Design and Analysis of Lightweight Permanent Magnetic Wheels for Inspection Drone

General inspection task using a drone is limited to taking pictures while hovering in a distance from the target position. However, direct contact or approaching closer to the object is required for a more thorough investigation. For the realization of such a close distance inspection by a drone, especially to a magnetic object, two novel magnetically adhesive wheels are proposed in this research. Their magnetic force can be controlled by changing the direction of the included magnets. Thus, the force can be varied to make the drone fly or stick to the object being inspected. Unlike usual inspection by hovering, the drone with the proposed magnetic wheels does not require energy while adhering. Moreover, it is capable of moving on the surface of magnetic objects, which makes the drone to save more energy for its flight time. Two proposed design prototypes were examined through the adhesion experiment. Their adhesion forces were calculated by conducting an adhesion simulation under a variety of conditions. Finally, the validity of the prototypes was verified through comparisons between the simulation result and the actual adhesion force.