Three-corner Satellite Imaging Systems Presented by: Ryan Olds Matt Culbreth Matt Gadda

The Three-Corner Satellite Project  Schools Participating:  CU – EEDS and Imaging  ASU – Structures and Power Systems  NMSU – Radio Systems  Mission Objectives  Acquiring Stereoscopic Images of Earth  Inter-Satellite Communications  Automated Mission Operations

Objectives of the Imaging System  Acquiring Stereoscopic Images of Earth:  Using a Formation of Three Satellites to take coordinated pictures of Earth.  Software will be used to analyze pictures taken and use them to determine the height of objects on Earth.

Camera Equipment Used  JamCam 2.0  Developed by KBGear  Advantages:  Very easy to obtain.  Knowledge of the product and resources available on the product.  Space Worthy.  Disadvantages:  Relatively low quality.

JamCam Test Image

Automated Picture Taking  Step 1: Turn on the Camera and verify it is responding to commands.  Step 2: Clear the camera memory banks.  Step 3: Take a picture.  Step 4: Download the picture from the camera memory to the flight computer memory.  Step 5: Process the image.  Step 6: Power down the camera equipment.  Step 7: Downlink the image to the ground station on the next available pass.

Image Processing  RGB Interpolation:  Averaging routine to transform an 8-bit color image to a 24-bit color image. 8-bit Pixel Color Pattern Needed green value Needed blue value

8-bit Color  24-bit Color 8-bit Color24-bit Color

Image Processing  JPEG Compression:  Advantages:  Can achieve 20:1 compression with good picture quality  Very well supported by software  Programming libraries available  Disadvantages:  “Lossy” compression  Visual artifacts present at high compression ratios  Poor quality when compression high-contrast images

JPEG Compression, Quality = 100%

JPEG Compression, Quality = 10%

Determining Object Height Height is determined through the equation: h = WD(d 1 – d 2 )/S

Determining Object Height Using similar triangles, the height equation is easily derived.

Useful Applications  Weather Information for Meteorologists.  Determining Cloud Height.  Surveillance.  Inter-Planetary Exploration.

Summary  The Objectives for the imaging system are to acquire stereoscopic images of Earth, and to use these pictures to determine object height on Earth.  To accomplish this mission, our team will be using JamCam 2.0 camera equipment, converting the pictures it takes to JPEG files, and transmitting them back to Earth to be analyzed.

References  1)Russ, John C. The Image Processing Handbook. London: CRC Press,  2)Pennebaker, W.B. Jpeg: Still Image Data Compression Standard. New York: Van Nostrand Reinhold, Acknowledgements: Thanks to: Brian Egaas for provided his resources and knowledge of stereo imaging as well as his experimental results for determining object dimensions from stereo images. Mike Walters for providing experimental results and pictures of his work on determining object dimensions from stereo images.

Questions?