Development of an Improved Stiffness Ellipsoid Method for Precise Robot-Positioner Collaborative Control in Friction...

Area of Science:

• Robotics
• Manufacturing Engineering
• Materials Science

Background:

• Robotic arms are crucial for automated manufacturing processes like friction stir welding (FSW).
• Ensuring high stiffness and precision in robotic arms is vital for weld quality and consistency.
• Existing methods for evaluating robotic arm performance may not adequately address variable loads in FSW.

Purpose of the Study:

• To propose an improved stiffness ellipsoid method for robotic arms used in FSW.
• To enhance the stiffness and precision of robotic arms during FSW operations.
• To develop a novel stiffness index for evaluating robot performance under dynamic FSW conditions.

Main Methods:

• Establishing a joint stiffness model using static identification experiments.
• Developing a novel stiffness index based on the improved stiffness ellipsoid method.
• Conducting simulation experiments to validate the proposed method.

Main Results:

• Significant improvements in welding trajectory precision were observed.
• Enhanced computational efficiency was achieved through the new method.
• The novel stiffness index effectively evaluates robot performance under variable FSW loads.

Conclusions:

• The improved stiffness ellipsoid method enhances robotic arm stiffness and precision for FSW.
• The developed stiffness index offers a refined metric for robot performance evaluation in FSW.
• This approach has the potential to significantly elevate FSW quality and consistency.