Environment adaptation of a new staircase-climbing wheelchair

Abstract

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.

Control of a DC motor using algebraic derivative estimation with real time experiments

“…Finally, this methodology is well suited to confronting important problems of control systems. Its versatility and ease of implementation make the controller suitable to be robustly applied in a wide range of real engineering applications such as the buoyancy control of a submerged platform [34], the control of stair-climbing mobility systems [35][36][37][38][39][40][41] or the control of electronic converters [42]. This will be the topic of our future publications.…”

Optimized obstacle avoidance trajectory generation for a reconfigurable staircase climbing wheelchair

“…The trajectory generation presented in [33] demonstrates that passenger comfort conditions and the verticality of the chair were obtained by moving only a subset of all the degrees of freedom available in the wheelchair (the remaining actuated degrees of freedom are kept constant), thereby decreasing the power consumption. When this trajectory generation is used in the staircase climbing/descent process, we observe that the center of mass position of the wheelchair prototype remains constant throughout the configuration changes.…”

“…which are presented in order of calculation (see [33]). Similarly, if we assume that the chair frame does not rotate and that the angle of the slope trajectory has the same value as the angle of the terrain slope at the front axle, we obtain:…”

Application of Parallel Mechanism in Varistructured Quadruped/Biped Human- carrying Walking Chair Robot

“…The existing wheeled robots are capable of moving in structured and unstructured environments, going up and down stairs and climbing over obstacles [1,2] . However, compared with the legged human-carrying walking chair robots, the requirements for the wheeled robots on road surface are strict [3] .…”