Releasing the Raptor with Robots

Innovation in automation leads to a faster, more uniform paint finish

9 Ratings

Imagine you're completely covered in a hot Tyvek suit, wearing a paint mask, and lying in a cramped aircraft duct holding a tangle of hoses connected to a paint gun. You roll back and forth from your back, to your side, and then onto your knees in a crouched position, supporting yourself with an elbow, while trying to spray coatings at a consistent, repeatable thickness — now do it all day long, day after day.


Currently, aircraft engine inlet coatings are sprayed manually when being restored at the depot. This process requires an operator to climb into a confined space carrying all necessary equipment and supply lines while donning a significant amount of personal protective equipment (PPE). A significant number of hazards exist for workers in these conditions, and applying a precise coating is incredibly challenging. Can an automated robotic system apply the coatings in the assembled aircraft inlets, which have complex-contoured geometries, in a safer, more efficient, and more accurate manner than a manual process?


The Air Force requires an efficient way to repair coatings on the inlets of the F-22 fleet so they can get aircraft back in service as quickly as possible. The existing repair process is time consuming as a manual operator is forced to continually change body positions while sliding around inside the duct, only able to process a small section at a time. In addition, a variety of ergonomic and health hazards exist for personnel having to work in a confined space with excessive over-spray. As a result, the application of difficult performance coatings is inconsistent, varying from person to person, and requires non-value added re-work to meet mission requirements.


Aerobotix worked with Lockheed Martin, AFRL and Hill AFB engineers to develop modified FANUC robots capable of coating the confines of the F-22 inlets. The team used historical production data and knowledge gained from key F-22 personnel to duplicate process parameters utilized when the midbody was sprayed in production. Aerobotix also applied current-state methodologies, such as mobile rails, derived from other inlet coating projects to reduce risk and cost to these F-22 systems.

"The robots are able to spray several of the coatings in half the time versus manual spraying" — Bret Benvenuti


During initial F-22 production, the inlets were painted as a stand-alone subsection called the mid-body, but now they have to be painted as part of the full body aircraft. There are a number of added parts and aircraft structure that present a challenge to the automation. In order to fit inside of the tight confines around the aircraft, robots had to be modified to reduce their overall footprint. Also, special carbon fiber tubes had to be made to enable the robots to articulate the spray gun in the aft end of the inlet as well as the forward end of the aircraft. The design of the tubes had to be light enough for automated manipulation yet rigid enough not to sag and start bouncing. Special attention was applied to the programming so as not to induce bounce or vibration along the spray path. The forward and aft robots take turns spraying in the aft end, then the forward end of the inlet as the entire duct cannot be reached from either end. The intersection where the front and aft robot’s paths intersect was “painstakingly” programmed to create an even transition of coating from front to back. To reduce the need for two robots in the front and two robots in the rear, Aerobotix designed special rails that are manually floated on integrated air bearings, from the left side of the aircraft to the right side of the aircraft reducing cost and complexity. The robots move in and out of the ducts, by way of a coordinated 7th axis linear rail designed with over-spray protection.


The new robots take people out of a confined space and harsh environment as well as speeds the F-22 back into service in half the time compared to manually spraying the coatings.

This project allowed our company to stretch our thinking and way of designing systems, enabling us to apply new concepts to other defense related projects.

Aerobotix, inc.

Madison, AL

As a FANUC Authorized Integrator, we specialize in providing turn-key robotic coating systems for aerospace, military, NASA, and general industrial applications, providing a range of solutions for robotic and automated coating needs ranging from single robots to complex multi-robot systems.

Nathan  Morgan Nathan  Morgan

Nathan Morgan

Process Technician

Erik Garay Erik Garay

Erik Garay

Controls Engineer

Bret Benvenuti Bret Benvenuti

Bret Benvenuti

Robot Engineer


Automated Aircraft Inlet Coating





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