People withmultiplephysicalandcognitiveimpairmentshavedifficultiesforusingproperlyconventional pointingdevices,what reduces their possibilities to communicate and improve their cognitive and physical skills through computers. This paper proposes a head control mouse based on a triaxial inertial sensor particularly focused on infant swith cerebral palsy(CP).The system consists of a real-timehead tracker that translates the head orientation into pointer positions and measures kinematic parameters through the 3D inertial sensor.The algorithm to estimate the angular head orientation is presented and validated with an accuracy about 1◦. The experimental results with five healthy users demonstrated that the inertial pointer succeeds what was validated according to the ISO924
Part9.The experimental results with two infant swith CP(a the toid and dystoniccases) demonstrated that the infants are capable of placing the pointer around the target but they have difficulties for fine motor control.The inertial sensor offers interesting kinematic parameters of the pathological movement.The separameters can be directlyobtained by the inertial signals and are very useful to design filter ingtechniques to extract voluntary intentions.