Fuzzy Logic for the Control of Advanced Mobility Support Devices

Robert Prinz

Fuzzy logic extends conventional logic and set theory to include the idea of partial truth and partial set membership. Originally introduced as a means of modelling natural language, the most successful application of fuzzy logic has been the fuzzy logic controller. Used in the control of autofocus in digital cameras, heat chambers, washing machines, elevators, etc., fuzzy logic has become a simple and increasingly prevalent form of artificial intelligence in our daily lives (even though most of us are not aware of it). In my master’s thesis I used fuzzy logic as a means of artificially reproducing the human movement — sit-to-stand. Sit-to-stand is simply the movement from a sitting to standing position. The idea is to use a fuzzy logic controller to control the activities of an advanced mobility support device, such as a powered orthosis or exoskeleton, which provides active mobility assistance to the user. This work was presented at the 33rd Canadian Medical and Biological Engineering Conference recently held in Vancouver.