Active Seat Suspension for Ultra-compact Mobility with Small Motor

(Fundamental Consideration on Ride Comfort Improvement for Vibration in Two Directions)

Abstract

　Since the vehicle body of ultra-compact mobility is lightweight, there is concern about degradation of ride comfort due to vibration from the road surface. There have been reports on active seat suspension as a means of controlling vibration for occupant, however only in the vertical direction. In addition to vertical vibration, vibration in rotational directions such as roll, pitch, and yaw also deteriorate ride comfort. Furthermore, it has been reported that the human perception of vibration is different in the vertical direction with respect to frequency from that in the rotational direction, such as the pitch direction, which is input during acceleration. Therefore, this paper proposes an active seat suspension system that controls vertical and pitch vibration, and analytically clarifies the vibration characteristics of the model when the optimal control is applied. Furthermore, the output voltage of the voice coil motor of the active seat suspension is limited due to its small size. Therefore, the variation of the frequency response within the limited range was investigated.