Search Results

This paper describes the application of an Active Thermal Imaging technique (ATI), whereby a temperature gradient is produced by the operation of the braking system in use, to determine thermal brake imbalance. Results obtained from passenger vehicles and heavy goods vehicles (trucks) are detailed, showing how side-to-side thermal imbalance can be quickly and quantitatively recorded at the roadside.

Modern automotive engine design is making the measurement of engine speed increasingly difficult, due to problems with access for the sensors and, hence, forms the motivation for this investigation. Some manufacturers provide a dedicated pin/socket for engine speed, but this is clearly vehicle specific and may not always be accessible. A novel method is described for the measurement of the speed of a reciprocating internal combustion engine, based on the analysis of the vibration of the engine block using an accelerometer. The Power Spectral Density (PSD) derived from the accelerometer signal contains a dominant peak of which engine speed is a multiple, and it is possible to track this peak over the engine speed range. Whilst initially developed for diesel engine application, the range of application has been extended to petrol engines, and hence the device can be truly described as a universal tachometer.