A novel method of surface-normal measurement in robotic drilling for aircraft fuselage using three laser range sensors

Surface-normal measurement is an essential part in robotic drilling system. A novel method to measure the surface-normal of aircraft skin is proposed in this paper. Resumptively, three laser range sensors evenly distributed around the drill bit are used to measure the distance from them to aircraft skin within a small area. So the coordinates of three measured points can be obtained, and the normal vector is calculated from the cross product of any two vectors that are tangent to the surface at the drilling point. The simulation results and experiment conducted on an aeronautical drilling robot validate the precision and efficiency improvement of the drilling. The presented method is appropriate for intelligent robotic drilling for aircraft fuselage.