机器人关节裂纹传动系统机电耦合动态特性研究

服务机器人关节采用驱控一体化集成设计，并且传动系统采用小模数变位齿轮。关节频繁运动容易导致齿轮传动系统产生裂纹，裂纹引起刚度变化从而影响整个系统的动态特性。根据变位齿廓建立变位齿轮裂纹刚度计算模型，分别研究变位系数、多种裂纹形式对时变啮合刚度的影响；其次利用集中参数法构建了机器人关节机电耦合平移—扭转动力学模型，并将驱动电机的电磁特性、齿侧间隙等因素考虑入方程中；最后通过统计学分析裂纹对传动系统的影响。研究结果表明：正变位使刚度增大，负变位反之；双侧裂纹对刚度的影响明显大于单侧；随着裂纹加深，时变啮合刚度加速降低；随着传动系统级数的增加，裂纹对传动系统的影响逐渐减弱。研究结果为变位齿轮传动系统裂纹故障诊断提供理论基础。

Research on Dynamic Characteristics of Electromechanical Coupling of Robot Joint Crack Transmission System

The joint of the service robot adopts the integrated design of drive and control, and the transmission system adopts the small-modulus modified gear. The frequent movement of joints can easily lead to cracks in the gear transmission system, and the cracks cause stiffness changes that affect the dynamic characteristics of the entire system. According to the modified tooth profile, a calculation model of the crack stiffness is established. Study on the influence of modified coefficient and various crack forms on time-varying mesh stiffness. Secondly, the electromechanical coupling translation-torsion dynamic model of the robot joint is constructed by the lumped parameter method, and the electromagnetic characteristics of the drive motor and the backlash and other factors are taken into account into the equation. Finally, the influence of the crack on the transmission system is analyzed by statistics. The research results show that positive modified increases the stiffness, while negative modified is the opposite; the effect of double-sided cracks on stiffness is significantly greater than that of single-sided cracks; as the crack deepens, the stiffness decreases rapidly. The effect of cracks on the transmission system is gradually weakened with the increase of the transmission system grade. The research results provide a theoretical basis for the crack fault diagnosis of the modified gear transmission system.