Automated Coatings
Removal System
Robotics & Automation Engineering

image of the system to accommodate large components, to recycle the blast media.

The system is designed to accommodate large components, and is self-contained to recycle the blast media.

image of the Automated Coatings Removal System at a USAF maintenance facility.

This Automated Coatings Removal System is in operation at a USAF maintenance facility. View the video.

image of Automated Coatings Removal System control panel

Automated Coatings Removal System control panel

The Automated Coatings Removal System (ACRES) is a custom robotic system developed by Southwest Research Institute (SwRI) to automatically remove paint from large aircraft components in a manner that is safe, efficient, and cost effective.

Automated Coatings Removal System Background

Applying and removing coatings on military aircraft has become increasingly complicated by the widespread adoption of airframes with lightweight, fragile composite materials alongside traditional aluminum alloys, as well as the use of complex curves to maximize performance and minimize radar reflection.

Environmental, safety, and ergonomic requirements have gained importance. However, much of the depainting of aircraft and aircraft components is still being performed either through labor-intensive manual blasting or chemical stripping. The U.S. Air Force is working proactively to implement processes that are more cost-effective and that reduce the hazardous waste stream and prevent occupational injuries.

The challenge was to create a reliable, robotic depainting system to remove paint quickly and efficiently from a variety of aircraft components (wings, flaps, rudders, etc.) without damaging the underlying substrates.

The Custom Robotic Solution

The Automated Coatings Removal System has four major subsystems:

  • Media blast
  • Robotic automation
  • Component support and fixturing
  • Component preparation and handling

This Automated Coatings Removal System is in operation at a USAF maintenance facility. View Video in Windows Media.

Media Blast System

The blast subsystem includes a self-contained blast booth that uses a negative-pressure ventilation system and an operator control room. As is typical with many blast systems, the used media is recirculated through a floor recovery system and routed through a series of separators that remove broken-down media as well as ferrous and non-ferrous contaminants, including paint residue. Both new and cleaned media are transported to pressurized blast pots and metered through blast hoses to the nozzles at the robot's end-effector.

Automation System

The Automated Coatings Removal System robot is supported by an overhead gantry structure that allows its manipulator to move around the aircraft components from above. The overhead system is a combination of custom and commercial off-the-shelf (COTS) technologies. A FANUC Robotics manipulator with five degrees of freedom is the primary workhorse. SwRI engineers designed an additional three degrees of freedom to move the entire FANUC manipulator in three-dimensional space. The robot end-effector comprises an array of three flat, or "fan," nozzles that project the media at high velocity onto the aircraft substrate, stripping about a 9-inch swath. The end-effector also has a built-in camera that allows the operator in the control room to see the strip zone from the perspective of the end-effector.

Support and Fixturing System

Although the Automated Coatings Removal System can be programmed to depaint any component that fits within its large work envelope, the system will be initially preconfigured to depaint 27 off-airframe components, including:

  • A-10 rudders, elevators, inboard flaps, outboard flaps, decelerons, outer wings, and inner wing
  • F-16 horizontal stabilizers, flaperon, leading edge, and wings
  • C-130 ailerons, elevators, rudder, and floor panels

The system takes advantage of absolute positioning by using a universal component support chassis that will affix each component in a repeatable position.

Preparation and Handling System

The system includes a staging area outside the blast booth where components are prepared for blasting. This work includes masking areas that are not to be stripped and sealing all critical seams against media ingress. Support stands, similar to those used on the chassis, are replicated in the prep area. Due to very limiting space constraints and the need to protect aircraft components from damage, SwRI engineers developed effective procedures and handling tools to transfer parts into and out of the staging area.

Results/Outcome of the Automated Coatings Removal System

The Automated Coatings Removal System is enabling the Air Force to depaint off-airframe components more efficiently and effectively. The system will provide better consistency of the depaint process, reduce manpower and cost, and remove the operator from a potentially unsafe work environment.

The system is designed to use a new blast media, known as GPX, which has several advantages over the commonly used acrylic plastic media. With its cornstarch-based chemical matrix, it is less aggressive for sensitive substrates such as composites and thin-skinned aluminum, and it is also biodegradable. This more environmentally friendly media will result in additional savings to the government because of a smaller hazardous waste stream.

Related Terminology

robotic depainting system  •  noncontact inspection  • manufacturing systems  •  automation engineering  •  automatic paint removal  •  automated coatings removal system  •  aircraft depainting

Benefiting government, industry and the public through innovative science and technology
Southwest Research Institute® (SwRI®), headquartered in San Antonio, Texas, is a multidisciplinary, independent, nonprofit, applied engineering and physical sciences research and development organization with 9 technical divisions.