The guiding device in the mechatronic system is generally a guide rail, which consists of a moving part and a supporting part. When various machines are running, the guide rail pair ensures the correct motion trajectory of the actuator. The guide rail pair also affects the motion characteristics of the actuator.
As a guiding device, the guide rail should have the following performance:
(1) Guiding accuracy: This mainly refers to the accuracy of the guide rail's motion trajectory. The main factors affecting the guiding accuracy are: the geometric accuracy and contact accuracy of the guide rail, the structural form of the guide rail, the stiffness and thermal deformation of the guide rail and its supporting parts, the oil film thickness and stiffness between the static (dynamic) pressure guide rail pair, etc.
(2) Accuracy retention: This is mainly determined by the wear resistance of the guide rail. Wear resistance is related to factors such as the material of the guide rail, the friction properties of the guide rail pair, the pressure on the guide rail and its distribution law.
(3) Stiffness: This includes the guide rail's own stiffness and contact stiffness. It mainly depends on factors such as the shape and size of the guide rail and the connection method and stress conditions of the supporting parts.
(4) Smoothness of low-speed motion When the moving guide rail moves at low speed or with a small displacement, it is easy to generate friction self-excited vibration, that is, creeping. Creeping will reduce positioning accuracy or increase the roughness of the workpiece surface.