Cutter radius compensation （CRC） is a very important function of numerical control（NC） system. We refer to a large number of NC information and sum up the CRC function. We illustrate how to realize rough machining...Cutter radius compensation （CRC） is a very important function of numerical control（NC） system. We refer to a large number of NC information and sum up the CRC function. We illustrate how to realize rough machining ＆ finish machining by the same program, machining matching surface by the same program, simplify pro- gramming methods, realize direct programming by parts contour, remove machining allowance by the increase of CRC value, control the parts size precision by adjusting the CRC value, state the essence of the CRC, and elucidate the physical meaning of the CRC value.展开更多
When the five-axis CNC system executes the 3D cutter radius compensation function,the angle between two adjacent radius compensation vectors might become very large and the linear axes would move too fast if the tool ...When the five-axis CNC system executes the 3D cutter radius compensation function,the angle between two adjacent radius compensation vectors might become very large and the linear axes would move too fast if the tool orientation vector is close to the surface normal.The reason that results in this phenomenon is analyzed based on building the transmission relationship between the cutter contact point and the cutter location point.By taking the square-end tool as an example,an optimization algorithm to control the undesired movements is advanced.For the singular area where sudden change exists,the number of interpolation cycles is determined by the cutter feedrate,the limit speeds of machine axes and the maximum allowable angle between radius compensation vectors of adjacent NC blocks.The radius compensation vector of each interpolation cycle is obtained by a kind of vector rotation method.By maintaining the perpendicularity between the radius compensation vector and the tool orientation vector,the rapid movements of the linear axes are eliminated.A trial-cut experiment is performed to verify the correctness and the effectiveness of the proposed algorithm.展开更多
The automatic cutting of intersecting pipes is a challenging task in manufacturing.For improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a bra...The automatic cutting of intersecting pipes is a challenging task in manufacturing.For improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single Y-groove.Firstly,it summarizes the intersection forms and introduces a dual-pipe intersection model.Based on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is defined.Secondly,a novel mathematical model for plasma radius and taper compensation is established.Then,the compensation model and groove model are integrated by establishing movable frames.Thirdly,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is proposed.Through the established models and moving frames,the planned path description of cutting robot is provided in this novel scheme.The accuracy of the proposed method is verified by simulations and robotic cutting experiments.展开更多
文摘Cutter radius compensation （CRC） is a very important function of numerical control（NC） system. We refer to a large number of NC information and sum up the CRC function. We illustrate how to realize rough machining ＆ finish machining by the same program, machining matching surface by the same program, simplify pro- gramming methods, realize direct programming by parts contour, remove machining allowance by the increase of CRC value, control the parts size precision by adjusting the CRC value, state the essence of the CRC, and elucidate the physical meaning of the CRC value.
基金supported by the National Basic Research Program of China under Grant No.2011CB302400the National Key Technology Research and Development Program of China under Grant No.2012BAF13B08
文摘When the five-axis CNC system executes the 3D cutter radius compensation function,the angle between two adjacent radius compensation vectors might become very large and the linear axes would move too fast if the tool orientation vector is close to the surface normal.The reason that results in this phenomenon is analyzed based on building the transmission relationship between the cutter contact point and the cutter location point.By taking the square-end tool as an example,an optimization algorithm to control the undesired movements is advanced.For the singular area where sudden change exists,the number of interpolation cycles is determined by the cutter feedrate,the limit speeds of machine axes and the maximum allowable angle between radius compensation vectors of adjacent NC blocks.The radius compensation vector of each interpolation cycle is obtained by a kind of vector rotation method.By maintaining the perpendicularity between the radius compensation vector and the tool orientation vector,the rapid movements of the linear axes are eliminated.A trial-cut experiment is performed to verify the correctness and the effectiveness of the proposed algorithm.
基金the National Natural Science Foundation of China(Grant No.62103234)the Shandong Provincial Natural Science Foundation(Grant Nos.ZR2021QF027,ZR2022QF031).
文摘The automatic cutting of intersecting pipes is a challenging task in manufacturing.For improved automation and accuracy,this paper proposes a model-driven path planning approach for the robotic plasma cutting of a branch pipe with a single Y-groove.Firstly,it summarizes the intersection forms and introduces a dual-pipe intersection model.Based on this model,the moving three-plane structure(a description unit of the geometric characteristics of the intersecting curve)is constructed,and a geometric model of the branch pipe with a single Y-groove is defined.Secondly,a novel mathematical model for plasma radius and taper compensation is established.Then,the compensation model and groove model are integrated by establishing movable frames.Thirdly,to prevent collisions between the plasma torch and workpiece,the torch height is planned and a branch pipe-rotating scheme is proposed.Through the established models and moving frames,the planned path description of cutting robot is provided in this novel scheme.The accuracy of the proposed method is verified by simulations and robotic cutting experiments.
