Analysis of a Vehicle Propulsion System Using Continuous Track LIMs on Steel Plates

A robotic vehicle based on a novel Linear Induction Motor (LIM) has been developed for operation on steel, iron or other surfaces with high magnetic. A control strategy that utilises the coupled nature of the attractive normal and linear thrust forces has been developed that focuses on achieving adhesion to a non-horizontal surface as well as peak thrust for given structural and operational parameters. The developed vehicle has a total mass of 28kg and has been experimentally tested to develop a peak thrust force from standstill of 90N for an input power of 1.7kW by switching 220V supply at 10-20Hz. Analysis shows that the vehicle generates the greatest force with a slip frequency between 10–20 Hz, that the greatest normal force of 518N at 5Hz was developed when climbing at 121°, and 11W is lost in the reaction plate through 3A/mm2 eddy currents. The magnetic field Z-component is shown to be quasi-sinusoidal, and an attractive force of 714N is generated.