An operating status of a motor in adrive unit is analyzed to extend the life ofthe motor. A wearable motion assistive device1 includes a shoulder joint mechanism 5 and anelbow joint mechanism 6 for aiding a movementof the shoulder joint and the elbow joint, anda control unit 100 having a control circuitfor controlling drive units 11 for theshoulder and elbow joint mechanisms 5 and 6.The control unit 100 controls the drive units11 based on a physical quantity and abiosignal detected by an angle sensor, atorque sensor, and a biosignal detectingsensor. A controller in the drive unit 11includes a motor monitoring unit formonitoring an operational status of the motor,and a motor control unit for limiting a drivesignal supplied to the motor based on amonitoring result provided by the motormonitoring unit, in order to prevent anoverload state of the motor.
