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A design of aircraft drilling end-effector based on flexible railway

This paper describe a design of aircraft drilling end-effector (ADEE) based on flexible railway which is mainly used for drilling on the surface of fuselage and wing of aircraft. The whole system is composed of several different modules. Flexible railway module (FRM) make ADEE move to any places where need to be drilled. Framework and Z axis module (FZM) uses high-rigidity framework and linear slide guide to guarantee the precision and stability of the drilling action. Compression and absorbing chipping module (CACM) adopts symmetric double-cylinder structure and generates 1000N compressing forces that can compress three layers aircraft skin and is increased by demand. Vacuous absorbing chipping mechanism uses high flow vacuum generator as vacuum air source and filters metal shavings by filter. Visual inspection module (VIM) can precisely calculate the distance between three points around drill bit and finished surface by calculating, and then achieves verticality deviation value through normal detection algorithm. Binary angular adjustment module (BAAM) revises angle deviation that is caused by the differences of adsorption position diameter of two rows of rack. ADEE is more flexible and better adaptable; meanwhile, it can greatly improve the efficiency and precision of the holes. It does not use drilling fluids in the whole manufacturing process and fundamentally eliminates the pollution problem of the drilling fluid. In conclusion, experiments show that ADEE can meet the requirements of automatic drilling of departments of aircraft and greatly enhance the quality and speed of drilling holes.