In five-axis machining, the setup of workpiece on the machine's table is an essential element of the kinematic chain that affects the performance of machine tools, such as the kinematic behavior and machining accessibility. In this paper, a mathematical model between singularity, a special kinematic behavior of five-axis machine tool, and the workpiece setup is built, and another model between accessibility of machine tool and the workpiece setup is presented. Regarding the above two models, a geometry-based approach is presented to unify and simplify them. By considering the two constraints of singularity-free and full accessibility, a general framework for the workpiece setup optimization of five-axis machining is established, from which the orientation and position of the workpiece on the table is optimized. To validate the advantage of the proposed framework, some physical cutting experiments and simulation are implemented toward a typical five-axis machine tool, testifying that the optimal setup can be achieved efficiently with the kinematic performance, surface machining quality as well as the machining efficiency significantly improved compared with the benchmark.

在五轴加工中，将工件放置在机床工作台上是运动学链中必不可少的要素，它影响机床的性能，例如运动学性能和可加工性。本文建立了奇异性，五轴机床的特殊运动行为与工件装设之间的数学模型，并提出了机床可及性与工件装设之间的另一个模型。关于以上两个模型，提出了一种基于几何的方法来统一和简化它们。通过考虑无奇点和完全可访问性这两个约束条件，建立了用于五轴加工的工件设置优化的通用框架，从中优化了工件在工作台上的方向和位置。