A New Type of Magnetic Actuator Capable of Wall-Climbing Movement Using Inertia Force

This paper proposes a new type of a magnetic actuator that operates on a resonance energy of a mass-spring model by using an electromagnetic force. The magnetic actuator is moved by the difference in an inertia force during one period of vibration. Experimental result demonstrates that a horizontal speed of the magnetic actuator was 7.4？mm/s with load mass of 50？g. We considered a method of a cable-free movement of the actuator by using two iron rails and four permanent magnets. The magnetic actuator is able to move stably a ceiling plane and a wall plane. This actuator is able to move on the plane of the magnetic materials only a function generator and a power amplifier. 1. Introduction Under the field and the environmental situation that a human being cannot inspect directly, a robot capable of actual work and inspection is desired at the field of each industry. In a large tank and bridge, periodical inspection is required. In the building, the inspection of the outer wall and the actual work of the wall surface are required. As an adsorption method for wall surface movement, a method using magnetic attractive force [1–3] and the method to produce negative pressure [4] by using the devices such as a sucker or the pump, the method using van der Waals forces [5], a technique using the adhesive elastomer [6], and the method of magnetic wheel [7] were suggested, and the establishment for principle of locomotion has been accomplished. However, at the mobile robot as mentioned above, the moving speed is low by problem of controllability and own weight. The development of a superior actuator of lightweight and operability is very important. We demonstrated a cable-free microactuator [8, 9] of vibration type by using an inertia force. In this previous paper, examination of cable-free and downsizing of the actuator were mainly considered. The moving properties of the actuator are not examined. In this paper, we again propose a new type of a magnetic actuator capable of movement on a magnetic substance such as an iron rail using an inertial force of a mass-spring model. A prototype actuator was fabricated, and it is able to move on the magnetic substance. Experimental result shows that a horizontal speed of the actuator was 7.4？mm/s with load mass of 50？g. In addition, we considered a method of a cable-free movement for the actuator by four permanent magnets and using two iron rails. It was confirmed that this actuator is able to move on the plane of the magnetic materials only a function generator and a power amplifier. 2. Structure of the Magnetic Actuator by