A framework for optimized brake actuator design for heavy vehicle active safety

Abstract

Active Vehicle Safety Systems (AVSS) play a pivotal role in enhancing road safety by reducing accident-related fatalities, particularly in Heavy Commercial Road Vehicles (HCRVs), which predominantly employ pneumatic braking systems. The effective performance of these systems hinges on the availability of fast-acting actuators capable of delivering precise pressure control. This study presents a framework for optimization of an existing actuator valve to improve its responsiveness and fidelity for AVSS applications, with adherence to the automotive braking standard IS 11852. A physics-based model of the actuator valve was developed to identify critical design parameters that influence its dynamic performance. Subsequently, an extensive Design of Experiments (DoE) methodology was employed to determine the optimal valve geometry. Evaluation of the optimized valve on a Hardware-in-the-Loop (HiL) setup demonstrated a significant improvement in performance, with reductions of 35.8% and 45.6% in brake apply and exhaust times, respectively, relative to the baseline valve achieved without compromising adherence to the IS 11852 standard. These enhancements in valve response translated into notable improvements in Antilock Brake System (ABS) performance, yielding a 9.3% reduction in stable braking distance and an 8.2% increase in Mean Fully Developed Deceleration (MFDD). Furthermore, these performance gains were validated through on-vehicle testing on a single-unit 4 × 2 19-tonne vehicle. Upon evaluation in an unladen vehicle on high-friction surfaces, a commonly encountered critical braking condition, the optimized valve achieved a 6.8% reduction in stable braking distance and a 3.7% increase in MFDD. These results affirm the practical viability and performance advantages of the optimized valve design for AVSS integration in HCRVs.