Parametric Trajectory Optimisation for Increased Payload

Abstract

The load-carrying capacity of manipulators is often considered to be the same throughout their workspace. However, the actual capacity of manipulators largely depends on their posture, their velocity, their acceleration and the limits of their actuators. In this paper, a method is proposed to increase the payload capacity of manipulators through trajectory optimisation. This optimisation is performed on a task basis and therefore, the load-carrying capacity varies from task to task. An extensive analysis of the method is conducted based on its application on a planar RR serial two degree-of-freedom manipulator. This analysis evaluates the ability of the method to find feasible trajectories and compares the results with those obtained using Bang-bang type methods. It is shown that, although the trajectories produced by the proposed method are not time optimal, the method is much more versatile and much simpler to implement than its Bang-bang counterparts.

Solving nonlinear optimal path tracking problem using a new closed loop direct–indirect optimization method: application on mechanical manipulators

“…By definition of an additional state variable x n+1 and differential Eq. 13, the performance index can be defined as the standard Mayer form (14).…”

“…Using Eqs. (13) and (14), the optimization problem defined by Algorithm 1 is converted to the following Mayer form optimization. Algorithm 2.…”

“…In ref. [14], a method is proposed to increase the DLCC of the manipulator through trajectory optimization. In ref.…”