This paper presents a control method for the problem of trajectory jitter and poor tracking performance of the end of a three-joint rigid manipulator. The control is based on a high-order particle swarm optimization algorithm with an improved sliding mode control neural network. Although the sliding mode variable structure control has a certain degree of robustness, because of its own switching characteristics, chattering can occur in the later stage of the trajectory tracking of the manipulator end. Hence, on the basis of the high-order sliding mode control, the homogeneous continuous control law and super-twisting adaptive algorithm were added to further improve the robustness of the system. The radial basis function neural network was used to compensate the errors in the modeling process, and an adaptive law was designed to update the weights of the middle layer of the neural network. Furthermore, an improved particle swarm optimization algorithm was established and applied to optimize the parameters of the neural network, which improved the trajectory tracking of the manipulator end. Finally, MATLAB simulation results indicated the validity and superiority of the proposed control method compared with other sliding mode control algorithms.

In order to further improve the operating efficiency of wind turbines and explore the aerodynamic performance of the complex motion of wind turbine blades under yaw loads. In this study, the change in the angle of attack of the blade section airfoil under yaw load can be modeled as an oscillating airfoil and combined with the blade's flapwise motion. The NREL S809 airfoil are chosen for the research, based on the SST k-ω turbulence model with transition correction, under the condition of Reynolds number of 10 6 . The effect of phase difference on its aerodynamic performance under combined flapwise and pitching motion in various flapwise amplitudes and working conditions were analyzed. For the combined oscillations, the effects of the flapwise amplitude ( h ) in the range of 0.2≤ h ≤0.5 are investigated with the phase differences of Φ=±3π/4, ±π/2, ±π/4, 0. The results show that the phase difference between the pitching motion and the flapping motion and the different flapping amplitudes can have a large impact on the aerodynamic performance of the airfoil during dynamic stall, but the degree of influence is greatly different in different situations.