The invention relates to a mechanical arm trajectory tracking method based on improved integral
terminal sliding mode control, and belongs to the technical field of
robot control. According to the method, an
integral sliding mode surface and a fast
terminal sliding mode surface are combined to create a non-singular fast integral
terminal sliding mode surface; an improved index reaching law is designed, and the buffeting problem existing in
sliding mode control is weakened. The method comprises the following steps: S1, based on physical parameters of the mechanical arm, establishing a mechanical arm dynamic model by adopting a DH parameter method and a Lagrange dynamics principle; s2, constructing a non-singular fast integral terminal sliding mode surface for the dynamic
system; s3, designing an improved reaching law fused with a
hyperbolic tangent function; s4, performing
trajectory planning by using a Cartesian space interpolation
algorithm; s5, integrating the sliding mode surface, the improved reaching law and the dynamical model to derive a trajectory tracking control law; s6, constructing a closed-
loop control model of the improved integral terminal sliding mode controller and the mechanical arm
system; and S7, the
control parameters are adjusted, and mechanical arm trajectory tracking is conducted. The control method serves as a controller to conduct trajectory tracking application on the six-degree-of-freedom mechanical arm. The result shows that on the premise of ensuring
finite time convergence, the control method effectively eliminates the buffeting phenomenon of traditional
sliding mode control, improves the trajectory tracking precision, has high robustness to external disturbance, and can realize high-precision tracking control of a mechanical arm end
effector on a complex trajectory.