Driving Assist System for Ultra-Compact EVs―Fundamental Consideration of Muscle Burden Owing to Differences in the Drivers’ Physiques

Abstract

With recent advances in technologies such as those of semiconductors and actuators, easy-to-control compact actuators have been actively applied in various fields such as factory automation and precision machining. In the automobile industry, major manufacturers and venture companies are also concentrating on electric vehicle development. Ultra-compact mobility vehicles, which exhibit an excellent environmental performance and are highly convenient for short-distance movement, are becoming popular. However, owing to cabin space limitations, it is difficult to mount systems such as power steering for assisting steering operations, and such systems are currently not installed in most ultra-compact mobility vehicles. Our research group focused on a steer-by-wire system that does not require a physical connection between the steering wheel and the wheels. Using this system, the steering wheel can be installed without any constraints, and the cabin layout can be easily changed. The reaction torque applied to the steering wheel can be expected to provide an optimum steering feel to each driver by controlling the reaction-force-generating actuator output. Drivers with different heights and arm lengths were then grouped, and arm model calculation and electromyogram measurements obtained during steering operations were used to examine the muscle burden experienced during driving owing to differences in the drivers' physiques.

Design and Evaluation of a Surface Electromyography-Controlled Steering Assistance Interface

“…Although sEMG electrodes have been used to reliably control prosthetic limbs and to objectively evaluate the muscle burden, steering comfort, and the time for drivers to apply force on steering wheels during vehicle turning maneuvers, few studies have investigated sEMG controlled steering as a means of assisting drivers with disability [14,15,16,17,18,19,20,21,22,23,24]. In contrast, other sensors such as joysticks, strain gauges and motion detectors have been developed [25,26,27,28,29].…”

Surface Electromyography-Controlled Automobile Steering Assistance

“…Since the COMS B•COM, a small-scale electric automobile by Toyota Auto Body Co. that is henceforth referred to as the 'COMS', has been employed in other studies to develop steering systems, the COMS is a suitable platform for developing an sEMG-controlled interface, as shown in Figure 1 [31][32][33][34]. The measurement of sEMG was realized with the Myo armband, a commercially available sEMG interface device that was introduced in 2013 by Thalmic Labs, Inc., Waterloo, ON, Canada [24].…”

A Basic Study for Active Steering Wheel System for Steering Burden Evaluation by Driving Position Focus on Driver’s Arm Size

“…We consider that the size of arms, range of motion and muscle mass of the arm, which differ depending on the person, affect the steering feel and burden and consider the driving position that can appropriately control the vehicle [20,21]. Although there have been studies on the effects of the driving position on the steering burden [22][23][24][25][26][27][28], there have been no studies that take into account conditions with a steer-by-wire system or low steering gear ratios.…”