High-Accuracy Robotic Drilling/Milling of 737 Inboard Flaps

The processes of drilling and milling Boeing 737 inboard flaps at Triumph Aerostructures have been enhanced by an accurate articulated robotic system. Tool point positioning is handled by an off-the-shelf 6-axis KUKA KR360 robot riding on a linear axis. Each of the 7 axes is enhanced with secondary position encoders. A single process head performs all required functions, including one-sided pressure application, touch probing, barcode scanning, drilling/countersinking, measurement of hole diameter and countersink depth, and face milling. The system is controlled by a Siemens 840Dsl CNC which handles all process functions, robot motion, and executes software technologies developed for superior positional accuracy including enhanced kinematics, automated normality correction, and anti-skid correction. The layout of the assembly cell allows the robot to span four fixture zones. Part programs are generated offline in the Catia environment using an offline programming and simulation package.