Improvement of moving characteristics of cableless micro-actuator and consideration of reversible motion

We previously proposed a novel cableless micro-actuator that provides propulsion using the mechanical resonance energy of a system excited by an electromagnetic force. However, it was possible for that the actuator to move only one direction and comparative low speed locomotion. This paper proposes a cableless micro-actuator that exhibits a high speed locomotion and considers reversible motion of the cableless actuator due to control of a magnetic field by using coils outside the pipe. This actuator contains a mechanical inverter that directly transforms DC from button batteries into AC. The mechanical DC-AC inverter incorporates a one-degree-of-freedom-model and a curved beam with a concentrated mass that switches under the electromagnetic force. The actuator is moved by inertia force of the one-degree-of-freedom-model due to mechanical resonance energy. Experimental results show that the actuator can move upwards at a speed of 16.5 mm/s by using 10 button batteries when pulling 10 g load mass. The results hold great promise for the creation of highly mobile actuators capable of moving in thin pipes with diameters of under 8 mm.