Collision avoidance analysis of human-robot physical interaction based on null-space impedance control of a dynamic...

Area of Science:

• Robotics
• Biomechanics
• Rehabilitation Engineering

Background:

• Rehabilitation robots assist upper limb motion.
• Redundant manipulators can collide with patients due to null-space self-motion.
• Ensuring safety during human-robot interaction is critical.

Purpose of the Study:

• To propose a null-space impedance control method for collision avoidance.
• To enhance safety and feasibility in robot-assisted rehabilitation.
• To manage null-space self-motion in redundant manipulators.

Main Methods:

• Developed a dynamic model and Cartesian impedance controller for the manipulator.
• Established a null-space impedance controller using a dynamic reference arm plane.
• Managed null-space self-motion to prevent link-human collisions.

Main Results:

• Experimental verification confirmed effective management of null-space self-motion.
• The proposed method successfully achieved collision avoidance during interaction.
• Demonstrated improved safety and feasibility for motion-assisted training.

Conclusions:

• The null-space impedance control method ensures safe human-robot interaction.
• This approach significantly enhances the safety of upper limb rehabilitation robots.
• The technique holds potential for broader applications in physical interaction robotics.