Behavioural Study of the Force Control Loop Used in a Collaborative Robot for Sanding Materials

Area of Science:

• Robotics
• Manufacturing Engineering
• Materials Science

Background:

• Collaborative robots (cobots) are increasingly adopted for industrial tasks.
• Orbital sanding is a common industrial finishing process.
• Evaluating cobot feasibility for sanding is crucial for automation.

Purpose of the Study:

• To demonstrate the feasibility of using collaborative robots for orbital sanding.
• To assess cobot performance across diverse materials (aluminum, steel, brass, wood, plastic).
• To investigate the impact of control strategies and operational parameters on sanding quality.

Main Methods:

• Utilized a collaborative robot with adjusted tools and working conditions.
• Implemented an inner/outer control loop strategy combining motion and force control.
• Conducted experiments on various materials to evaluate performance and control stability.
• Analyzed the relationship between applied force, feed rate, and surface finish.

Main Results:

• Orbital sanding was successfully performed on all tested materials with a mean force error of 0.32%.
• Cobots achieved comparable results to industrial robots for sanding tasks.
• Increased applied force did not correlate with improved surface finish.
• Feed rate variations showed minimal impact on finish quality, indicating a saturation state.

Conclusions:

• Collaborative robots are viable for orbital sanding operations across multiple materials.
• Cobot sanding performance is comparable to traditional industrial robots.
• Optimizing feed rate, rather than increasing force, can enhance productivity without compromising finish quality.