Integrated phases modular fuzzy logic control with spiral dynamic optimization for stair descending in a wheelchair

This paper presents a modular fuzzy logic control structure with spiral dynamic algorithms (SDAs) and their application in controlling a stair climbing wheelchair specifically in descending task. To ensure smooth and stable stair descending operation using a wheelchair without collapsing or slipping is a very challenging problem. Suitable design and control strategies need to be adopted to achieve the goal. The wheelchair system is developed using link/cluster rotation mechanism within a CAD software called Visual Nastran 4D (VN4D) and integrated with MATLAB for the ascending and descending motion control. A new spiral dynamics algorithm based fuzzy logic control is used to optimize the control parameters to improve its performance in terms of seat/tilt angle and wheels position. A comparison of heuristic (trial and error) method and SDA approach is presented in assessing the performance of the wheelchair in stair climbing operation.