The magnetic field analysis and optimization of permanent-magnetic adhesion device for a novel wall-climbing robot

The climbing-wall robot based on permanent-magnet adsorption is always concentrated on tracked-type, but robot with this type is deficient flexibility when it moves. In this paper, a new permanent-magnet adhesion device of an adjustable pole is introduced in the wheel-type robot, the device can provide 1500N force when the air gap between the device and wall is 4mm to meet load requirement in working state, and at this time the magnetic flux leakage is very small. While permanent magnetic force is almost approach zero when device in non-operating state, so the robot can up and down the wall conveniently. The mathematic model is established by Finite Element Method to calculate and design magnetic field. The finite element software is used to analyze and optimize the magnetic field distribution, magnetic field intensity as well as the structure size which will affect magnetic field intensity to the device. Optimization results show that every parameter has a different influence on adsorbability of the device when it changes. Ratio between the maximum and minimum of adsorbability in two states is more than 5666 times when structure is designed reasonably.