对于基于FS⁃SEA（力源串联弹性驱动器）的柔性关节机械臂，当其动力学模型已知时，反馈计算力矩法是一种非常直观的控制方法。但是对于一个动力学参数难以精确确定，并且可能受到冲击扰动的系统来说，传统的反馈计算力矩法难以进行稳定地控制。在传统的反馈计算力矩法基础上，提出了一种改进的控制方法。通过在控制律中引入自适应补偿项，保证了控制系统在机械臂动力学参数或所受外力无法精确估计情况下的渐近稳定性；通过在系统的加速度指令之后引入低通滤波环节，大幅度增强了控制系统抵抗外部冲击的能力。仿真实验证明，利用改进的反馈计算力矩法对FS⁃SEA柔性机械臂进行控制，不仅能够保证系统稳定性，实现高精度轨迹跟踪，而且使控制系统具有很强的抗冲击能力。%For flexible⁃joint manipulators based on FS⁃SEA ( force sourced series elastic actuator) , when their dynamic models are known, the feedback computed torque method is a very intuitional control method. However, for a system whose dynamic parameters are difficult to be determined ac⁃curately, which probably suffers an external impact as well, the traditional feedback computed torque method can hardly make a stable control. This paper proposed an improved control method based on the traditional feedback computed torque method. Through introducing an adaptive com⁃pensation term into the control law, the asymptotic stability of the control system was guaranteed in the case of inaccurate estimation of the manipulator’ s dynamic parameters or external force;through introducing a low⁃pass filter after the system’ s acceleration command, the control system’ s ability of resisting external impacts was enhanced significantly. The simulations demonstrated that controlling FS⁃SEA flexible manipulators with the improved feedback computed torque method could not only ensure system stability and tracking accuracy, but also offer the control system very strong impact re⁃sisting capability.
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