论文标题
水平集拓扑优化的减法制造约束
A subtractive manufacturing constraint for level set topology optimization
论文作者
论文摘要
我们提出了一种在生成的零件中执行生产性约束的方法，以便使用减法方法自动准备制造。我们主要针对多轴CNC铣削方法，但该方法也应推广到其他减法方法。为此，我们将其作为用户输入：工具位的曲率半径，工具头的粗糙模型以及一组铣削方向。这使我们能够执行以下可制造性条件：1）表面光滑度使得零件的曲率半径不会超过铣削位半径，2）方向使得要铣削的每个部分都可以从至少一个铣削方向上可见，3）可访问性可以通过工具在无需处理工具或螺距安装的工具的情况下到达每个表面。我们将展示如何在基于级别的拓扑优化中有效地强制执行约束，以修改对流速度，以便在每次迭代中，拓扑优化保持下降优化方向，并且不会违反任何可制造性条件。该方法通过在每次迭代时可以访问机器可以访问的材料来对实际的减法过程进行建模，直到实现本地最佳。
We present a method for enforcing manufacturability constraints in generated parts such that they will be automatically ready for fabrication using a subtractive approach. We primarily target multi-axis CNC milling approaches but the method should generalize to other subtractive methods as well. To this end, we take as user input: the radius of curvature of the tool bit, a coarse model of the tool head and optionally a set of milling directions. This allows us to enforce the following manufacturability conditions: 1) surface smoothness such that the radius of curvature of the part does not exceed the milling bit radius, 2) orientation such that every part of the surface to be milled is visible from at least one milling direction, 3) accessibility such that every surface patch can be reached by the tool bit without interference with the tool or head mount. We will show how to efficiently enforce the constraint during level set-based topology optimization modifying the advection velocity such that at each iteration the topology optimization maintains a descent optimization direction and does not violate any of the manufacturability conditions. This approach models the actual subtractive process by carving away material accessible to the machine at each iteration until a local optimum is achieved.
