Meiners, C., Zhu, W., and Ke, Y., "Innovative Approach to Circumferential Splicing for Large Aircraft Assembly," SAE Technical Paper 2015-01-2504, 2015, doi:10.4271/2015-01-2504.
The joining and assembly of barrel sections of large aircraft is always cumbersome. Any means to ease this task are welcome. In recent years The Boeing Co. has invented and licensed their “Flex-Track” system. But however flexible this approach may be, double curved surfaces, large variations of cross-section radius and issues with vacuum cup fixture are problems to be dealt with.Zhejiang University in Hangzhou, China has developed a new, innovative circumferential splicing system in cooperation with Broetje-Automation, Germany.There is a unique, time-saving setup technology and self-stepping actuation for a one up 360° splicing operation. The process endeffector is based on standard, state of the art components in use for large fastening systems. Features are high speed servo drilling spindle with HSK 32 drill chuck holder, tool changer, vacuum chip removal, reference hole detection and correction, surface normality alignment, pressure foot clamp-up, countersink control.An area of roughly 1,5 square meters can be accessed without re-stepping. Deep stroke z-axis is included in the 5 DOF kinematics to allow large variation of cross-section diameters. The dual track system locks itself to the barrel surface and totally avoids the use of vacuum cups. For this innovative approach target application is the fuselage barrel assembly of China's new transport aircraft.