Method for synchronized multi-axis motion control of flexible electronic gearbox

A method for synchronized multi-axis motion control of a flexible electronic gearbox, wherein the method for synchronized multi-axis motion control is suitable for a CNC gear bobbing machine;

• the gear hobbing machine comprises an A axis, a B axis, a C axis, an X axis, a Y axis and a Z axis, the A axis serves as a reference for adjusting a hob installation angle, the B axis serves as a reference for hob rotation, the C axis serves as a reference for workpiece rotation, the X axis serves as a reference for hob radial feeding, the Y axis serves as a reference for hob tangential feeding, the Z axis serves as a reference for hob axial feeding, wherein the B axis, the X axis, the Y axis and the Z axis are main motion axes;
• a servo motor of each main motion axis is detected by a grating encoder and detection results are then input into a microprocessor as reference data, detections results of the B axis, Y axis and Z axis (excluding the X axis) obtained after a functional module of the flexible electronic gearbox performs calculation and transformation according to a mathematical model of a gear bobbing machining technology serve as working data of the C axis, a motion law specified by an electronic gearbox module is realized by using a control theory algorithm to realize gear bobbing machining;
• the flexible electronic gearbox realizes control functions based on an ARM-DSP-FPGA based hardware platform, wherein
• according to a machining principle of the CNC gear hobbing machine, a functional relation between a geometric error of a gear and a tracking error of each motion axis of the machine tool is constructed;
• the tracking errors comprise:
• a B axis tracking error Eb (a hob rotation axis tracking error Eb), a C axis tracking error Ec (a workpiece rotation axis tracking error Ec), a Z axis tracking error Ez (a hob axial feed axis tracking error Ez), a Y axis tracking error Ey (a hob tangential feed axis tracking error Ey), an X axis tracking error Ex (a hob radial feed axis tracking error Ex) and a hob installation angle error Ea;
• a machining error mathematical model of tooth profile deviation Fα, tooth pitch deviation FP and spiral deviation Fβ is established by tracking errors of each motion axis, and the geometric error of the gear is evaluated by using numerical results of the machining error mathematical model;
• through each motion axis error of each position control time point, machining error values of this time point, namely the value of the tooth profile deviation Fα, the value of the tooth pitch deviation FP and the value of the spiral deviation Fβ, are calculated;
• based on a principle of cross-coupling control, a decoupling compensation model is established to calculate a compensation quantity ΔEc required for the C axis;
• the compensation quantity ΔEc is compensated to the C axis at the next position control time point, and the compensated machining error values, namely the compensated value of the tooth profile deviation Fα, the compensated value of the tooth pitch deviation FP and the compensated value of the spiral deviation Fβ, are calculated through tracking errors of each motion axis at the time point;
• meanwhile, the synchronized multi-axis motion control of the total position control time is completed by obtaining average absolute values of the machining errors and the total compensation quantity of the machining errors under the conditions of not adopting the synchronous control method and adopting the synchronous control method in the total position control time.