Movement of a Cableless In-Piping Magnetic Actuator With a New Propulsion Module

Abstract

It is important to inspect pipes used in nuclear power plants and reactors. A number of studies have investigated various locomotion mechanisms of robots controlled by electric cables in pipes. A cableless actuator capable of movement in narrow pipes of less than 15 mm has not yet been developed. The present paper proposes a novel cableless magnetic actuator with a propulsion module that exhibits a high thrusting force. The effect of the magnetic forces generated by two different propulsion modules on the movement of the cableless actuator was investigated theoretically and experimentally. The proposed actuator includes an electrical inverter that directly transforms DC from button batteries into AC. Experimental results indicate that the proposed actuator can move vertically at a speed of 225 mm/s, using the power provided by 10 button batteries when pulling no load mass. This cableless magnetic actuator has several possible applications, including inspection of small pipes.Index Terms-Cableless magnetic actuator, magnetic force, pipe inside mover, propulsion module, vibration.

Effect of Battery on Moving Properties of Cableless In-Piping Magnetic Actuator

“…The present study is to completely investigate the moving characteristics of the cableless magnetic actuator presented in the previous paper [16][17][18]. The effect of the two kinds of batteries on the moving properties of the cableless actuator was discussed.…”

“…A number of studies have investigated the mechanisms of an actuator controlled through an electric cable to provide locomotion in a pipe using devices such as piezoelectric elements [1,2], shape memory alloys [3,4], and electromagnetic motors [5][6][7][8][9][10]. However, little research has been conducted on cableless robots [11][12][13][14] and electromagnetic vibration type [15][16][17][18] proposed by authors. In the case of cableless robots, cableless actuators are not capable of movement over long distances.…”

“…The authors previously proposed [16][17][18] a novel cableless actuator that provides propulsion by a new motion principle that combines mechanical vibration and electromagnetic force. However, the moving properties by effect of loaded battery are not completely investigated.…”

Cableless In-piping Magnetic Actuator for Transportation over Long-range

“…There are several potential problems in the design, however, with regard to extending the range and avoiding tangling of the electrical cable, and thus it is clearly desirable to adopt a cable-free system. However, little research has been conducted on cableless robots (Fukuda et al, 1991;Tsuruta et al, 2002) and electromagnetic vibration type (Yaguchi et al, 2009;Yaguchi et al, 2011;Izumikawa et al, 2012) proposed by authors. Experiment results were compared to analytical results and the validity of the novel motion principle was completely verified (Yaguchi et al, 2013).…”

“…The actuator which contains ten batteries has a length of 80 mm and a total mass M a of 12 g. The magnetic actuator is able to move by the difference in frictional force between forward and backward supporting force of the natural rubber Yaguchi et al (2013). Figure 2(a) illustrates the principle of the electrical DC-AC inverter proposed in the previous paper (Yaguchi et al, 2011;Izumikawa et al, 2012;Yaguchi et al, 2013), which was developed in order to realize a cableless magnetic actuator. Figure 2(b) illustrates the principle of the proposed electrical DC-AC inverter.…”