulators, the application of such a platform in offshore conditions is new. To tackle the first
challenge the following safety philosophy was decided upon:
•
•
Operation must continue after a single component failure
This ride-through-failure must work for at least 30 seconds
A safety based design procedure was developed to create a system that is inherently safe whilst
meeting the other two challenges: full motion compensation in predefined sea states and easy
access. This procedure is shown in Figure 6 and defined four sub-objectives:
•
•
•
•
Verify strength of all structural components
Create a Stewart platform that can compensate ship motions in Hs = 2.5m
Ensure full redundancy of the Ampelmann system (motion control)
Prevent possible failures due to human errors
5. Safety Based
Design
Structural
Strength
Ship Motion
Compensation
Motion
Control
Operational
Procedure
No failure
of structural
components
Full motion
compensation
No failure
of critical
components
No failure
due to
human errors
Lloyd’s Register:
• Design Appraisal
• Fabrication
Survey
• Load Test
• Optimized Stewart
platform design
for full motion
compensation in
Hs = 2.5m
• All main
components
redundant
• Trained operators
• Easy access
• Ampelmann Safety Management
System (ASMS) monitors all system
functions, takes mitigation measures
and warns operator
Figure 6 Safety based design procedure
The Stewart platform design is elaborated in Section 5. The structural strength verification was
done by Lloyd’s Register and is treated in Section 6.
To ensure the full redundancy of the Ampelmann system, a Failure Modes and Effects Analysis
(FMEA) was performed to identify the possible failures on all system components and examine the
effect of each failure. For all effects that can result in malfunctioning of the Stewart platform or any
other hazardous situation, directly or indirectly, a measure was taken to either reduce the
occurrence of failure or reduce the effect. This was done for all components until a system design
emerged where component or computational failures could no longer cause unsafe effects. This
meant that after any failure the Ampelmann system is able to continue its functionalities for at least
30 seconds. As a result of the FMEA it was concluded that all critical components in the system had
to be made redundant; all redundancies were tested to prove the ride-through-failure capacity.
To connect all possible component failures to the operational procedures, several HAZID (Hazard
Identification) meetings were held with all stakeholders in the development of the Ampelmann
prototype. The outcome of these meetings led to the drafting of the ASMS: the Ampelmann Safety
Management System. In this extensive spreadsheet based model, all possible failures were
connected to a warning level. These warnings are only visible to the operator, who can assess
whether the person transferring can finish his operation before the system is returned to its settled
position. Only the occurrence of a double failure is relayed to all of the crew: alarm lights will flash
and sirens will sound. A person transferring has 5 seconds before the system will retract itself from
the structure and can either complete the transfer or step back and hold on tight. During these 5
seconds the operator also has the option to abort the operation manually.
To prevent failures due to human errors all Ampelmann operators will be trained properly.
Transferring personnel will receive a safety induction, but will basically only need to look at a traffic
light mounted on the transfer deck. In case the green light is switched on by the operator, it is safe
to walk over the gangway to access the offshore wind turbine: Offshore access as easy as crossing
the street.
6. 5
STEWART PLATFORM DESIGN
The purpose of the Ampelmann system’s Stewart platform is to provide motions in all six degrees
of freedom large enough to keep the platform’s transfer deck motionless on a moving vessel in
predefined sea states. The design of the Stewart platform architecture should therefore enable
compensation of vessel motions in sea states of Hs=2.5m. In addition, the axial forces in the
hydraulic cylinders caused by the transfer deck and gangway should be kept low in order to have
low power requirements and low costs. Finally, mechanical singularities of the platform should be
avoided. Mechanical singularity in a platform can be defined as the configuration or pose of a
mechanism that causes unpredictable behaviour; this is a situation that can and must be prevented
by examining all possible platform poses.
A design process was developed to determine the Stewart platform’s architecture best apt for the
Ampelmann system. This was done by first determining many possible architecture options, limited
by different boundary conditions: cylinder stroke length and size limits. Furthermore, the ultimate
load cases for the Ampelmann application were to be determined. Then a calculation procedure
was performed for all proposed platform architectures to determine the motion envelope, calculate
the cylinder forces and check for singularities. From vessel motion simulations, it was found that
within the motion envelope the vertical excursions were a determining criterion. After different
design considerations the best platform architecture could be selected. The process for determining
the platform architecture is shown in a flowchart in Figure 7. This process yielded the final Stewart
platform architecture as well as a clear procedure for determining future Stewart platform
architectures for Ampelmann systems in case design requirements are altered.
Size Limits
Stroke length
Calculation Procedure
Load cases
Other
Architecture
Parameters
Design Considerations
Preferred Architecture
Figure 7 Flowchart to determine Stewart platform architecture
Subsequently, the motion compensation capacity of the selected Stewart platform architecture
was examined for three different vessel types. For this, vessel motions in all six degrees of freedom
were simulated for these vessels in different sea states. The results are presented in Figure 8,
showing that the objective of enabling motion compensation in a sea state of Hs=2.5m is reached
when the Ampelmann is mounted on a 50m vessel.
Type vessel:
Dimensions:
Displacement:
Max. sea state:
Workability:
Anchor handling tug
24m x 10m x 2.75m
120 tons
Hs = 2.0m
85% (S. North Sea)
Type vessel:
Dimensions:
Displacement:
Max. sea state:
Workability:
Multi purpose vessel
50m x 12m x 3.80m
900 tons
Hs = 2.5m
93% (S. North Sea)
Type vessel:
Dimensions:
Displacement:
Max. sea state:
Workability:
Offshore support vessel
70m x 16m x 5.60m
4000 tons
Hs = 3.0m
97% (S. North Sea)
Figure 8 Motion compensating capacity of the Ampelmann system on different vessels
7. 6
TESTING AND CERTIFICATION
After the assembly of the Ampelmann prototype, a series of tests was performed to ensure the
proper functioning of the Ampelmann system:
•
•
•
•
•
Motion Tests
Redundancy Tests
Motion Compensation Tests
Operation and Emergency Simulation
Operational tests
During the motion tests, first the Stewart platform’s entire motion envelope was verified (Figure 9).
Subsequently the control system was fine-tuned until high motion control accuracies were achieved.
The next step was to verify the full system redundancy. This was done by simulating failures for
each component, checking if its redundant component takes over its functionality and confirming
the proper warning by the Ampelmann Safety Management System.
Figure 9 Motion test
Figure 10 Motion compensation test
After the motion and redundancy tests, the Ampelmann system was loaded on a barge to perform
motion compensation tests outside the Port of Rotterdam (Figure 10). In a sea state of Hs = 1.5 m
the residual motions measured on the transfer deck were less than 4 cm heave and less than 0.5
degrees roll and pitch, confirming the appropriate functioning of the Ampelmann system.
Back onshore, the gangway was mounted onto the transfer deck and operational procedures as
well as emergency cases were simulated as shown in Figure 11. As a final test, the Ampelmann
was installed on the SMIT Bronco to test offshore access in the OWEZ wind farm off the Dutch
coast. The demonstration of a transfer is shown in Figure 12.
Figure 11 Operation Simulation
Figure 12 First operational test
8. In addition to the extensive test sequence, the structural strength of the Ampelmann system was
to be certified. For this Lloyd’s Register performed fabrication surveys on all structural components
during the production phase. Furthermore a design appraisal on the entire design was conducted.
Finally a load test was done by applying 450 kg on the tip of the fully extended gangway, which was
witnessed by Lloyd’s Register.
7
EVALUATION AND OUTLOOK
The development of the Ampelmann idea into a fully functional prototype presented many
challenges. The most prominent challenges were first to prove the concept of active motion
compensation in all six degrees of freedom and subsequently to build a prototype to provide safe
access to offshore wind turbines. The prototype was developed while keeping a strong emphasis on
the inherent safety of the system, which resulted in a proven fully redundant transfer system.
After the transfer demonstration at OWEZ, the Ampelmann became commercially available and
has been applied in different offshore projects. Amongst these projects are the decommissioning of
an offshore platform (Figure 13), where motion compensation was achieved in sea states up to
HS=2.8m, and the installation of transition pieces of offshore wind turbines (Figure 14). During the
different projects, the Ampelmann has made approximately 350 landings and provided over 1600
personnel transfers. A second Ampelmann system has been operational since this summer.
Figure 13 Ampelmann at platform
decommissioning
Figure 14 Ampelmann at transition piece
installation
The next step for the Ampelmann is to significantly increase the accessibility of offshore wind
turbines in order to increase uptime, power production and revenues. The Ampelmann technology
has proven to be a safe method to transfer personnel to offshore wind turbines and can in fact
provide access in sea states up to 3 metres, making offshore access as easy as crossing the street.
REFERENCES
1
2
3
Rademakers, L, and H. Braam. O&M Aspects of the 500 MW Offshore Wind Farm at NL7 –
Optimization Study. DOWEC 10090 rev 1. 2003.
Rademakers, L, and H. Braam. O&M Aspects of the 500 MW Offshore Wind Farm at NL7 –
Baseline Configuration. DOWEC 10080 rev 2. 2002.
www.golfklimaat.nl, January 2009.