A study has been undertaken to determine the dynamic wheel loading characteristics of various heavy vehicle suspensions common to Canadian trucks. Three generic types of trailer suspensions and two types of tractor suspensions were examined. Variations in suspension axle spacing were included in the program.
The principle requirement of the study was to produce data on the magntidue of dynamic loading from all axles, on a typical tractor-semitrailer over representative roads at normal operating speeds.
To optimize control over various vehicle parameters during the test program, a tractor-semitrailer highway transporter was modified to allow for the exchange of different suspensions and to allow for changes in the inter-axle spacing.
Instrumentation techniques were used to measure vertical dynamic wheel loads, vertical axle acceleration, and brake torques from all major axles, simultaneously. All data was recordedon board the vehicle in the analog state.
This paper will discuss the vehicle modifications, instrumentation techniques and the methods of analysis used. In addition, a discussion of some of the trends that were observed during the experimental program will be presented.