Singular Configuration Analysis and Singularity Avoidance with Application in an Intelligent Robotic Manipulator

Abstract

Recently, robotic sensor systems have gained more attention annually in complex system sense strategies. The robotic sensors sense the information from itself and the environment, and fuse information for the use of perception, decision, planning, and control. As an important supplement to traditional industrial robots, co-bots (short for co-working robots) play an increasingly vital role in helping small and medium-sized enterprises realize intelligent manufacturing. They have high flexibility and safety so that they can assist humans to complete highly repetitive and high-precision work. In order to maintain robot safe operation in the increasing complex working environment and human–computer intelligent interactive control, this paper is concerned with the problem of applicant accuracy analysis and singularity avoidance for co-bots. Based on the dynamic model with load and torque sensors, which is used to detect the external force at the end of the robot, this paper systematically analyzes the causes of singularity phenomenon in the robot motion control. The inverse solution is obtained by analytical method and numerical method, respectively. In order to ensure the smooth and safe operation in the whole workspace, it is necessary for a robot to avoid singularity. Singularity avoidance schemes are utilized for different control tasks, including point-to-point control and continuous path control. Corresponding simulation experiments are designed to verify the effectiveness of different evasion schemes, in which the advantages and disadvantages are compared and analyzed.

Exoskeleton Design Using Kinematics Analysis for Upper Limb Rehabilitation in Post-Stroke Patients

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Singularity Avoidance for Cart-Mounted Hand-Guided Collaborative Robots: A Variational Approach

“…As is well known, singularity is an essential problem related to the kinematics of robotic arms [26][27][28][29][30][31]. Using q and p to denote the joints, and the end-effector pose variables, respectively, the differential kinematics are described by…”

A computationally effective singularity avoidance method for redundant manipulators with non-spherical wrists

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