Control for four‐wheel individual steering and four‐wheel driven electronic vehicle

Abstract

SUMMARYAn indoor four-wheel individual steering and driving vehicle with full electronics was built for evaluation of the system's ability and the performance in practical use. Mechanical parts such as the connecting rod and the differential gear are not provided for this vehicle.From trial operation, the characteristics fully performed as in design, but some problems originating from the design concept were disclosed.Rotating radius (R) of the vehicle was taken for the steering command parameter, but it was found to not be an appropriate parameter for driving operation. The reasons are as follows:1) R has a much different sense of driving conformability for the driver, because it does not refer to the running direction, but to the rotating radius of crosswise direction.2) Sensitivity of each wheel steering angle versus R differs over double figures in the full range of R.3) R changed from plus to minus and also vice versa in most practical situations around straight-go operation.For these reasons, the steering command parameter was changed from R to α, where α is the angle between the vehicle lengthwise direction and the moving direction. The steering control algorithm using α has been proven to solve the three above-mentioned problems.

Distributed coordination and environmental load distribution control for omni-directional vehicle

“…ボットなど幅広い分野への応用(北川他，2005) (鈴木他，2009) (今井他，2009) が期待で きる．二次元平面を任意の方向へ移動可能な車両はホロノミック型と呼ばれ，従来研究の多くは ODV を実現す るために特殊な車輪，または機構を開発することが多い(多田隈，2011) ．しかし，特殊車輪は複雑な構造ゆえに 耐久性や安定性に欠けるため，車両の大型化や高速化が困難である(山下他，2003) ．一方，非ホロノミック型(森 他，1998) ) ( Nie, et al, 2012) (Choi, et al, 2008) ( Oshima, et al, 2005) If it moves without the angle being ready, there is a possibility to hang load to each vehicle part. The wheel modules begin movement after changing the attitude angle and waiting for the ready of all module's angle.…”