Driving experiment of front drive type electric wheelchair using yaw-rate control

Electrical wheelchair has been used as a convenient transport device for elderly and handicapped persons. Recently, a front drive type electric wheelchair which is easy for handicapped persons to get on has been focused on. However, the front drive type electric wheelchair is difficult to run straight not only on slope but also on flat floor because of its over-steering characteristic. If wheelchair can be driven by easy stick operation, it will be a comfortable function for handicapped persons. To control the front drive type electric wheelchair, we have proposed a new control method which achieves the desired steering characteristic based on the internal model control. In this paper, we show driving experiments and evaluate the effectiveness of this method. First, dynamic characteristic of the wheelchair is clarified by simulation and driving experiments. Next, attitude control method of the wheelchair using yaw rate information is presented. Finally, the effectiveness of proposed method is confirmed by driving control simulations and experiments on slope, and the improvement of maneuverability is evaluated by motion of operation stick by driver.