Effect of presenting robot hand stiffness to human arm on human-robot collaborative assembly tasks

Area of Science:

• Robotics
• Human-Robot Interaction
• Collaborative Assembly

Background:

• Human-robot collaboration (HRC) is crucial for complex tasks, with adaptive responses and motion cues enhancing collaboration.
• Existing HRC methods struggle with precise tasks like collaborative assembly, where shared object interactions compromise accuracy and smoothness.

Purpose of the Study:

• To propose and evaluate a novel method for conveying robot stiffness to a human arm during collaborative assembly.
• To enhance task efficiency and reduce human workload without compromising the shared object or task.

Main Methods:

• A within-subjects experiment with 16 participants performing a collaborative assembly task involving part manipulation by a robot.
• The robot's stiffness was communicated to the participant's forearm using real-time and predictive presentation methods, compared to a no-presentation control.

Main Results:

• The proposed stiffness communication method significantly enhanced task efficiency by reducing task completion time.
• Participants reported lower subjective workload scores when using the stiffness communication method.

Conclusions:

• Communicating robot stiffness directly to the human arm is an effective strategy for improving HRC in precise assembly tasks.
• This method offers a promising approach to increase efficiency and decrease physical and cognitive load in human-robot teams.