Human–robot collision model with effective mass and manipulability for design of a spatial manipulator

Abstract

As the use of service robots becomes more popular, many solutions to ensure human safety during human-robot collision have been proposed. In this paper, we address one of the most fundamental solutions to design an inherently safe robot manipulator. A collision model is developed to evaluate the collision safety of any spatial manipulator. Most collision studies have focused on collision analysis and safety evaluation, but not on the use of evaluation results to design a safer robot arm. Therefore, we propose a collision model that relates design parameters to collision safety by adopting effective mass and manipulability. The model was then simplified with several assumptions. Furthermore, experimental results from biomechanical literature were employed to describe a human-robot collision. The major advantage of this collision model is that it can be used to systemically determine the design parameters of a robot arm.

Sensorless collision detection for safe human-robot collaboration

“…Therefore, we adopted the JTS-based external torque observer used to detect collisions in previous studies [4,10], and this observer can be designed without considerations of modeling friction torques as follows:…”

“…In case of malfunctions or misuses of the robot, the importance of human-robot collision safety has been receiving much attention from workers and researchers. There have been several suggestions regarding this matter, such as installing a passive mechanism for absorption of damage [1,2], avoiding the collision in the first place by using a vision sensor [3], and the design and control scheme of manipulators based on collision analysis and safety evaluations [4,5]. These methods have shown their effectiveness but a single method is not the best way to solve the problem as they all show a number of weaknesses.…”

Disturbance Recognition and Collision Detection of Manipulator Based on Momentum Observer

“…Optimizing human-robot collision detection in unpredictable environments is the most critical and urgent issue facing collaborative robots. At present, some scholars have made efforts in this area and achieved certain achievements [ 6 , 7 , 8 ].…”

Toward Tradeoff Between Impact Force Reduction and Maximum Safe Speed: Dynamic Parameter Optimization of Variable Stiffness Robots

“…However, these requirements sacrifice robot speed and efficiency. To have a better tradeoff between the safety and speed, there have been several interesting concepts toward these two goals, ranging from mechanical designs [2][3][4], controls [5][6][7][8][9], to motion planning [10][11][12]. Among those approaches, the variable stiffness (VS) concept is promising because it may address both safety and efficiency simultaneously.…”

“…[21] to describe how mass/inertial properties, kinematic configurations, and impact direction affect the impact. The concept of impact ellipsoid and its variants have been used in design optimization [3] and planning [22] for traditional CS robots. For VS robots, flexibility plays an important role in the impact ellipsoid.…”