Evaluation of Differential Steering Performance in VRU Testing Platforms: Accuracy and Reliability Analysis Across Varying Speeds and Circular Trajectories

Abstract

This study investigates the performance of differential steering systems in navigating circular trajectories at varying speeds using a small Vulnerable Road User (VRU) testing platform. The platform, designed with two 600W Brushless Direct Current (BLDC) hub motors and a differential steering mechanism, was evaluated for its accuracy and reliability in following designated paths with radii of 4, 8, and 12 meters. The evaluation was carried out at two motor speeds 5 000 and 10 000 rpm. Significant deviations from the intended path were observed, with deviations ranging from 14.0% to 32.3%, particularly at higher speeds and larger radii. The primary cause of these deviations was identified as wheel slippage on the asphalt surface, worsened by centrifugal forces during turns. Despite these challenges, the steering system demonstrated good reliability, maintaining deviations within 10%. The study underscores the need for optimizing wheel materials and refining control algorithms to reduce slippage and improve maneuverability. These findings offer valuable insights into enhancing the accuracy of differential steering systems in VRU testing platforms, contributing to the development of more effective Advanced Driver-Assistance Systems (ADAS).