Assembly 4.0 - Flexibly Picked Up, Precisely Mounted

Abstract

C omponent deviations between as-designed and as-built as a result of deformations in the production process lead to significant cost increasing during assembly. After quality inspection, components are provisionally preassembled to determine their matching accuracy. Components with an acceptable tolerance range are then assembled. Otherwise costly reworks are required. Subsequently, the preassembly process is repeated until acceptable assembly tolerances are achieved. To avoid this time-consuming and costly process loop, a flexible mounting frame coupled with a real-time measuring system is used to optimize the assembly process. The flexible mounting frame can be applied for many applications where components are to be aligned and mounted. This flexible mounting frame allows the realization of exact shape and acceptable position tolerances. The mounting frame consists of telescopic carbon fiber reinforced polymer (CFRP) tubes, linear actuators and suctions grippers. Linear actuators deform the component in the elastic range. Connected vacuum suction grippers hold the component securely to the mounting frame. The individually configurable joining device compensates manufacturing deviations during assembly in the elastic range. This is realized through a real time 3-D surface measuring system that assists in controlling a variable number of actuators. The geometric deviations are detected contactless by an external measuring system. This system provides the required measurements to control the actuators. By decoupling the measuring method from the manipulator, the system design can be kept very simple without compromising accuracy. Furthermore, the frame is mounted on a mobile robot platform. The applied mobile robot platform consists of the mobile platform (KUKA omniMove) and an industrial robot (KR QUANTEC 150 R3300 prime K). By using such mobile robot, the system can be universally used. Moreover, components can be brought into the assembly position by contour optimized elastic deformation. This novel implementation of flexibly pick up and precisely mounting system results in a more efficient and faster assembly. FIGURE 1 Assembly process for an aircraft wing made of fiber-reinforced plastics.

Assembly of Compliant Structures with Autonomous Industrial Mobile Manipulators (AIMM) Using an End Effector with Active Deformation Compensation for the Assembly of Flaps

“…His results show that 3D cameras are able to generate very detailed information regarding the shape and shape deviation from the target shape. The large residual shape deviation after nine iterations of shape measurement and active deformation suggests either a too low stiffness of the main frame, too low actuation forces or stroke or not enough control ability of the shape due to the configuration of the linear actuators [8].…”