Design of a prototype braking simulator

Abstract

This paper describes the fundamental design aspets and subsequent development of an elaborate laboratory rig for the accurate measurement of braking system performance. It consists of a fully-instrumented moving stainless steel belt assembly with superimposed texture passing over end pulleys and driven by a variable speed motor. The test wheel forms part of a test axle having torisional strain gauges, a partial drum brake, a slip-ring assembly, a rotational accelerometer unit, a speed sensor and a variable-inertia disc mounted in line. The stimulator permits as many as ten variables to be preset independently prior to or during any test run. The rig can be used to simulate hydroplaning behaviour and to test tread pattern design, and also to evaluate the effectiveness of locked-wheel, constant slip and anti-skid pulsed braking systems. The entire wheel support system can be removed if desired, and a second super-structure substituted to evaluate the high-speed friction and wear behaviour of tread rubber and plastic block samples