Fain Models (Bedford, TX) uses the HandHeld laser scanner from NVision (Wixom, MI) to produce copies of jet fighter ejection seats for use in flight simulation and training for significantly less than the cost of a flight-worthy seat. Fain technicians use the NVision scanner to capture 3-D geometry of the more than 100 components in the seat, using the geometry to machine the seats or models used to make molds.
“The NVision HandHeld scanner is ideal for this application because it can freely move around an object to capture data at any angle at a very high resolution,” says Cris Runge, scanning and reverse engineering manager for Fain Models.
Because of the high cost and risks involved with training in actual aircraft, the military is moving as much training as possible to simulators that realistically duplicate the flying experience. The companies that make flight simulators need high-fidelity ejection seats that look, feel and function like the original seats but do not require ejection hardware and other internal components. It typically costs $150,000 to $300,000 to buy real fighter aircraft seats from the original equipment manufacturers in small quantities.
Fain Models has developed a method to produce the seats for a much lower cost of only $15,000 to $75,000 per seat, or one-tenth to one-fourth of the cost of an actual seat. The company disassembles a real seat and places the components on a granite base. The technician then moves the NVision HandHeld scanner around the seat to capture its complete geometry. A key advantage of the NVision HandHeld Scanner is that it is mounted on a mechanical arm so it can move freely around parts of any size. The mechanical arm keeps track of the scanner’s location so all data is collected within the same coordinate system.
The NVision scanner generates a point cloud consisting of the coordinates of individual points. Fain technicians use software that comes with the scanner to convert the point cloud to a polygon mesh. Then they use reverse engineering software to convert the polygon data to a surface model. They export the surface model in the IGES or STEP format and import it into their computer-aided design (CAD) software. The model is then fine-tuned and toolpaths are created for machining. Most of the seat is machined directly from aluminum. The plastic parts that the pilot directly interfaces with are produced with vacuum tools, created from scanned data as well.
“Our method enables us to manufacture a complete seat months faster, when compared to traditional methods, depending on the level of fidelity required,” says Runge. “This makes it possible for us to offer large savings to companies that build simulators. A key to our method’s success is that the NVision HandHeld scanner is able to quickly reverse engineer complicated parts at a high level of accuracy.”