To overcome the disadvantages of conventional computed-torque control and fuzzy control, and to exploit their attractive features, this paper proposes two types of adaptive control scheme combining conventional computed-torque control and different fuzzy compensators for the robust tracking control of robotic manipulators with structured and unstructured uncertainties. Fuzzy compensators based on feed-forward and feed-back are developed to compensate these uncertain dynamics. On the basis of Lyapunov stability theory, a tracking error limit is derived for the closed-loop control system and the convergence and stability of the control schemes are proved. Comparisons of their performances with conventional computed-torque controllers under the condition of these uncertainties are carried out. The validity of the two types of adaptive control scheme is shown by numerical simulations of a three-link rotary robot manipulator.
A new type of space structure called the double inner and outer latticed shell string structure, which can reduce the space occupied by the roof and be laid easily using a rigid roofing material, is proposed. Numerical algorithm for shape determination of this new space structure is introduced and some suggestions for improvement are put forward. One example is investigated and the results confirm the validity of the above method. Finally, a model experiment based on a practical engineering application is introduced. Experimental results are compared with those of the finite element numerical analysis and results show that the theoretical value and the experimental value match well, which reveals that the model design, loading scheme and measuring plan meets experimental requirements. The internal forces and the structure deformation vary linearly for full span load cases, which reveals that the double inner and outer latticed shell string structure has an excellent load-carrying capacity and structural rigidity, and has broad application prospects.
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