Industrial robots have been used in many different applications either on a small or medium-scale. However, using this technology on large-scale applications such as aerospace manufacturing, ship building, and wind turbine manufacturing means a different set of challenges. Typical solutions for large scale problems often involve installing robots on a rail system, but these building and installation configurations often turn these solutions into other puzzling problems. Moreover, it is often expensive and inaccurate.
Another solution would be to use a mobile platform to move the robot around the manufacturing plant. Some research is now being done to create an industrial solution for this issue.
As an example, the Southwest Research Institute (SwRI) has been developing large-scale robotic systems to paint fighter aircraft. They have been working on this application for 25 years. Over the years, there has been a growing need to automate this process for commercial and cargo aircraft. Scaling up their robot would be too expensive, so they decided to use a mobile robot.
They integrated a Vetex mobile platform with a Motoman robot arm (SIA-20) and a Nikon metrology iGPS device to create an off-the-shelf manipulator, Mr. Roam. Mr. Roam stands for Metrology Referenced Roving Accurate Manipulator. The metrology system is used to allow measurements and tracking of multiple objects in a large workspace with accuracy and in real-time.
SwRI conducted an experiment on an aircraft wing model and they prove the industrial application of their system. Their robot was able to auto-generate a path plan based on known 3-D geometry and registered data. Using the metrology technology, they were able to reproduce the path to within about 0.5/inch of precision on a wing model, which is good for painting applications.
The Institute is pursuing their research to improve the accuracy of this system. Using an inertial sensor, they expect to have accuracies of better than 1 mm.
There are a lot of potential applications for the SwRI’s mobile manipulator robot such as:
Assembly of large parts (wind turbine blade or tower)
Surface processing of large components such as a plane or ship (painting, sanding, inspection)
Welding large pieces
Decontaminating surfaces or areas (nuclear, biological or chemical)
Rapid prototyping
The Vetex mobile platform has a special feature. It has four omni-directional wheels. Each wheel has its own motor, brake and controller. By different combinations of the wheels' movements, the platform can move in any direction, even in limited space.
Vetex demonstrated their new platform at ProMat 2013 with the Motoman 7-axis arm (SIA-20) and Robotiq's 3-Finger Adaptive Robot Gripper. See the video.
For more information : SwRI’s research