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In this study, the researchers try to examine nonlinear dynamic analysis and determine Dynamic load carrying capacity (DLCC) in flexible manipulators. Manipulator modeling is based on Timoshenko beam theory (TBT) considering the effects of shear and rotational inertia. To get rid of the risk of shear locking, a new procedure is presented based on mixed finite element formulation. In the method proposed, shear deformation is free from the risk of shear locking and independent of the number of integration points along the element axis. Dynamic modeling of manipulators will be done by taking into account small and large deformation models and using extended Hamilton method. System motion equations are obtained by using nonlinear relationship between displacements-strain and 2nd PiolaKirchoff stress tensor. In addition, a comprehensive formulation will be developed to calculate DLCC of the flexible manipulators during the path determined considering the constraints end effector accuracy, maximum torque in motors and maximum stress in manipulators. Simulation studies are conducted to evaluate the efficiency of the method proposed taking two-link flexible and fixed base manipulators for linear and circular paths into consideration. Experimental results are also provided to validate the theoretical model. The findings represent the efficiency and appropriate performance of the method proposed.

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This paper aims at planning an optimal point to point path for a flexible manipulator under large deformation. For this purpose, the researchers use a direct method and meta-heuristic optimization process. In this paper, the maximum load carried by the manipulator and the minimum transmission time are taken as objective functions of the optimization process to get optimal path profiles. Kinematic constraints, the maximum velocity and acceleration, the dynamic constraint of the maximum torque applied to the arms and also the constraint of final point accuracy are discussed. For the optimization process, the Harmony Search (HS) method is used. To evaluate the effectiveness of the approach proposed, simulation studies are reviewed by considering a two-link flexible manipulator with the fixed base. The findings indicate that the proposed method is in power of dealing with nonlinear dynamics of the system. Furthermore, the results obtained by rigid, small and large deformation models are compared with each other.