Simplified prototype expert system to generate some modified paths

A new wheelchair system was fitted between the existing joystick and the wheelchair controller of a powered wheelchair as shown and described in Stott(2000). The new prototype systems were programmed to read the sensor systems and the joystick and to modify the joystick signals fed to the controller if required. New algorithms created during this work were used to modify the signals. The new algorithms recognised situations where the user may have needed assistance in steering the wheelchair. Expert systems were used to identify potential hazardous situations and to recommend safe courses of action. The micro-controller code was written as a series of modules, which were then integrated into the main micro-controller program. As each module was created it was tested and debugged before it was added to the system. Conflicts and timing issues were tested, detected and removed as the system code was integrated. This approach allowed problems to be identified and rectified early and before they became too embedded in the new system and made their detection difficult.