An induction planar actuator for surface inspection

Planar motion over a surface is commonly acquired using a combination of rotatory motors and appropriate mechanical transmissions to convert the torque produced by the motor into linear motion. Typically, the assembly employs two motors: one is responsible for the motion in the x-axis and the other, for the y-axis [1]. A planar actuator achieves this kind of motion from only one device. Several different types of planar actuator have been studied. These have utilized different types of actuator, such as switched reluctance actuators [2], permanent magnet DC devices [3, 4, 5], and AC actuators [1, 6]. There are various possible applications for planar motion devices. There have been identified as being in the semiconductor industry (for wafer probers [2], extreme-UV lithography equipment [3], printed circuit board movers [4, 5], and scanning microscopy [5]) and for mobile robots [6]. Another proposed application is to use the characteristics of this new actuator for the inspection of inclined surfaces, such as ship hulls and oil tanks. Based on the adhesive nature of these devices, they can be classified into magnetic, vacuum or suction, grasping grippers, electrostatic and biologically inspired robots [7].