Environment adaptation of a new staircase-climbing wheelchair
This paper describes the mechanical devices conforming a novel wheelchair prototype capable of climbing staircases. The key feature of the mechanical design is the use of two decoupled mechanisms in each axle, one to negotiate steps, and the other to position the axle with respect to the chair to accommodate the overall slope. This design simplifies the control task substantially. Kinematic models are necessary to describe the behavior of the system and to control the actuated degrees of freedom of the wheelchair to ensure the passenger's comfort. The choice of a good climbing strategy simplifies the control and decreases the power consumption of the wheelchair. In particular, we demonstrate that if the movement of the wheelchair has the same slope as the racks or the same slope as the terrain that supports the wheel axles (depending on the configuration mechanism), control is easier and power consumption is less. Experimental results are reported which show the behavior of the prototype as it moves over different situations: (a) ascending a single step of different heights using different climbing strategies; and (b) climbing a staircase using an appropriate climbing strategy that simplifies the control and reduces the power consumption of the wheelchair.
environment adaptation wheelchair kinematic model stair climbing trajectory generation