<p>For every operating condition of an internal combustion engine there exists an optimal spark timing, called maximum brake torque (MBT), which maximises the output torque and the efficiency of the engine. Traditionally MBT timing is implemented as an open-loop control where the ignition timing is found by using a combination of static lookup tables and sensor information. With a direct closed-loop control from the combustion process the performance of internal combustion engines could be improved. The thesis investigates if it is possible to estimate the MBT timing from the ionization current for every operating condition of a spark ignited engine where the operating conditions are defined by the engine parameters lambda, internal exhaust gas recirculation, engine load, engine speed and spark advance.</p><p>First an investigation of how much loss of torque an error from the MBT position corresponds to is made. Then the influence of the engine parameters on the shape of the ionization current was studied. Last different peak pressure position (PPP) estimating algorithms are presented and a new technique is developed where an engine operating point dependant part of the ionization current is used depending on the current operating condition of the engine. Two of the presented PPP estimating algorithms are then complemented with this technique and the results look promising.</p>

The objective of the present work is to study the vehicle suspension as a vibro-acoustic system of high complexity, consisting of many sub-systems with fundamentally different acoustical properties. In a parallel numerical and experimental modelling effort, important contributions to the understanding of its behaviour have been achieved. These findings are based on a balance between component investigations and global modelling of the complete system; they have been formulated for the transmission of both tyre-road excitation and friction-induced vibrations in the brake system. Initially an experimental study was conducted on a full vehicle test rig studying the broadband interior brake noise problem of, here named, roughness noise. The purpose of the study was twofold: first, to determine if the transmission from the source to the interior of the vehicle was structure-borne; second, to study the complexity of the suspension as a vibro-acoustic system. Parameters a_ecting the vibro-acoustic source were varied to gain understanding of the source mechanisms. This experimental study laid the foundation of the first part of this thesis (paper A) and provided the directions for the second part, the development of a mathematical modelling approach (paper B and C). In these two papers, methods for analysing the complex vibro-acoustic transfer of structure-borne sound in a vehicle suspension system were developed. The last part was then focussed on the wheel rim influence on the vibro-acoustic behaviour (paper D) of the suspension system. As a whole, the work clearly demonstrates that it is possible to conduct component studies of subsystems in the vehicle suspension system; and from these component studies it is possible draw conclusions that very well may avoid severe degradations in the interior noise of future vehicle generations. / <p>QC 20130503</p>

The purpose of this master thesis project has been to analyze and document the Sirius 2001 Concept Car. In addition, it has also been a goal to get the car in a usable state by implementing new software on the on board computers. The car is a Tiger Cat E1 that is modified with four wheel steering and an advanced X-by-Wire system. The computers in the X-by-Wire system consist of six TTP PowerNodes that communicate with each other over a redundant, fault tolerant TTP/C communications bus. The computers are connected to a number of sensors and actuators to be able to control the car. This project has contributed to the car in several ways. A complete documentation of the systems implemented in the car is one. Another is a programmers manual which significantly lowers the threshold when working with the car. Last but not least is the modifications in hardware and software, which have made the car usable and show some of the possibilities with the system. The results show that the Sirius 2001 Concept Car is a suitable platform for research in car dynamics and fault tolerant systems. The work has also shown that the TTP/C communication model works well in an application like this.

For every operating condition of an internal combustion engine there exists an optimal spark timing, called maximum brake torque (MBT), which maximises the output torque and the efficiency of the engine. Traditionally MBT timing is implemented as an open-loop control where the ignition timing is found by using a combination of static lookup tables and sensor information. With a direct closed-loop control from the combustion process the performance of internal combustion engines could be improved. The thesis investigates if it is possible to estimate the MBT timing from the ionization current for every operating condition of a spark ignited engine where the operating conditions are defined by the engine parameters lambda, internal exhaust gas recirculation, engine load, engine speed and spark advance. First an investigation of how much loss of torque an error from the MBT position corresponds to is made. Then the influence of the engine parameters on the shape of the ionization current was studied. Last different peak pressure position (PPP) estimating algorithms are presented and a new technique is developed where an engine operating point dependant part of the ionization current is used depending on the current operating condition of the engine. Two of the presented PPP estimating algorithms are then complemented with this technique and the results look promising.

Bibliography : leaves 238-262. / xxiii, 262 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 1995

I denna rapport redovisas fyra koncept för utveckling av en bromspedal, med målet att reducera godstjockleken från den befintliga pedalen som är 2mm till 1,5mm, men samtidigt behålla hållfastheten som den befintliga bromspedalen erhåller. Det ställs höga belastningskrav på bromspedaler, och att minska godstjockleken innebär högre påfrestningar på materialet.För att utveckla en ny konstruktion som skall leva upp till dessa krav har programvaran PTC Creo 3.0 använts, och för analysering av dessa koncept har verktyget Simulate använts.I resultatdelen simuleras och redovisas fyra koncept i 1,5mm plåt som jämförs i total förskjutning med originalpedalen i 2mm plåt. Slutsatsen är att de inte når upp till lika bra resultat som originalpedalen. Däremot med 1,9mm plåt når det resultatmässigt bästa konceptet (koncept 3) upp till ett bättre resultat än originalpedalen, och detta leder till en viss förbättring i minskning av material, med bibehållen hållfasthet. / This report describes four prototypes for the development of a brake pedal, with the goal of reducing material thickness from the the existing pedal from 2mm to 1.5mm, while maintaining the strength of the existing brake pedal. There are high load demands on the brake pedals, and to reduce the thickness means higher strain on the material.To develop a new design that will live up to these requirements, the design tool software PTC Creo 3.0 has been used, and the analysis of these structures has been performed using the tool Simulate in PTC Creo parametric.The result show four concepts presented and simulated in 1.5mm plate thickness, and the results are compared with the original pedal results in 2mm plate thickness regarding total displacement. The conclusion is that the concepts do not fulfill the load requirements.However with 1.9mm plate thickness, our best concept (concept 3) is fulfilling the loading requirements even better than the existing pedal, and that leads to an improvement regarding reducement of material, with retained strength.

Currently, the production of most non-asbestos organic (NAO) friction materials depends on a long and energy intensive manufacturing process and an unsustainable supply of synthetic resins and fibres; it is both expensive and bad for the environment. In this research, a new, more energy efficient, manufacturing process was developed which makes use of a naturally derived resin and natural plant fibres. The new process is known as 'cold moulding' and is fundamentally different from the conventional method. It was used to develop a new brake pad for use in low temperature (<400 °C) applications, such as rapid urban rail transit (RURT) trains. A commercially available resin based upon cashew nut shell liquid (CNSL) was analysed and found to have properties suitable for cold moulding. In addition, hemp fibre was identified as a suitable composite reinforcement. This was processed to improve its morphology and blended with aramid to improve its thermal stability. Each stage of cold mould manufacture was thoroughly investigated and the critical process parameters were identified. The entire procedure was successfully scaled up to produce an industrially sized 250 kg batch of material and the resultant composites were found to have appropriate thermal and mechanical properties for use in a rail brake pad. The tribological performance of these composites was iteratively developed through a rigorous testing and evaluation procedure. This was performed on both sub- and full-scale dynamometers. By adding various abrasives, lubricants, and fillers to the formulation it was possible to produce a brake pad with similar friction characteristics to the current market material, but with a 60% lower wear rate. In addition, this brake pad caused 15% less wear to the brake disc. A detailed examination of both halves of the friction couple found that cold moulded composites exhibit a different wear mechanism from the current market material, which was suggested to be the reason for their superior properties. Cold moulding is 3.5x faster and uses 400% less energy than the conventional method.

The project has been conducted in collaboration with the company Volvo Group Truck Technology and deals with the area of ​​brake development. The purpose of this thesis is to develop a simulation tool to perform rapid testing of the brake system.  The brake system is introduced, where an explanation of what the brake systems role is in the vehicle and which kinds of brakes can be found in commercial trucks. Different trucks depend on different braking systems, a truck doing long-hauls will have different braking needs than a worksite transporter. It is important to have a customizable tool to be able to cover the different truck braking systems.   Simulations cannot replicate reality perfectly; the results will always deviate from the actual value. There are countless of variables that can affect the braking torque, everything from mechanical efficiency to weather conditions. It is important to set limitations and boundaries for the tool.  Four different methods have been used to develop the simulation tool. MATLAB pulls information from component test data stored in Excel sheets, then inserts it into the block diagram calculations in Simulink where the model has been created using a data driven method with a physics base. The tool has also been validated compared to component performance data and old truck dynamometer tests.   The project presents how the development cost can be reduced by using the simulation tool instead of traditional testing. A simulation can be done in one minute, as opposed to the 14 days it takes to perform a physical test, this means that decisions can be taken quicker with minimal resource investments. The virtual vehicle customization is also presented, where the user can choose which specific components to test. Making the tool useful for different braking scenarios and different truck setups.

Evolution had played a significant role in structuring on how humans stand, walk or run. The nervous system plays a major role in the control of locomotion and injuries to the system can lead to gait abnormalities or disabilities. A Spinal Cord Injury (SCI) causes lack of signal communication between the central nervous system and the muscle fibers leading to deprived or no activation of the muscles thus resulting in paraplegia or quadriplegia. Over the past decade wearable robotics and exoskeletons have been gaining outstanding recognition in the field of medical, assistive and augmentative robotics and have led to numerous new innovative mechanisms in the mechanical engineering field. Due to fast paced research activities, the critical importance and performance of mechanisms such as wrap spring clutch/brake,Wafer Disc brakes are overlooked or used ineffectively. So, researchers tend to create new actuators from scratch and have limited their use of previously available resources, which has prevented us to explore the potential of these devices.The research presented focuses on developing a mechanism (“A Wrap Spring Clutch/Brake Mechanism”) from scratch using a trade study approach. This thesis addresses the fundamental relationship between coefficient of friction, interference, spring diameter and the holding torque of the mechanism using analytical, testing and simulation results. The human biomechanical data during ground level walking was used as design targets to develop the mathematical model of the system. Data from the testing stated that these targeted goals have been achieved by the design. This mechanism is used as a Knee Joint for the Hybrid EXoskeleton (HEX) GEN-1 project which is developed at the Automation and Interventional Medicine (AIM) Robotics Research Laboratory to rehabilitate the SCI.

This diploma thesis deals with the design of a universal muzzle device for the assault rifle. The device is designed to produce Selective Laser Melting. The main objective is the elimination negative effects of gunshot. The paper explores possibilities of using porous structures for this type of equipment. The influence of individual types of porous structures on the flow of gases is monitored. The universal muzzle device itself is optimized using CFD analyzes. The device was made using SLM technology and experimentally verified. His impact on the impact, gun lift, noise and flame elimination was investigated.