This thesis presents a study of a novel suspension system which is placed inside a vehicle's wheel. The In-wheel suspension system isolates the sprung mass from excitations similar to conventional suspension systems. In traditional suspension systems the isolation is provided by spacious and complicated mechanisms, and mainly in the vertical direction. However, the in-wheel suspension system, not only fits the suspension mechanism inside the unused space between a wheel’s rim and hub, but also allows for isolation both in vertical and horizontal directions. The main focus of this thesis is to study, investigate, and show the feasibility of applying such suspension system to a vehicle. This research is conducted on low speed, low load, and non-powered vehicles such as hand trucks and baby strollers. This helps to escape from the complications of a complex system like a road vehicle. It also demonstrates the versatility of the in-wheel suspension idea. The objective of the project is to scrutinize a simple but practical in-wheel suspension system and demonstrate its applicability. The research begins with the dynamics modeling of an in-wheel suspension system. This suspension has been previously developed at the University of Waterloo for a wheelchair. The dynamics model evaluates the response of the suspension system and investigates the influence of various design parameters on the in-wheel suspension. The study is then continued to improve the design by replacing its rigid mechanism links with optimized compliant structures. This reduces the system's complexity and weight while boosting its performance. Furthermore, a general optimization code is developed to design and optimize flexible members for in-wheel suspension systems. The optimization program is then used to design and optimize two prototypes for hand trucks. Finally, the in-wheel suspension system for a hand truck is tested and evaluated. The experimental results also verify the simulation results and verify the developed optimization design program.

This thesis presents a study of a novel suspension system which is placed inside a vehicle's wheel. The In-wheel suspension system isolates the sprung mass from excitations similar to conventional suspension systems. In traditional suspension systems the isolation is provided by spacious and complicated mechanisms, and mainly in the vertical direction. However, the in-wheel suspension system, not only fits the suspension mechanism inside the unused space between a wheel’s rim and hub, but also allows for isolation both in vertical and horizontal directions. The main focus of this thesis is to study, investigate, and show the feasibility of applying such suspension system to a vehicle. This research is conducted on low speed, low load, and non-powered vehicles such as hand trucks and baby strollers. This helps to escape from the complications of a complex system like a road vehicle. It also demonstrates the versatility of the in-wheel suspension idea. The objective of the project is to scrutinize a simple but practical in-wheel suspension system and demonstrate its applicability. The research begins with the dynamics modeling of an in-wheel suspension system. This suspension has been previously developed at the University of Waterloo for a wheelchair. The dynamics model evaluates the response of the suspension system and investigates the influence of various design parameters on the in-wheel suspension. The study is then continued to improve the design by replacing its rigid mechanism links with optimized compliant structures. This reduces the system's complexity and weight while boosting its performance. Furthermore, a general optimization code is developed to design and optimize flexible members for in-wheel suspension systems. The optimization program is then used to design and optimize two prototypes for hand trucks. Finally, the in-wheel suspension system for a hand truck is tested and evaluated. The experimental results also verify the simulation results and verify the developed optimization design program.

For the requirements of high-speed signal transmission has been increasing, the fiber array in the communication system has a lot of advantages which can not be replaced. But the loss of coupling efficiency is a difficult problem as the distance of communication is getting longer and longer. For the sake of solving this problem, the system needs to use optic amplifier for enlarging the coupling efficiency in every long distance. The receiver can receive the correct signal by using optic amplifier. In order to reduce the using amount of optic amplifier for decreasing the cost, producing the fiber array with high coupling efficiency can reach the goal. This paper chooses quadrangular-pyramid-shaped fiber endface (QPSFE) which has better coupling efficiency than flattened-end fiber to research. Among those different manufacturing methods and different precision for fiber array packaging, the research chooses the method of grinding to manufacture the shape of surface. The research can raise the accuracy of manufacture for increasing the coupling efficiency of QPSFE by external equipments.

¡@¡@This study provides static and dynamic analysis of three-wheel stroller which is marketed. The model of stroller is built by computer- aided design software SolidWorks for perform static analysis on finite element analysis software ANSYS and mechanism¡¦s dynamic analysis on directed computer-aided mechanism analysis software COSMOSMotion. ¡@¡@It is important of stroller safety because it carry tender babies. The stroller should be examined carefully with three-wheel stroller always used on outdoor. CNS 6263 provides the standard for the safety test on the structure of the stroller, which includes a static analysis. In order to offer absolute safety for stroller, CNS uses a high standard to test the sample. For the market permission, the stroller needs to pass the CNS test, company always let stroller too strong to pass the test, and that will let the volume and weight too large to burden with cost. In this thesis, the researcher discussed the different on stroller between the traditional design and the CNS standard design. He also made an assumption the check if the stroller is overdesign. ¡@¡@A three-wheel stroller is a jogging stroller, and it is usually used on high velocity. Manufacturer should consider its steady, especially when the mass center of three-wheel stroller is usually too high. Dynamic analysis in this study will discuss the effect on the stroller when the forces of user are applied on the stroller. By the rollover formula of the three-wheel car, this study modified the program for three-wheel stroller in order to consider the influence of the force on the stroller. Comparing the results between the simulation of software and the calculation of the rollover function of three-wheel stroller, this study provides models for designers to prevent the rollover from the stroller.

This thesis presents the work undertaken to assess potential improvements in high performance bicycles. There are several wheel options available for elite riders to use in competition and this research has investigated the aerodynamic properties of different wheel type. The research has also developed CFD and FEA models of carbon fibre bicycle wheels to assist in the wheel improvements process. An accurate and repeatable experimental test rig was developed to measure the aerodynamic properties of bicycle wheels in the wind tunnel, namely translational drag, rotational drag and side force. Both disk wheels and spoked wheels were tested. It was found that disk wheels of different hub widths have different aerodynamic properties with the 53mm wide Zen disk wheel requiring the lowest total power of the wheels tested. There was little difference between the translational power requirements of the wheels but there was greater variation in the rotational power requirements. Compression spoked wheels of 3 and 5 spokes were found to require less power than wire spoked wheels. There was little difference between the total power requirements of the compression spoked wheels tested, with the differences at 50km/hr being less than the experimental uncertainty. The Zipp 808 wheel demonstrated considerably lower axial force than all other wheels at 10° yaw angle, confirming Zipp design intention to have optimum wheel performance between 0-20°. The Zen 3-spoke wheel showed the lowest axial drag and side force at yaw of the compression spoked wheels tested and had similar side force results to the Zipp 808. CFD models of the disk and 3-spoke wheel achieved good agreement with the experimental results in terms of translational drag. Rotational drag did not agree so well, most likely due to the turbulence model being designed for higher Reynolds number flows. A FE model of the disk wheel was validated with experimental testing. In order to simplify modelling, the FE model of the 3-spoke wheel did not include the hub, which led to a large discrepancy with experimental results for the particular loading scenario. The experimental rig and CFD models were used to develop aerodynamic improvements to the wheel and the FE models were used to identify the implication of geometric changes to the wheel structural integrity. These improvements are not reported in this thesis due to the results being commercially sensitive.

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To attract more customers and compete with other modes of transportation, railway transport needs to ensure safety, punctuality, high comfort, and low cost; wheel–rail adhesion, i.e., the transmitted tangential force in the longitudinal direction during driving and braking, plays an important role in all these aspects. Adhesion needs to be kept at a certain level for railway operation and maintenance. However, wheel−rail contact is an open system contact. Different contaminants can present between the wheel and rail surfaces, forming a third-body layer that affects the adhesion. Prediction of wheel–rail adhesion is important for railway operations and research into vehicle dynamics; however, this prediction is difficult because of the presence of contaminants. This thesis deals with wheel–rail adhesion from a tribological perspective. The five appended papers discuss wheel–rail adhesion in terms of dry conditions, lubricated conditions, leaf contamination, iron oxides, and environmental conditions. The research methodologies used are numerical modelling, scaled laboratory experiments, and field tests. The research objective is to understand the mechanisms of the adhesion loss phenomenon.  A numerical model was developed to predict wheel–rail adhesion based on real measured 3D surfaces. Computer simulation indicates that surface topography has a larger impact on lubricated than on dry contacts. Plastic deformation in asperities is found to be very important in the model. Ball-on-disc tests indicate that water can give an extremely low adhesion coefficient on smooth surfaces, possibly due to surface oxidation. Investigation of lubricated contacts at low speed indicates that oil reduces the adhesion coefficient by carrying a normal load, while adhesion loss due to water depends on the surface topography, water temperature, and surface oxidation. A field investigation indicates that leaves reduce the friction coefficient because of the chemical reaction between leaves and bulk materials. The thickness of the surface oxide layer was found to be an essential factor determining adhesion reduction. Pin-on-disc experiments found a transition in the friction coefficient with regard to the relative humidity, due to a trade-off between the water molecule film and the hematite on the surface. / <p>QC 20131031</p>

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This master thesis focuses on design of steering wheel and clutch controller module for Formula Student car, The first part of this thesis is focused on communication protocol CAN and continues with explanation of reasons for development of this solution. Requirements for individual components of system are introduced in next part. At the end of the thesis the final electrical and hardware design is introduced as well as software design. The last part of this thesis is focused on simulation of system in race condition and evaluation of results.

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