Force Balancing of Robotic Mechanisms Based on Adjustment of Kinematic Parameters

Abstract

Force balancing is a very important issue in mechanism design and has only recently been introduced to the design of robotic mechanisms. In this paper, a force balancing method called adjusting kinematic parameters (AKP) for robotic mechanisms or real-time controllable (RTC) mechanisms is proposed, as opposed to force balancing methods, e.g., the counterweights (CW) method. Both the working principle of the AKP method and the design equation with which to construct a force balanced mechanism are described in detail. A particular implementation of the AKP method for the RTC mechanisms where two pivots on a link are adjustable is presented. A comparison of the two methods, namely the AKP method and the CW method, is made for two RTC mechanisms with different mass distribution. The joint forces and torques are calculated for the trajectory tracking of the RTC mechanisms. The result shows that the AKP method is consistently better than the CW method in terms of the reduction of the joint forces and the torques in the servomotors, and the smoothing of the fluctuation of the joint force.

An adaptive switching learning control method for trajectory tracking of robot manipulators

“…The time duration between two nearby points was 0.25 s. The control was carried out at the joint level where the inverse kinematics was used to calculate the joint position and velocity associated with the specific path of the end-effector. The path was designed to pass through these three points with the objective of meeting the positions, velocities, and accelerations at these three points using the motion planning method [24].…”

A Review of Dynamic Balancing for Robotic Mechanisms

“…As one can imagine, the major disadvantage of the above approach is that it limits the end-effector trajectory. Another study 76 which is worth mentioning is that through adjusting kinematic parameters and therefore the end-effector trajectories, the force balancing condition is achieved, but it does not apply to the dynamic balancing.…”

Design of Reactionless Linkages and Robots Equipped with Balancing Assur Groups

“…For robots, shaking force balancing is mostly obtained via an optimal redistribution of movable masses [7][8][9][54][55][56][57][58][59][60] or adjustment of kinematic parameters [61]. The cancellation of the shaking moment is a more complicated task and can be obtained using three main different methods: Previous works have been devoted to the study of parallel manipulators with revolute joints and few studies has been carried out on complete shaking force and shaking moment balancing of parallel manipulators with prismatic pairs.…”