A Novel Cableless Magnetic Actuator Capable of Reversible Motion in a Thin Pipe

This paper proposes a new type of a cableless magnetic 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 a pipe. This actuator contains a mechanical inverter that directly transforms dc from button batteries into ac. The mechanical dc-ac inverter incorporates a mass-spring system and a curved beam with a concentrated mass that switches under an electromagnetic force. The actuator is moved by inertia force of the mass-spring system due to mechanical resonance energy. Experimental result shows that the actuator is able to move upward 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 actuator capable of moving in pipes with diameters of under 8 mm.