This report describes the development and experimental validation of a coordination scheme between friction and discretely variable compression brakes for a Class 8 Freightliner truck used as a development platform in the California PATH program. The coordination scheme that we developed maintains the speed tracking performance of the nominal PID controller which was originally designed by the ...

Brake squeal relating to the application of tread block brakes on rail cars can generate significant noise annoyance issues and presents a challenging problem due to the associated technical complexities as well as inherent design constraints. In this paper the phenomenon of brake squeal occurring on a rail vehicle is investigated using experimental techniques. The operational vibration respons...

The friction forces generated during braking between brake pads and discs produce high thermal gradients on the rubbing surfaces. These thermal gradients may cause braking problems such as brake fade, premature wear or hot spotting and the associated hot judder phenomenon in the frequency range below 100 Hz. Further consequences are comfort reductions, a defective braking process, inhomogeneous...

In order to improve the response performance of a proportion integration differentiation (PID) controller for magnetorheological fluids (MRF) brake and to reduce the braking fluctuation rate, an improved fruit fly optimization algorithm for PID controller parameters tuning of MRF brake is proposed. A data acquisition system for MRF brake is designed and the transfer function of MRF brake is ide...

In any brake system of an automobile or passenger vehicle, an increase in Master/Wheel cylinder diameter ratio leads to an increase in brake efficiency. This paper focuses on Master/Wheel cylinder diameter effect on the brake efficiency. A VISUAL BASIC computer code was developed for computation of Master/Wheel cylinder diameter ratio corresponding to break efficiency. Aided by the developed so...

Rear-end collisions and distraction are major concerns and basic research in cognitive psychology concerning attention in visual search is applicable to these problems. It is proposed that using yellow tail lamps will result in faster reaction times and fewer errors than current tail lamp coloring (red) in detecting brake lamps (red) in a "worst case" scenario where brake lamp onset, lamp inten...

Standard incandescent brake lamps have a relatively slow rise time. It takes approximately a quarter of a second for them to reach 90% of asymptotic light output, causing potential delays in responses by following drivers. The present study evaluated reaction times to brake signals from standard incandescent brake lamps and from three alternative brake lamps with substantially faster rise times...

Rear-end collisions and distraction are major concerns in automotive transportation. This study investigated the conspicuity of current rear automobile lighting (red brake and red tail lamps) compared to a proposed arrangement (red brake lamps with yellow tail lamps) in a task where participants only had time to perform one saccade and fixation (200ms) to identify the presence or absence of bra...