Trajectory Planning of a 6D Robot based on Meta Heuristic Algorithms Kritsada Wichapong, Nantiwat Pholdee, Sujin Bureerat and Thana Radpukdee MATEC Web Conf., 220 (2018) 06004 Published online: 29 October 2018 DOI: 10.1051/matecconf/201822006004