Development Of Automatic Feeding And Unloading Manipulator For The Precious Metal Jewelry Processing

In the gold jewelry processing market, different with other countrie s’ manual processing, our country’s gold jewelry processing rely on mechanical production. On the one hand, traditional artificial feeding, makes the workers exposed to metal dust directly, lead to respiratory diseases and other legal disputes. On the other hand it also restrict the development of gold jewelry processing industry automation seriously. According to the above situation, this paper puts forward a set of automation feeding solution for jewelry processing industry.The main work of the project was divided into three parts. It includes mechanical system structure design, the design the robot control system and simulation research of the control algorithm. In this scenario the feeding manipulator, using Offset Slider-Crank Mechanism with Parallelogram Linkage design and optimize the structure size based on the Adams simulation technology, to ensure the stability of clamp workpiece. Besides instead of using AC servo motor and harmonic reducer that they are large and costly, we choose the stepper motor as the driving element. It makes cost greatly reduced, and the whole machine volume control in the 400 mm×400 mm×280 mm, making it possible to overall inline on the target machine. Besides, a lot of experiments for open loop contorl and closed loop control have been made in order to avoid the loss step unstabble situation. The experiment result shows that the accuracy of the planar position and manipulator can reach 0.5 mm. And the upper software provides real-time display and real-time control of the manipulators coordinates. In addition, basised on the mathematical model of stepper motor and combining the specific operating conditions in the project, we designed increamental PID algorithm to control step motor for improve system stability. Besides we applied the Simulink simulator tool of MATLAB software, adaptive fuzzy control system was established, which serves as a control theory for the following research.Finally, the feeding manipulator completed clamping, positioning and spinning with stable and accurate. In subsequent experiments we planed the manipulator’s trajectory planning, matched with the movement of CNC machine, achieving feeding and unloading automatically.