With a linear PID controller used in contact period, a sliding control with PTO surface is switched into when system enters the backlash.

• 以具有代表性的双电机驱动齿隙非线性系统为对象,研究了冗余驱动系统(齿隙非线性传动系统由施加偏置力矩的两组驱动子系统和一组从动子系统组成)的基于Backstepping方法的齿隙非线性控制问题。