Development of EDM Simulator

本研究旨在发展一种电火花成形模拟方法，以解决获得合适的工具电极形状以获得所需的最终工件形状的逆问题。在所开发的反向模拟方法中，采用了与正向模拟相同的算法。然而，工件在与正向模拟相反的方向上朝向工具电极进给，并且每次脉冲放电从工具电极和工件表面去除的层的深度的值与正向模拟相反。该算法是一个简单的重复过程，包括：1）确定下一个放电位置，2）删除工具和工件电极，3）分配碎片颗粒，4）进给工具电极。仿真包括分析金属丝的振动和寻找放电位置。结果表明，用概率法确定放电位置比用确定性方法确定放电位置更合理、更符合实际。仿真得到的加工形状与实际加工结果基本一致。研究还发现，自适应伺服进给控制容易导致在加工表面上产生条纹，而恒定进给速度控制没有这样的趋势。

This research aimed to develop a simulation method for die-sinking EDM to solve the inverse problem of obtaining the appropriate tool electrode shape for achieving the desired final workpiece shape. In the reverse simulation method developed, the same algorithm as that used in forward simulation is adopted. The workpiece is however fed towards the tool electrode in the direction opposite to forward simulation, and the values for the depth of the layers removed from the tool electrode and workpiece surface per pulse discharge are the reverse of forward simulation. The algorithm is a simple repetition of the procedure comprised of : 1) determining the next discharge location, 2) removing the tool and workpiece electrodes, 3) distributing the debris particles, and 4) feeding the tool electrode.This research also developed a WEDM simulation method. The simulation consists of the analysis of the wire vibration and search for discharge locations. It was found that using the probability method to determine discharge locations is more reasonable and realistic than using the deterministic method. The machined shape obtained from the simulation was consistent with those obtained from actual machinning. It was also found that adaptive servo feed control easily results in the generation of streaks over the machined surface while constant feed rate control has no such tendency.