Tolerance Adjusted Bonding of Large CFRP Structures:Automated Gap Analysis in an Offline ProgrammedRobot Assembly Cell

This paper presents a method to calculate the gap between joining partners for the automated application of adhesives. The new method used 3D measurement techniques to create a virtual setup of an assembly cell to simulate the entire joining process. This simulation was used to derive the resulting gaps between the joining partners and to calculate the right amount of adhesive on the joining surfaces. The new method was implemented in an automated robot assembly cell to join a large CRFP part into an aircraft shell. CFRP parts are used to build complex lightweight structures (e.g. fuselages, wings or tail planes) in the aircraft industry. These assemblies are made out of several hundred parts and therefore result in many contact points that need to be applied with adhesive or shim material. In order to assure a cost efficient and flexible setup all demonstrated processes were realized with standard industrial robots. The developed fully automated gap analysis calculated the needed adhesive at all contact points and the standard industrial robot applied the adhesive on the contact surfaces accordingly. This setup was evaluated by comparing measured and calculated gap values and demonstrated the efficiency of manufacturing strategies for future airplane generations.