Development of a driving assist system for ultra-compact electric vehicles using a steer-by-wire system: Fundamental consideration of muscle burden and evaluation by a continuous steering operation

Abstract

Ultra-compact electric vehicles has excellent environmental performance and are extremely convenient for short-distance travel. However, owing to cabin space limitations, it is difficult to mount power steering. Therefore, there is a need to increase the gear ratio of the rack and pinion to change steering angle because such vehicles need light torque to steer. However, increasing the gear ratio requires more rotations of the steering wheel. Our research group focused on developing a steer-by-wire system (SBWS) that freely controls the steering torque. Although we evaluated the burden when a driver rotates the steering wheel in one direction in a previous study. This study assumed the actual steering operation in an SBWS. And then we evaluate muscle burden when a driver steers with continuous changing of the steering direction.