Simulation and Experimental Research on Electrical Control Anti-backlash Based on a Novel Type of Variable Tooth Thickness Involute Gear Pair

Guangjian Wang,Xin Tian,Dongdong Zhu,Shuaidong Zou,Yujiang Jiang

doi:10.5545/sv-jme.2021.7452

Abstract

This paper presents an electrical backlash control method based on a novel variable tooth thickness involute gear pair (VTTIGP) through acceleration judgment. First, the principle, characteristics and theoretical tooth surface equation of the novel type of variable tooth thickness involute gear (VTTIG) are proposed. Compared with the traditional variable tooth thickness gear (VTTG), each transverse of the novel type of VTTIG has the same tooth root circle and the addendum circle. Therefore, there will be no interference caused by the excessive axial relative movement distance between the gear pairs when eliminating the backlash. The theoretical calculation equation of no-load transmission error (TE) and time-varying backlash for a dual-eccentric novel type of VTTIGP are deduced. Second, using the theoretical backlash equation and the eccentricities and the initial phases obtained through the experimental TE curve obtained with angular displacement sensors and the developed TE equation, the continuous backlash curve of the gear pair is obtained. Based on the RecurDyn software and its Colink control module, the co-simulation model of the novel type of VTTIGP and its backlash control system is used to explore the electrical backlash control method through acceleration judgment in the case of time-varying backlash. Finally, using angular displacement sensors and linear actuators, the experimental study on the anti-backlash control with different reversed positions under different input speeds is carried out, demonstrating that this novel electrical anti-backlash control method is effective.

Highlights

Gear transmission is widely used in precision servo transmission systems, such as robots, machine tools and tracking and positioning systems, which require fast responses, high positioning accuracy, and good stability [1] and [2]
The formula of the non-load TE and time-varying backlash based on the eccentricity error model of the novel type of VTTIG is derived
The simulation and experiment further verify the effectiveness of the electrical anti-backlash control method based on acceleration judgment

Summary

Introduction

Gear transmission is widely used in precision servo transmission systems, such as robots, machine tools and tracking and positioning systems, which require fast responses, high positioning accuracy, and good stability [1] and [2]. Gears will cause errors in the process of machining and assembly, and these errors often affect the backlash of the gear transmission process [1] and [3]. Gear backlash is a nonlinear factor affecting gear performance [4]. The non-linearity of the gear tooth backlash will directly affect the stability, accuracy, and sensitivity of the servo control, resulting in delay and discontinuity of the output motion response [5] to [8]. Adjusting and controlling the gear backlash is of great significance to improve the accuracy of the transmission system. It is necessary to adopt special anti-backlash mechanisms and technical measures to eliminate backlash when the machining and assembly accuracy reaches a certain level [9] and [10]. The commonly used anti-backlash methods include adjustable centre distance, springloaded gears, fixed split gears, and adjustable tooth thickness gear [10] and [11]

Objectives

Methods

Results