Development and Design of ROV Manipulator

The thesis is carried out in collaboration with the student organization UiS Subsea. The primary objective of this thesis is to design and develop a manipulator for the ROV, named YME, using the product development process (PDP). The end goal is to showcase the final product at the MATE ROV Competition 2023. The importance of sustainability has been highlighted in recent years, and this year, MATE ROV Competition focuses on the United Nations Decade of Ocean Science for Sustainable development (2021-2030), and challenge students to contribute to UNs Sustainability goals by seeking sustainable solutions for their projects. The product development process consisted of four phases: planning, concept development, concept generation, and product concept selection. The planning process focused on resource allocation, declaring a mission statement, and establishing a good foundation for the process ahead. Gathering benchmarking information and establishing target specifications was a crucial part of the concept development phase, prior to the concept generation process, as the information and specifications served as a guidance and outline for the concepts to be generated. By a circular economy approach, the reuse of old components within UiS Subsea was evaluated, and potential components were located. The circular economy approach influenced design decisions, and resulted in cost and timeefficiency, and contribution towards sustainability in engineering practices. Concepts were generated for both the manipulator arm and end-effector, and the most promising ones were selected for further development. Eventually one concept for the arm, and one for the end-effector, was selected and further developed through detailed design. Through detailed design, a complete CAD model of the manipulator was made, also material was selected and necessary calculations were performed. The outcome was a three degree of freedom manipulator arm with a rotating end-effector, pitch function, and a telescope function. Through prototyping and extensive testing, the design was evaluated and deemed sufficient according to customer needs and target specifications. The outcome of the project was a fully functional ROV Manipulator able to perform all the required MATE tasks, and contributed greatly towards the successful qualification to the 2023 MATE ROV Competition. However, there was room for further improvement and optimization of both the manipulator and the process, and hopefully the manipulator can serve as a foundation for future UiS Subsea manipulator projects

Bicycle Wheel Test Machine

In recent years, the cycling industry has witnessed huge advancements in bicycle components and materials. The age old goals of speed and low weight are still present today, but the pursuit of these goals may be reducing the structural stability of various components integral to wheel performance, including the wheel hub bearings. These bearings are invaluable to bicycles but little is known about how the forces and loads applied to a bicycle affect the performance of these bearings. Broken axles and hubs are indicators of significant stresses within the hub, but little is known about how the resulting deformation affects the performance of the bearings. Specialized Bicycle Components asked the team to produce a custom test machine to help them study this problem. The team’s goal was to design a machine able to simulate rider and chain loading conditions and measure the corresponding power loss within the hub bearings. Through the implementation of this machine, Specialized hopes to gain vital information about the efficiencies of various hub, axle, and bearing combinations The team consists of three mechanical engineering seniors, Kevin Hom, Dylan Harper, and Ross Williams. Dr. Joseph Mello will be advising the team, and all contact to Specialized will be through the project sponsor Sam Pickman

Development and Design of ROV Manipulator

The thesis is carried out in collaboration with the student organization UiS Subsea. The primary objective of this thesis is to design and develop a manipulator for the ROV, named YME, using the product development process (PDP). The end goal is to showcase the final product at the MATE ROV Competition 2023. The importance of sustainability has been highlighted in recent years, and this year, MATE ROV Competition focuses on the United Nations Decade of Ocean Science for Sustainable development (2021-2030), and challenge students to contribute to UNs Sustainability goals by seeking sustainable solutions for their projects. The product development process consisted of four phases: planning, concept development, concept generation, and product concept selection. The planning process focused on resource allocation, declaring a mission statement, and establishing a good foundation for the process ahead. Gathering benchmarking information and establishing target specifications was a crucial part of the concept development phase, prior to the concept generation process, as the information and specifications served as a guidance and outline for the concepts to be generated. By a circular economy approach, the reuse of old components within UiS Subsea was evaluated, and potential components were located. The circular economy approach influenced design decisions, and resulted in cost and timeefficiency, and contribution towards sustainability in engineering practices. Concepts were generated for both the manipulator arm and end-effector, and the most promising ones were selected for further development. Eventually one concept for the arm, and one for the end-effector, was selected and further developed through detailed design. Through detailed design, a complete CAD model of the manipulator was made, also material was selected and necessary calculations were performed. The outcome was a three degree of freedom manipulator arm with a rotating end-effector, pitch function, xv and a telescope function. Through prototyping and extensive testing, the design was evaluated and deemed sufficient according to customer needs and target specifications. The outcome of the project was a fully functional ROV Manipulator able to perform all the required MATE tasks, and contributed greatly towards the successful qualification to the 2023 MATE ROV Competition. However, there was room for further improvement and optimization of both the manipulator and the process, and hopefully the manipulator can serve as a foundation for future UiS Subsea manipulator projects.The thesis is carried out in collaboration with the student organization UiS Subsea. The primary objective of this thesis is to design and develop a manipulator for the ROV, named YME, using the product development process (PDP). The end goal is to showcase the final product at the MATE ROV Competition 2023. The importance of sustainability has been highlighted in recent years, and this year, MATE ROV Competition focuses on the United Nations Decade of Ocean Science for Sustainable development (2021-2030), and challenge students to contribute to UNs Sustainability goals by seeking sustainable solutions for their projects. The product development process consisted of four phases: planning, concept development, concept generation, and product concept selection. The planning process focused on resource allocation, declaring a mission statement, and establishing a good foundation for the process ahead. Gathering benchmarking information and establishing target specifications was a crucial part of the concept development phase, prior to the concept generation process, as the information and specifications served as a guidance and outline for the concepts to be generated. By a circular economy approach, the reuse of old components within UiS Subsea was evaluated, and potential components were located. The circular economy approach influenced design decisions, and resulted in cost and timeefficiency, and contribution towards sustainability in engineering practices. Concepts were generated for both the manipulator arm and end-effector, and the most promising ones were selected for further development. Eventually one concept for the arm, and one for the end-effector, was selected and further developed through detailed design. Through detailed design, a complete CAD model of the manipulator was made, also material was selected and necessary calculations were performed. The outcome was a three degree of freedom manipulator arm with a rotating end-effector, pitch function, xv and a telescope function. Through prototyping and extensive testing, the design was evaluated and deemed sufficient according to customer needs and target specifications. The outcome of the project was a fully functional ROV Manipulator able to perform all the required MATE tasks, and contributed greatly towards the successful qualification to the 2023 MATE ROV Competition. However, there was room for further improvement and optimization of both the manipulator and the process, and hopefully the manipulator can serve as a foundation for future UiS Subsea manipulator projects

Design Guide for Bearings Used in Cryogenic Turbopumps and Test Rigs

Cryogenic bearings are a unique and specialized area of the overall group of bearings that are used every day in industrial and aerospace applications. Cryogenic bearings operate in a unique environment that is not experienced by most bearing applications. The high speeds of turbomachinery, flow of cryogenic coolants, use of nonstandard materials, and lack of lubrication place unique demands on cryogenic bearings that must be met for the safety and success of the mission. To meet the goals of safety and success, requirements are put on the designer, manufacturer, and user that are not normally applied to off-the-shelf bearings. The designer has to have knowledge of the operating conditions, rotational speeds, loads, stresses, installation methods, inspection criteria, dimensional requirements, and design and analytical tools. The manufacturer needs to be aware of the materials used for cryogenic bearings, special heat treatments required, cleanliness of the processes, and inspection techniques to ensure a good product. The user needs to be aware of the safe handling practices to eliminate corrosion and debris, correct installation and removal procedures, pre- and post-test inspections, and the documentation that follow the bearings. This guide is based on the experiences of engineers at NASA Marshall Space Flight Center (MSFC) that have been involved in bearing research and testing along with specific bearing references that have been written. It is not meant to be a bearing design textbook for cryogenic bearing applications. These are available from many authors. Its purpose is to help the designer, manufacturer, or user in the application of cryogenic bearings to better understand the requirements placed on these bearings

Liquid rocket engine turbopump shafts and couplings

Design criteria and recommended practices are presented for designing tubopump shafts and couplings. Design parameters, material selection, and structural analysis are discussed

Condition Monitoring of Slow Speed Rotating Machinery Using Acoustic Emission Technology

Slow speed rotating machines are the mainstay of several industrial applications worldwide. They can be found in paper and steel mills, rotating biological contractors, wind turbines etc. Operational experience of such machinery has not only revealed the early design problems but has also presented opportunities for further significant improvements in the technology and economics of the machines. Slow speed rotating machinery maintenance, mostly related to bearings, shafts and gearbox problems, represents the cause of extended outages. Rotating machinery components such as gearboxes, shafts and bearings degrade slowly with operating time. Such a slow degradation process can be identified if a robust on-line monitoring and predictive maintenance technology is used to detect impending problems and allow repairs to be scheduled. To keep machines functioning at optimal levels, failure detection of such vital components is important as any mechanical degradation or wear, if is not impeded in time, will often progress to more serious damage affecting the operational performance of the machine. This requires far more costly repairs than simply replacing a part. Over the last few years there have been many developments in the use of Acoustic Emission (AE) technology and its analysis for monitoring the condition of rotating machinery whilst in operation, particularly on slow speed rotating machinery. Unlike conventional technologies such as thermography, oil analysis, strain measurements and vibration, AE has been introduced due to its increased sensitivity in detecting the earliest stages of loss of mechanical integrity. This programme of research involves laboratory tests for monitoring slow speed rotating machinery components (shafts and bearings) using AE technology. To implement this objective, two test rigs have been designed to assess the capability of AE as an effective tool for detection of incipient defects within low speed machine components (e.g. shafts and bearings). The focus of the experimental work will be on the initiation and growth of natural defects. Further, this research work investigates the source characterizations of AE signals associated with such bearings whilst in operation. It is also hoped that at the end of this research program, a reliable on-line monitoring scheme used for slow speed rotating machinery components can be developed

Gearing

Gearing technology in its modern form has a history of only 100 years. However, the earliest form of gearing can probably be traced back to fourth century B.C. Greece. Current gear practice and recent advances in the technology are drawn together. The history of gearing is reviewed briefly in the Introduction. Subsequent sections describe types of gearing and their geometry, processing, and manufacture. Both conventional and more recent methods of determining gear stress and deflections are considered. The subjects of life prediction and lubrication are additions to the literature. New and more complete methods of power loss predictions as well as an optimum design of spur gear meshes are described. Conventional and new types of power transmission systems are presented

Development of a titanium sheet manufacturing process via direct powder rolling and spark plasma sintering.

Masters Degree. University of KwaZulu-Natal, Durban.The intention of this research was the improvement of titanium processing in South African industry. South Africa currently has limited ability to efficiently process its titanium reserves and the results of this research, combined with other work in the associated research consortium, has the potential to lead to significant positive economic impact. A novel method of titanium processing, combining the processes of direct powder rolling (DPR) and spark plasma sintering (SPS), was explored in the course of this research. A rolling mill was designed using modelling and simulation techniques, manufactured based on the resulting design, and the DPR-SPS process parametrically tested on the rolling mill using commercially pure titanium powder. The mechanical aspects of this project included experimental testing on a range of titanium powder samples to determine the properties of the powder, modelling of the rolling mill behaviour using MATLAB, 3D modelling of the proposed and iterated rolling mill frame design and its components using Siemens NX and OnShape, finite element analysis of the rolling mill frame and auxiliary components using Siemens NX, and manufacture and parametric testing of the mill for titanium powder compaction. The electrical aspects of this project included connecting and programming a variable speed drive and AC motor to control the speed of the mill rolls, simulating the behaviour of the integrated SPS-type sintering circuit using Simulink, designing a suitable method for safely and effectively transmitting the large SPS current to the rotating rolls, and building and testing the circuit for titanium compact spark plasma sintering. The manufactured direct powder rolling mill compacts titanium powder into strip through a pair of rolls, measuring 350mm diameter and 50mm width. Each of the rolls is mounted on the same shaft as a worm-driven gear. A 5.5kW three phase AC motor drives the worm shafts, which have opposing threads to ensure the rolls rotate in opposing directions. The worm and gear arrangement serves to both evenly transmit the drive power to both rolls, and to increase the torque from the motor to the rolls. The motor is controlled using a variable speed drive – this allows the roll speed to be adjusted as necessary, to optimise the consolidation process. The bearings used on the roll and worm shafts were designed and manufactured using an insulating bearing material to ensure the current used for sintering is not instead transmitted through the steel rolling mill frame. Flexible couplings with polymeric inserts isolate this current from the motor and between each worm gear. The minimum density of the green compact required for further handling was determined empirically as being greater than 65 % of the theoretical density of titanium. The mill was designed for an optimal density of 81%. The density range achieved by varying the parameters of roll speed, number of passes through the mill, and roll gap, was 55 – 84%. It is expected that the strip density may be greatly increased with implementation of the improvements and parameter changes identified. The spark plasma sintering circuit sinters the titanium either during the direct powder compaction process (simultaneous DPR-SPS), or following it (sequential DPR-SPS) during re-rolling through the same set of rolls used for compaction. A number of electrical circuits with different output types were designed for the SPS process; one of these was built and tested towards proof of concept of the DPR-SPS process. The tested circuit uses a DC source to apply a sintering current through the titanium sample. Application of the SPS current to the titanium resulted in a theoretical density increase of 11 –14% compared to DPR only, depending on whether the processes were performed sequentially orsimultaneously This multidisciplinary project employed a broad range of combined materials, mechanical and electrical design and analysis methods. The resulting mill can be used as is for further parametric testing, improved as will be discussed for the same process, or adapted to a range of different applications

Reverse engineering and refurbishing of an Mi-24 helicopter main gear box

The Mi-24 helicopter is one of the most famous heavy lift helicopters designed with a net weight of 8.4 tonnes, while its gross weight is 12.5 tonnes. This helicopter is powered by two TV3-117 turbo-engines, coupled to a VR-24 main rotor transmission gearbox, which reduces the engine speed from 15000 Revolutions Per Minute (RPM) to the main rotor speed of 240 RPM. This research aims to show the functionality of the Mi-24 helicopter main gear box, to find the opportunities to extend the running hours (before maintenance) and to refurbish the gear box locally in South Africa. The research follows the principles of Reverse Engineering (RE) and Refurbishing. The principles involve the extraction of information from an existing product in order to establish its function and to re-create specifications which can be used to make, maintain or refurbish a similar or superior item. This dissertation has exposed some of the theory of the design of the Mi-24 main gearbox components and their functionality; including similar selected helicopters’ main drive mechanisms. The probable defects that are common to helicopter transmissions, the specifications and the Computer Aided Design (CAD) drawings are also presented. The research concludes that, with the cooperation of the local aerospace industry (including the army), the academic institutions and government; it is possible to get the necessary certification, licensing, training, specialised equipment and to establish a Maintenance Organisation, to refurbish the Mi-24 helicopter gearbox locally in South Africa

Reverse engineering and refurbishing of an Mi-24 helicopter main gear box

The Mi-24 helicopter is one of the most famous heavy lift helicopters designed with a net weight of 8.4 tonnes, while its gross weight is 12.5 tonnes. This helicopter is powered by two TV3-117 turbo-engines, coupled to a VR-24 main rotor transmission gearbox, which reduces the engine speed from 15000 Revolutions Per Minute (RPM) to the main rotor speed of 240 RPM. This research aims to show the functionality of the Mi-24 helicopter main gear box, to find the opportunities to extend the running hours (before maintenance) and to refurbish the gear box locally in South Africa. The research follows the principles of Reverse Engineering (RE) and Refurbishing. The principles involve the extraction of information from an existing product in order to establish its function and to re-create specifications which can be used to make, maintain or refurbish a similar or superior item. This dissertation has exposed some of the theory of the design of the Mi-24 main gearbox components and their functionality; including similar selected helicopters’ main drive mechanisms. The probable defects that are common to helicopter transmissions, the specifications and the Computer Aided Design (CAD) drawings are also presented. The research concludes that, with the cooperation of the local aerospace industry (including the army), the academic institutions and government; it is possible to get the necessary certification, licensing, training, specialised equipment and to establish a Maintenance Organisation, to refurbish the Mi-24 helicopter gearbox locally in South Africa