@ARTICLE{Kumar_Virendra_Motion_2021, author={Kumar, Virendra and Sen, Soumen and Roy, Shibendu Shekhar}, volume={vol. 68}, number={No 4}, journal={Archive of Mechanical Engineering}, pages={415-434}, howpublished={online}, year={2021}, publisher={Polish Academy of Sciences, Committee on Machine Building}, abstract={The article describes motion planning of an underwater redundant manipulator with revolute joints moving in a plane under gravity and in the presence of obstacles. The proposed motion planning algorithm is based on minimization of the total energy in overcoming the hydrodynamic as well as dynamic forces acting on the manipulator while moving underwater and at the same time, avoiding both singularities and obstacle. The obstacle is considered as a point object. A recursive Lagrangian dynamics algorithm is formulated for the planar geometry to evaluate joint torques during the motion of serial link redundant manipulator fully submerged underwater. In turn the energy consumed in following a task trajectory is computed. The presence of redundancy in joint space of the manipulator facilitates selecting the optimal sequence of configurations as well as the required joint motion rates with minimum energy consumed among all possible configurations and rates. The effectiveness of the proposed motion planning algorithm is shown by applying it on a 3 degrees-of-freedom planar redundant manipulator fully submerged underwater and avoiding a point obstacle. The results establish that energy spent against overcoming loading resulted from hydrodynamic interactions majorly decides the optimal trajectory to follow in accomplishing an underwater task.}, type={Article}, title={Motion planning of planar and redundant underwater serial link manipulator based on minimization of energy consumption}, URL={http://journals.pan.pl/Content/121185/PDF-MASTER/AME_2021_139312.pdf}, doi={10.24425/ame.2021.139312}, keywords={underwater manipulator, drag, added inertia, motion planning, recursive Lagrangian formulation, redundant manipulator, obstacle avoidance, singularity avoidance}, }