P06004: Air Surveillance Platform for CIS
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Imaging Payload

Table of Contents

One aspect of this design project involved building an imaging payload, which was to be mounted in the plane. The research and development of the imaging payload was based on three qualities: flexibility, stability, and complexity.

Components

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The components for the payload were chosen with simplicity and compatibility in mind. Standardized interfaces were chosen because of the ease of use and ability to find replacement or alternate parts. The camera utilizes a Camera Link connection, which is one of the most common camera interfaces available. Many manufacturers offer cameras using this connection. In addition, the camera lens chosen allows the addition of a filter in the future. The computer is a PC104 embedded computer, which communicates to the frame grabber board over a quite common PC104 bus.

Software Design

The software design was slowed down due to the amount of time it took to receive the frame grabber and the API associated with it. While waiting for the last component, a software design concept was generated and a library named Image Magick was chosen to handle the image manipulation. The code was designed to read data from the plane, and alter the image capture rate to produce a 40% overlap.

The time constraints created by the slow delivery of the frame grabber forced some modification to the code design. It currently relies on user input to specify how many pictures will be taken, and adjustment of the delay between images. It currently defaults to a 10 image spread at approximately one image every four seconds.

End Result

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As a result of the careful design and development, a working imaging payload was developed and is ready for mounting into a plane. Currently the code is very simple, but still very functional.

Testing of the payload was done under laboratory conditions, including taking a large series of images. These images were automatically saved to disk by the Image Magick library into a common JPEG format.

Future Work

As with just about everything, there is room for future improvement in the imaging payload. Due to the set-backs with the plane, it was never mounted and tested in flight. In addition, the software can be improved by cleaning up existing code. The original design concept called for an interface with the AP50 autopilot board to read data and calculate the image capture rate, but this was never implemented. The software may also benefit from a division of control logic and image capture function. This could be done to allow a fixed rate or dynamic rate capture with little user effort.