Range estimation system for powered wheelchairs

In this paper, we present a method to estimate a wheelchair's power consumption and therefore its battery autonomy. The wheelchair powertrain is modeled to enable a virtual driving simulation. The use of a white box model enables an adaption to other systems and configurations. This model outputs the actual battery and motor currents within a simulation for a given route and speed profile. These currents affect the battery's SoC, whose total charge depends on its temperature. To account changes of the available charge, a simplistic model of the battery's temperature dependence is introduced, that has been acquired via discharge cycles within a climate chamber. Furthermore, an a priori simulation uses the model to estimate the SoC after the virtual completion of a route with a corresponding height and velocity profile. Finally, the paper compares the results of the simulation with real measurements using the recorded tracks and the generated virtual routes. Since the input for the a priori estimation relies on virtual routes, their quality is assessed as well.