# Integrated Motion Planning for Assembly Task with Part Manipulation Using Re-Grasping
## 3 Feasible Grasp, Part Manipulation, and Integrated Planning Algorithm
### Integrated Part Manipulation and Robot Motion Planner
## 5 Conclusions and Future Work

This paper proposed an integrated planning algorithm to perform an assembly task using robotic manipulator. The algorithm takes into account the geometry of parts and their initial, and final poses to choose feasible grasps. Afterwards, it chooses a feasible grasp while planning motion of manipulator to perform assembly task. For this, each node in the tree is associated with one of the feasible grasp for each parts yet to be assembled. If the part manipulation is necessary to do an assembly operation, a re-grasping approach is proposed using orientation graph search (for each part). The algorithm finds the sequences of poses of a part between its initial and final poses so that the part can be assembled without interfering the obstacles in the environment. While assembly multiple parts, the task space undergoes changes at every step of assembly, making some previously collision-free nodes be in collision. To handle this and to be able to use the disconnected parts of the tree, a two-stage-extend-RRT method is proposed in which while growing a tree, attempts are made to reconnect the disconnected parts to the main tree. The motion planning to perform an assembly operation is inherently a multi-query problem. While planning feasible configuration space paths for grasping a part and assembling it, often they are connected through the root node of the tree, resulting in an inefficient path. One can optimize the solution after finding the collision free paths of the assembly operation or reconnect the disconnect trees so that the path between the start and the target poses are in general shorter. In addition, the proposed planner considers a pre-computed set of grasps are given at the beginning. Later on, it chooses feasible grasp during the motion planning phase. In future work, the authors are intended to integrate the grasp planning in the algorithm. In future, the authors are intended to incorporate the safety issue while planning and executing the algorithm using proximity sensor such as [10; 29]. The following are available online at [[http://www.mdpi.com/2076-3417/10/3/749/s1](http://www.mdpi.com/2076-3417/10/3/749/s1)]([http://www.mdpi.com/2076-3417/10/3/749/s1](http://www.mdpi.com/2076-3417/10/3/749/s1)). This research work was conducted jointly by A.A. and J.Y.L. This research idea was proposed and supervised by [PERSON]. The I implementation and experiments were conducted by [PERSON] All authors have read and agreed to the published version of the manuscript. This work was supported by the Technology Innovation Program (or Industrial Strategic Technology Development Program) (20001856, Development of robotic work control technology capable of grasping and manipulating various objects in everyday life environment based on multimodal recognition and using tools) funded By the Ministry of Trade, Industry & Energy (MOTIE, Korea). The authors declare no conflict of interest. ## References

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