Design Of Flexible Fixture Platform And Development Of The Control System

The flexible fixture has been applied in many areas because it can adapt to the workpiece shape and size change, such as aircraft integral structure parts manufacturing, and air surface parts manufacturing, aircraft assembly. Due to the use of flexible fixture, greatly reducing the manufacturing cost and improves the production efficiency. In this paper, the design method of flexible clamping platform is studied, and the control system is developed.In this paper, considering the actual demand of the manufacturing process, the flexible fixture system can be designed for workpiece with different sizes and different characteristics. The system provides a series of general or special function modules, which can be used to build the most suitable for the workpiece manufacturing. Considering the coordination between the system and the numerical control machine, it is needed to realize the communication with the numerical control system. This paper summarizes three methods of communication with SIEMENS 840 D, and develops the communication software based on OPC technology, and realizes the communication between the software and 840 D. At the same time, this paper studies the control system of the engineering equipment, and establishes the control system based on CAN bus. For upper machine and the lower machines to perform their duties in the CAN network, according to the requirement of system security, stability and extensibility, the command identifiers in the CAN network are assigned to ensure the stable operation of the system.In this paper, the flexible fixture is reconstructed for thin-walled box and surface structure, and the key technologies of reconstruction are studied. For the thin-walled box structure, it illustrates the necessity of dynamic support technology through the finite element simulation and verifies the feasibility of the method by analyzing the deformation of the support module, the deformation of the workpiece, followup support path and workpiece with dynamic support system modal. For thin walled curved surface structures, it solves point location determination, fixture layout and the design of clamping force before the reconstruction of fixture, and completes the reconstruction of fixture. Finally, for thin walled curved surface, the fixture layout optimization algorithm based on finite element method is proposed considering the convergence rate and improved the support stiffness, thus reduced the machining deformation.