Satellite Solar Cell Reflector Scanning Application
using the EOIS Mini-Moiré Sensor

EOIS recently assisted a customer who needed to inspect reflector panels designed to reflect sunlight onto satellite solar cells. The customer needed to insure that waves or "wrinkles" in the mylar panels did not act as a lens, concentrating too much sunlight and overheating the solar cells. Since the material was flexible, a non-contact sensor was required.

We used our Mini-Moiré sensor with a portable FaroArm® (see below), so we could travel to the customer site to perform the inspection. We scanned three reflector panels in less than two days. Each panel was 3.5 meters high by 2 meters wide, and had to be mounted vertically in order to minimize the effect of gravity. Because of the light weight of the FaroArm and EOIS sensor, we were able to raise and lower the scanner on a tripod, to scan the full height of the panel.

We scanned the 4 quadrants of the panel separately, and then aligned the results using reference points on the panel mounting frame. A total of 28 million points were measured on each panel. A reduced set of data points for one panel is shown below.

The point data was reduced to 70K points and organized into a 10mm x 10mm grid. The rendered image of this data below clearly shows the wrinkles in the panel.

The Mini-Moiré was ideally suited for this application, since it can scan a large area quickly, and still produce very high resolution data. The MMW.10 Mini-Moiré sensor captures an area of 250mm x 250mm in a single image, and can produce up to 300K points for each image.

The combination of the Mini-Moiré sensor and the FaroArm has proven to be a very flexible tool. It is portable and rugged enough to travel to most work sites, and the 6 rotation axes of the arm allow it to to scan even the most complex shapes.