The Research Of High Power LED Molding Motion Controller

In recent years, with the LED manufacturing process continues to progress and thedevelopment and application of new materials, LED luminous efficiency continues to increase,the cost of LED is gradually reduced, making the LED is widely used to the fields, such asindicate, display, decorative, backlighting, general lighting and urbannight scene of the fields.The LED light source has the advantages of energy saving, environmental protection, long life,small size etc, so it has been thought the fourth generation of light source after the fluorescentlight, and has great potential market.The packaging of LED industry plays an important role in the performance of LEDluminous. LED Molding machine is used to complete the lens molding process, compare tothe traditional PC lens+soft silicone perfusion, the LED Molding machine can improve theproblem of yellow fast, light-cost, low efficency and high defect rate.The main motion for LED Molding machine is continuous move on the filling plastictrack with high speed and least time. Under the full research of the motion controller structure,we design the motion controller architecture based on DSP+FPGA. The DSP is the centercontrol unit used to realize the motion control algorithms, task scheduling and system statusmonitoring; The FPGA is the execution units used to output the servo and IO.The LED Molding motion controller use the S curve acceleration and deceleration wayto achieve the smooth transition of the speed, this paper proposed the asymmetric Sacceleration and deceleration curves planning algorithm based on the acceleration time, thealgorithm can eliminate “tail problem” caused by time round and without the decelerationpoint forecast and real-time iterate the speed which can effectively reduce the computation.With the S acceleration and deceleration curves, we realize the line and circular interpolationbased on time segmentation, to avoid the accumulated error we adopt the absolute coordinateinterpolation.In the continuous path motion control, the traditional control method start and stopbetween each micro-segment, reducing the efficiency of processing. In this paper, based onthe analysis of the dynamics characteristics of the machine, we propose the arc transition onthe turning point and establish the velocity model of arc transition which can effective smoothand raise the turning point speed, the processing error can controlled by the transition speed.Then we combine pre-reading multi-track way and S acceleration and deceleration curveplanning which can improve the processing efficiency. Finally the motion control algorithm is verified by experiments.