The Development Of WXJJ-BZJ-02 Micro Parts Assembly Equipment

With the continuous development of modern manufacturing technology,devices and products are continuously miniaturized,and the assembly requirements of millimeter scale and micron precision are increasing in the manufacturing process.The performance and batch requirements of precision micro-devices such as accelerometers used in aviation,aerospace,and other fields are constantly improving.Traditional manual and semi-automated assembly methods are no longer sufficient for production needs,therefore,improving the automation of assembly and developing an efficient,stable and reliable fully automatic micro-assembly system has become an important way to improve product quality and meet the needs of mass production.This paper studies the fully automatic assembly technology of micro-accuracy accelerometer components.This research includes the precise operation of multiple small parts in the assembly,the automatic locking during the assembly process,the automatic loading of the parts before assembly and the automatic unloading after the assembly is completed.The structure of the WXJJ-BZJ-02 micro-assembly system equipment was designed,the control software of the assembly equipment was developed,the assembly equipment was calibrated,and the assembly experiment was carried out.The WXJJ-BZJ-02 automatic precision assembly system consists of five modules: automatic loading and unloading module,vision module,assembly operation module,work table module and loading platform module.The automatic loading and unloading module is used to realize the interaction with the material of the production line,which ensures the continuity of the assembly process and realizes the full automation of the assembly.The loading platform module provides a fixed platform for the parts before assembly.The vision module is used to monitor the assembly process while acquiring part images to aid in assembly tasks.The assembly operation module is used to realize the stable picking and releasing function for small parts.An integrated clamp is designed,and the operation of different small parts is realized by vacuum adsorption,and the micro force sensor is embedded on the mechanical arm unit.Real-time control of the assembly force of the assembly process is realized,and the micro-parts are effectively prevented from being damaged due to excessive force.The assembly platform module provides working space for parts assembly.For the requirement of locking and fixing after the assembly of small parts,an automatic locking fixture is developed independently,which can realize automatic locking of small parts and avoid manual intervention.Based on the modular idea,a layered software framework is designed,which divides the assembly software into interaction layer,task layer,logic layer and behavior layer.The interaction layer is mainly used to display the assembly process information while allowing input of instructions.The task layer divides the assembly process and sends the task to the logical layer in the form of a message.The logic layer is mainly responsible for receiving the message after the task layer is decomposed,and sending the assembly message for the hardware to the behavior layer,and also receiving the information fed back by the behavior layer.The behavior layer is the program layer that directly controls the hardware.Each layer performs its own tasks,and the layers communicate with each other through interfaces.The upper layer controls the lower layer through the interface,and the lower layer feeds information back to the upper layer through the interface.According to the assembly precision requirements and assembly sequence of parts,the assembly process was designed,and the subdivision of assembly tasks was realized.Finally,the control software was written according to the control software framework and assembly process.Finally,the error caused by the system hardware installation is analyzed,including the installation error of the visual measuring device and the installation error of the moving parts of each module.Based on the system hardware,the error compensation model is established,and the calibration error is compensated by the calibration experiment,which improves the assembly precision of the system.The assembly experiment was carried out,and the results show that the system can achieve the assembly task with predetermined precision.