Disclosed is a mechanical actuator system for generating a force needed for actuating an actuating member of an EOAT device as required. The actuator system has at least one functional unit which is designed to change the dimension of the functional unit reversibly in a preferred direction (R) of the functional unit when energy is supplied. The invention further relates to an EOAT device, in particular in the form of a gripper or of a cutting tool, having at least one actuating member and an actuator system associated with the at least one actuating member.