Researchers at the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) have successfully utilized robotic assistance in the production of wind turbine blades, leading to improved working conditions and potential product consistency.
While robots have been employed in the wind energy industry for tasks like painting and polishing blades, automation has not been widely adopted. Research at NREL has shown that a robot can effectively trim, grind, and sand blades, tasks that occur after the two sides of the blade are created using a mold and then bonded together.
“I would consider it a success,” said Hunter Huth, a robotics engineer at NREL and the lead author of a newly published paper detailing the work. “Not everything went as smoothly as we hoped, but we have learned valuable lessons that we believe will help us meet or exceed our expectations.”
The paper, titled “Toolpath Generation for Automated Wind Turbine Blade Finishing Operations,” is published in the journal Wind Energy. The coauthors, all from NREL, include Casey Nichols, Scott Lambert, Petr Sindler, Derek Berry, David Barnes, Ryan Beach, and David Snowberg.
Post-molding operations in wind turbine blade manufacturing require workers to work on scaffolding and wear protective gear, including respiratory equipment. Automation, the researchers noted, will enhance employee safety and well-being and assist manufacturers in retaining skilled labor.
“This work is crucial for enabling significant U.S.-based blade manufacturing for the domestic wind turbine market,” said Daniel Laird, director of the National Wind Technology Center at NREL. “By automating some of the labor in blade production, it can lead to more jobs in the U.S. as it improves the economics of domestic blades compared to imported ones.”
“The goal of this research was to develop automation techniques that could make domestically manufactured blades globally competitive in terms of cost,” Huth explained. “Currently, offshore blades are not produced in the U.S. due to high labor costs. The finishing process is labor-intensive and has a high turnover rate due to the harsh working conditions. By automating the finishing process, domestic offshore blade manufacturing can become more economically feasible.”
The research took place at the Composites Manufacturing Education and Technology (CoMET) facility at NREL’s Flatirons Campus, where the robot worked on a 5-meter-long blade segment. Wind turbine blades are longer, but due to their bending nature, a robot would need to work on larger blades section by section.
The researchers used scans to create a 3D representation of the blade’s position and identify the front and rear sections of the airfoil. They then programmed the robot to perform tasks, evaluating its accuracy and speed. Areas for improvement were identified, particularly in grinding, where the robot was inconsistent in removing material.
“Through this research, we have continually raised the bar for what this system needs to achieve to be effective,” Huth said.
The robot’s performance was not compared to that of a human performing the same tasks.
Huth stated that an automated system would provide consistency in blade manufacturing that is unattainable when relying solely on human labor. Additionally, a robot could utilize more aggressive abrasives that a human operator could not tolerate.
