The focus of the work in this thesis is concerned with the investigation and development of indirect measurement techniques. The methodology adopted is a combination of practical experimental, analytical deductive reasoning and simulation studies. This has led to proposals for a number of indirect tyre pressure monitoring systems, which are able to detect pressure loss under specific circumstances. The outcome overall is a proposal for a new supervisory system comprising of a modular framework, allowing various algorithms and techniques to be implemented in a complementary manner as they emerge and data sources become available. A number of contributions to the field have been made, which to the knowledge of the author, provide potential for further algorithm development and are imminently applicable given the above. The methods include a tyre pressure diagnosis via a wheel angular velocity comparator, the development of a model-based tyre pressure diagnosis via application of an unknown input observer and a parameter estimation scheme, a model-based tyre pressure diagnosis approach via an enhanced Kalman filter configured to estimate states including the input, a model-based tyre pressure diagnosis via cautious least squares, an investigation and critique of the effects of the choice of sampling interval on discrete-time models and estimation thereof. It is considered, that the extensive literature review provides a valuable historic insight into the tyre fault detection problem. It is clear, from the development and testing of the algorithms (and also the literature), that no single indirect pressure detection method is able to reliably detect changes in all driving scenarios which the regulations typically stipulate (depending on jurisdiction). In the absence of any information about the road input, the majority of the detection work must be shouldered by the wheel angular velocity comparator algorithm. As image recognition and sensor technology develops, it becomes possible to make estimates about the road surface and this removes some of the uncertainty on the input of the model-based parameter estimation approaches. Further work is detailed which goes some way towards realising the next steps in a development cycle suitable for a vehicle manufacturer to take through to the implementation stage.

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This thesis deals with the radial stiffness of a tyre. The first part of is devoted to a brief description of a tyre construction. The next part is devoted to measuring the radial stiffness of a tyre and the design of a new measuring device. The last part of the thesis deals with the influence of the radial stiffness of a tyre on the vertical dynamics of ta vehicle and simulations of this effect in the MATLAB / Simulink software.

Exterior vehicle noise has a very big impact when it comes to environmental noise pollution. Due to the decrease of the other noise sources of a passenger car, like power-train and air turbulence noise in the last decade, the tyre/road noise has become a more important part in the overall noise generation of a vehicle nowadays. It is considered as the main noise source in nearly all driving conditions, especially with increasing vehicle speed. The easiest idea to tackle this pollution is to introduce rules like speed-limits to control the noise at a certain area or time. More interesting, however, is to approach the problem of unwanted noise directly at the source. This Thesis, carried out at Loughborough University, aims to give a better understanding about the basic noise generation mechanisms at the tyre/road interface. Especially, the air related mechanisms of closed cavities are analysed. With the usage of a solid rubber tyre, unique measurements have been carried out and the results are compared to the theories already existing in the literature. These measurements reveal some of the strengths and weaknesses of the current understanding of air related noise generation.

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In this work, an investigation on the fraction of tyre pyrolysis oil with a similar distillation range to that of automotive diesel (150 – 360 oC) was carried out to determine its suitability as an alternative or additive to petro-diesel fuel. The quality of this oil was evaluated by comparing its key properties to the requirements of South African National Standards for Automotive diesel fuel (SANS-342) and to conventional automotive diesel fuel. The viscosity, density, copper strip corrosion of this fuel were found to be within the acceptable limits set by SANS while sulphur content and flash point were out of their respective set limits. In addition, mixing rule equations for predicting viscosity and density for both pure and blends of the oil as a function of temperature were developed and evaluated. The equations were found to be suitable due to their low Absolute Percentage Deviation. Engine performance tests were carried out with blends of Distilled Tyre Pyrolysis Oil (DTPO) and petro-diesel fuel in a single cylinder air cooled diesel engine. The performance, emission and combustion characteristics of the diesel engine while running on these blends were evaluated and subsequently, a comparative analysis was performed with conventional petro-diesel fuel as the reference fuel. It was found that, the engine could run with up to 60% (DTPO) without any problem. Beyond this level the engine became unstable. The power and torque were similar at low and medium speeds. However, at high speeds, the power dropped with increase in DTPO in the blend. Fuel consumption was very comparable for all the test fuels. Carbon monoxide and unburned hydrocarbons were higher for the blends compared to petro-diesel fuel but oxides of Nitrogen were lower. The peak pressure for petro-diesel fuel was marginally higher than that of the blends. Present results indicate that, petro-diesel fuel can be blended with up to 60% DTPO and produce acceptable performance. Testing the diesel engine under different operating conditions is a time consuming and expensive process that also requires the use of specialised equipment which may not be readily available. An Artificial Neural Network (ANN) model based on a back-propagation learning algorithm was developed to predict engine performance and emissions separately, based on fuel blend and speed. The performance and accuracy of the model were evaluated by comparing experimental and ANN predicted results. The ANN was able to predict both engine performance and emissions with acceptable levels of accuracy. The values of correlation coefficient between experimental and predicted data being greater than 0.99. From this work, it can be implied that engine emission and performance can be predicted using neural network-based mode, consequently, it will be able to do further investigations without running laboratory experiments. Energy recovery from waste is an interesting field for engineers and scientists. It is hoped that this work will prompt new research ideals on how tyre pyrolysis oil can be improved for use as diesel engine fuel and building better models for diesel engine performance and emissions

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Many companies have performance management systems that incorporate financial and non-financial measurements. All organisations have financial and non-financial measures. However, many use their non-financial measures for local improvements at their front-line and customer-facing operations. Performance management is a shared process between managers and the individuals and teams they manage. It is based on the agreement of objectives, knowledge, skill and competence requirements and work and development plans. The Balanced Scorecard includes financial measures that reflect the results of actions already taken, complementing the financial measures with operational measures on customer satisfaction, internal processes, and the organisation’s innovative and improvement activities. The Balanced Scorecard combines both quantitative and qualitative measures, acknowledge the expectations of different stakeholders and relate an assessment of performance to choice of strategy. The objective of this study was to assess current performance management that is applied within the manufacturing division at Continental Tyre South Africa. To achieve this objective, a comprehensive literature study was performed on performance management and The Balanced Scorecard. A questionnaire was designed based on the guidelines in the literature study in order to establish the extent to which Continental Tyre South Africa manages performance. The researcher used the random sampling method of selection and distributed the questionnaire to 120 potential respondents via electronic mail and physically. Seventy seven completed questionnaires were returned and these were processed and analysed using Microsoft Office Excel 2003, iii running on the Windows XP suite of computer packages. The opinions of the various respondents were compared with the guidelines provided in the literature survey in order to identify shortcomings of performance management and the achievement of individual and departmental objectives within the manufacturing division at Continental Tyre South Africa. The following main recommendations were made: Continental Tyre South Africa should continue with the sharing of its strategic objectives with management and staff, and must ensure that these objectives are also shared all the way down to the shop floor; It is imperative that management and staff mutually agree on performance objectives for the individuals; Senior management must measure management and staff on how well they performance manage their direct reports and develop people where performance short-comings exist; It is imperative that management and staff undergo performance management training; Management must ensure that there current performance management system incorporates a method to distinguish between top and poor performers; and, It is advisable that senior management consider a mechanism that rewards top performers.