【摘要】 机床的各种误差是影响机床加工精度的重要因素，其中机床几何误差是主要的误差来源之一。为消除机床几何误差对加工精度的影响，以球头刀三坐标数控(numerical control,NC)铣削加工为研究背景，基于齐次坐标变换理论与刚体运动学方法，结合机床运动链拓扑结构分析，将机床几何误差映射到球头刀刀心的位置误差上。根据球头刀铣削工件表面成形原理，考虑机床几何误差与球头刀刀心位置间的映射关系，构建出刀心曲面与工件表面/设计曲面之间的正逆向计算模型。通过该模型求解出消除机床几何误差的编程刀心曲面，将该曲面导入CAM软件，即可获得消除机床几何误差的NC加工程序。通过曲面实例进行计算和仿真，佐证了该方法的可行性。更多还原

【Abstract】 The important factors affecting the machining accuracy of machine tools are various errors of machine tools,among which the geometric error of machine tools is one of the main error sources.In order to eliminate the influence of geometric errors of machine tools on machining accuracy,the homogeneous coordinate transformation theory,rigid body kinematics method and topological structure analysis of machine tool kinematic chain are used to map the geometric errors of machine tools to the position errors of the ball head cutter center,taking the ball-end cutter three-coordinates NC milling as the research background.Based on the principle of forming the surface of a workpiece by milling with a ballend cutter,a forward and reverse calculation model between the tool centre curved surfaces and the workpiece surface/design surface is constructed,taking into account the mapping between the geometric error of the machine tools and the tool centre position.The model is used to solve for a programmed tool centre curved surfaces that eliminates machine geometric errors,which is then imported into CAM software to obtain an NC machining program that eliminates machine geometric errors.The feasibility of the method is verified by the calculation and simulation of surface examples.更多还原