Automatic heart-rate-based selection of pedal load and control system for electric cart

This paper describes an autoselection method for the pedal load of an electric cart, and the control system. The method checks the driver’s physical condition just before the start of driving, calculates the driver’s rating of perceived exertion, and uses that to automatically select a suitable pedal load. To ensure that the level of physical exertion is safe, the largest pedal load is determined on the basis of Borg’s CR10, the Karvonen formula, a pedaling experiment, and statistical data. A driver’s degree of fatigue is estimated from his heart rate, and a pedal load (between the largest and almost zero) is automatically selected. In addition, a dynamic output-feedback cart control system was designed that guarantees the stability of the cart system for any allowable pedal load. A stability condition is derived by employing the concept of dynamic parallel distributed compensation. Finally, experiments demonstrate the validity of the method.