An alternative human inteface enabling people with severe motor disabilities to control ail assistive system is presented. Since this interface relies oil the biosignals originating from the contraction of muscles oil the face during particular movements, even individuals with a paralyzed limb can use it with ease. For real-world application, a dedicated hardware module employing a general-purpose digital signal processor was implemented and its validity tested on an electrically powered wheelchair Furthermore, ail additional attempt to reduce error rates to a minimum,for stable operation was also made based on the entropy information inherent in the signals during the classification phase. In the experiments, most of the five participating subjects could control the target system at their own will, and thus it is found that the proposed interface can be considered a potential alternative for the interaction of the severely disabled with electronic systems.