Perpendicularity adjustment end effector for aeronautical drilling robot

The quality of holes has important influence on the mechanical strength, assembly quality and life of aircraft, and inferior quality holes may even cause airplane crash and casualties. The perpendicular accuracy of holes during drilling is crucial one of all the factors influencing the quality of holes. In order to improve the perpendicular accuracy during drilling, this paper presented an attitude adjustment mechanism and attitude adjustment algorithm for the end effector. For the mechanism, it adjusts the drill bit attitude by using double eccentric discs and a spherical pair. After the surface normal vector at drilling point is obtained, double eccentric discs will rotate define angels calculated by using attitude adjustment algorithm based on the shortest time principle to achieve the coincidence of the surface normal vector and the drill bit axis vector if the angle between the normal vector and drill bit axis vector is greater than 0.5°. To demonstrate the method mentioned above, simulation and experiment are carried out on the aeronautical drilling robot. The results show that the attitude adjustment mechanism and attitude adjustment algorithm can increase the perpendicular accuracy of holes during drilling and satisfy the demand in automatic aircraft assembly.