This paper describes the development of a novel multi-wheel stair-climbing wheelchair. The necessity for mobility aid technology for elderly and handicapped people that has “minimal invasiveness for use in an historical environment” is described. With this goal in mind, a prototype of a novel wheelchair having a stair-climbing function resulting from transformable wheeled four-bar linkages is proposed. The mechanical design, principle of operation and statics of the proposed mechanism are thoroughly illustrated. The basic performance of the proposed mechanism has been confirmed through experimental results.

A novel stair-climbing wheelchair with transformable wheeled four-bar linkages

As an autonomic and convenient assistance device for people with disabilities and the elderly climbing up and down stairs, electric-powered wheelchairs with stair-climbing ability have attracted gr...

https://journals.sagepub.com/doi/pdf/10.1177/1729881417721436

Electric-powered wheelchair with stair-climbing ability

This paper describes a novel stair-climbing wheelchair operated by human upper body using lever propelled rotary-legs with posture transition mechanism. The design principle of this wheelchair is t...

Stair-climbing wheelchair with lever propulsion control of rotary legs

For the attitude control of a novel stair-climbing wheelchair with inertial uncertainties and external disturbance torques, a new synchronous control method is proposed via combing high-order sliding mode control techniques with cross-coupling techniques. For this purpose, a proper controller is designed, which can improve the performance of the system under conditions of uncertainties and torque perturbations and also can guarantee the synchronization of the system. Firstly, a robust high-order sliding mode control law is designed to track the desired position trajectories effectively. Secondly, considering the coordination of the multiple joints, a high-order sliding mode synchronization controller is designed to reduce the synchronization errors and tracking errors based on the controller designed previously. Stability of the closed-loop system is proved by Lyapunov theory. The simulation is performed by MATLAB to verify the effectiveness of the proposed controller. By comparing the simulation results of two controllers, it is obvious that the proposed scheme has better performance and stronger robustness.

/pdf/high-order-sliding-mode-based-synchronous-control-of-a-novel-2jkix5caf2.pdf

High-order sliding mode-based synchronous control of a novel stair-climbing wheelchair robot

This paper presents a novel stair recognition method by utilizing three-dimensional (3D) scanning for a hexapod robot to climb stairs. The method is based on the premise that stairs are composed of several parallel planar surfaces. A 3D laser range finder (LRF) system equipped on a hexapod robot is developed for performing 3D scanning. The algorithm can be divided into two procedures. At first, detecting the edge points of stair tread surfaces is performed in 2D range images. In order to enhance the robustness of the method and extract the edges more accurately, edge point searching is executed between neighbouring scan planes. Next, the extraction of the tread surfaces is carried out by using these detected edge points in 3D space. The performance of the proposed method is investigated through various experiments. As the experimental results demonstrate, the method is sufficient accurate to detect the tread surfaces and useful for a hexapod robot to climb the stair.

A method to detect stairs with three-dimensional scanning for hexapod robot stair climbing

This paper proposes a control algorithm for continuous high-speed stair climbing for an eight-legged stair-climbing vehicle, and discusses a new leg mechanism to implement this control. The control algorithm was first simulated to verify its effectiveness, and then implemented with a vehicle prototype, which continuously climbed a set of steps at constant speed under an applied load of 30 kg. A belt-drive mechanism with a long leg-stroke was developed, along with a mechanism to control the orientation of the passive wheels; both were experimentally verified. The success of these experiments indicates that the new control algorithm and leg mechanism are promising components for practical stair-climbing applications in the future.

Daniel Davies

Papers

Continuous high-speed climbing control and leg mechanism for an eight-legged stair-climbing vehicle