Abstract:
A task-oriented design strategy is presented in this paper for service manipulators. The tasks are normally defined in the form
of working locations where the end-effector can work while avoiding the obstacles. To acquire feasible solutions in cluttered
environments, the robotic parameters (D-H parameters) are allowed to take unconventional values. This enhances the solution
space and it is observed that, by inducing this flexibility, the required number of degrees of freedom for fulfilling a given task can be
reduced. A bilevel optimization problem is formulated with the outer layer utilizing the binary search method for minimizing the
number of degrees of freedom. To enlarge the applicability domain of the proposed strategy, the upper limit of the number of joints
is kept more than six. These allowable redundant joints would help in providing solution for intricate workcells. For each iteration
of the upper level, a constrained nonlinear problem is solved for dimensional synthesis of the manipulator. The methodology is
demonstrated through a case study of a realistic environment of a cluttered server room. A 7-link service arm, synthesized using
the proposed method, is able to fulfill two different tasks effectively.
