Design and testing of low cost three-modes of operation voice controller for wheelchairs and rehabilitation robotics

People who have lost their walking and moving ability need to use a wheelchair. In cases of losing complete control of the upper and lower limbs, intelligent solutions are required to ensure the autonomy and independence of those patients. The intelligent application must be designed carefully to use the available self-controlled electrical and physical activity of the patient´s body like sound, Electromyogram (EMG), Electrooculogram (EOG) and body movement as an input control signal. In this paper, we describe the design and implementation of three modes of operation for a voice controller: the sound dependent (SD) mode with dynamic time warping algorithm (DTW), the sound dependent (SD) mode with Hidden Markov Model algorithm (HMM) and the sound independent mode (SI) with text to sound independent algorithm (T2SI). The user voice command will be processed in parallel by the voice recognition (VR) algorithms and the output of the VR will be fed to the microcontroller unit (μC), which is responsible for controlling the movement and direction of the wheelchair or the rehabilitation robot.