As the end-effector of robot, the induction hard- ening tool is required to keep its orientations perpendicular to the fillets or chamfers of the mould at a distance during its uniform motion along the hardening traje...As the end-effector of robot, the induction hard- ening tool is required to keep its orientations perpendicular to the fillets or chamfers of the mould at a distance during its uniform motion along the hardening trajectory. This trajectory consists of a group of central curves which are parametric curves on the corresponding chamfers or fillets and between two edges of every chamfer or fillet. The trajectory points and the surface normal vectors at these points are obtained by parametric equations of the fillets or chamfers. This study is conducted to join each central curve into the entire hardening trajectory, including handling on the irregular surfaces and unifying the directions of hardening tool motion. According to kinematics of robot, the trajectory points in modeling coordinate system are transferred into the poses of the induction hardening tool in user frame of robot. The kinematical interference of the induction hardening tool and robot joints is checked by Robognide sim- ulation tool. The validity of the robotic off-line programming （OLP） system was verified by experiments.展开更多
The span and length to diameter ratio of the large-scale crankshaft are big, and the structure and the distribution of crank pins are complex. Thus it is easier for crankshaft to generate biggish torsional deflection ...The span and length to diameter ratio of the large-scale crankshaft are big, and the structure and the distribution of crank pins are complex. Thus it is easier for crankshaft to generate biggish torsional deflection which finally influences the contour precision of the crank pin in tangential point tracing grinding. Based on the analyses of force and torsional deformation of the crankshaft under different crankshaft driving modes of the headstock and the tailstock, the relationship between torsional deformation and rotation angle error of the crankshaft in tangential point tracing grinding is discussed in this paper. According to crankshaft rotational motion and wheel frame coordinated motion in tangential point tracing grinding, contour error of the crank pin caused by torsional deflection is established under different crankshaft driving modes. The simulation results show that minimum contour error of the crank pin can be obtained when crankshaft is synchronously driven by both the headstock and the tailstock, and speed error does not exist in tangential point tracing grinding.展开更多
文摘As the end-effector of robot, the induction hard- ening tool is required to keep its orientations perpendicular to the fillets or chamfers of the mould at a distance during its uniform motion along the hardening trajectory. This trajectory consists of a group of central curves which are parametric curves on the corresponding chamfers or fillets and between two edges of every chamfer or fillet. The trajectory points and the surface normal vectors at these points are obtained by parametric equations of the fillets or chamfers. This study is conducted to join each central curve into the entire hardening trajectory, including handling on the irregular surfaces and unifying the directions of hardening tool motion. According to kinematics of robot, the trajectory points in modeling coordinate system are transferred into the poses of the induction hardening tool in user frame of robot. The kinematical interference of the induction hardening tool and robot joints is checked by Robognide sim- ulation tool. The validity of the robotic off-line programming （OLP） system was verified by experiments.
基金supported by Major National Science and Technology Projects(Grant No.2013ZX04002-031)
文摘The span and length to diameter ratio of the large-scale crankshaft are big, and the structure and the distribution of crank pins are complex. Thus it is easier for crankshaft to generate biggish torsional deflection which finally influences the contour precision of the crank pin in tangential point tracing grinding. Based on the analyses of force and torsional deformation of the crankshaft under different crankshaft driving modes of the headstock and the tailstock, the relationship between torsional deformation and rotation angle error of the crankshaft in tangential point tracing grinding is discussed in this paper. According to crankshaft rotational motion and wheel frame coordinated motion in tangential point tracing grinding, contour error of the crank pin caused by torsional deflection is established under different crankshaft driving modes. The simulation results show that minimum contour error of the crank pin can be obtained when crankshaft is synchronously driven by both the headstock and the tailstock, and speed error does not exist in tangential point tracing grinding.
