Demosat III Final Report

DemoSat III Final Report

Team Solitary

The goal of team Solitary is to develop a basic understanding of challenges involved with imaging in the upper atmosphere.

Derek Bonner

Dr. Matt Semak, Dr. Robert Walch, Dr. Cynthia Galovich

University of Northern Colorado Colorado Space Grant Consortium

August 8, 2005

University of Northern Colorado - 1 - August 8, 2005 Colorado Space Grant Consortium 1.0 Mission Statement The goal of VideoSat is to obtain basic video and still images of the flight of the DemoSat III. The primary objective is to have a video record of the balloon burst. The secondary objective of the mission is to obtain digital still images as seen from the bottom of the payload. Through construction of the payload one expects to learn how to design and build simple circuitry. The exploration and evaluation of different methods for recording images and video at high altitudes will also be a key learning objective.

2.0 Mission Requirements and Description Functional design of the payload included two parts. The first of the two parts was to obtain video using a digital camera that recorded on a medium that had no moving parts. This simplifying requirement was to prevent the loss of data during flight due to any mechanical error. The second design requirement was to find the simplest and most economical method for taking digital still photos. Emphasizing a digital for allows one to eventually condenser the transfer of data in real time to a ground station. The top design requirement was to minimize the weight of the payload. This restriction was put in place to allow future payload constructions to use components that worked properly saving time and research while opening the weight budget for equipment that may be added later. This would then allow for a focus on other aspects of the project design. Since there was a strict time limit for this project the simplest design ideas were implemented throughout the majority of the construction. At the completion of the flight two forms of data will be extracted and analyzed. A video approximately two hours in length will be taken from the video camera to ensure that the balloon burst was captured. 1.3Megapixel still photos of the ground below will be taken at one minute increments.

3.0 Payload Design The design of the VideoSat payload begins with the choice of what type of container to house the project in. To properly mount the two cameras the container need to have flat sides so the cameras would be flush. For the container’s outer shell sturdy foam core was seen as the best material. Foam core is light weight and durable providing easy modification for the necessary holes to be cut for the cameras. The foam core was then lined with aluminum tape inside and out to provide insulation. The next layer in the box was a foam insulation wrapped in a space blanket to provide further insulation. The reasons two layers of insulation were twofold. The first reason was to prevent leakage of heat provided by the electric heater circuit. The second reason was to provide a cushion for the balsa wood frame to sit on so that it would not shift and break. Between the foam core and foam insulation two square pieces of transparency film were attached. The reason for this was to make sure that heat was contained in the box while allowing the cameras to record data. The frame was constructed

University of Northern Colorado - 2 - August 8, 2005 Colorado Space Grant Consortium out of balsa wood given this product’s strong durability and light weight. Other materials such as aluminum tubing and steel tubing were considered but were dismissed because of their heavier weights and the complexity of assembly. To assemble the frame four squares were constructed for the top, bottom, and two sides of the payload. These frames had box joints at each corner so that they would create a strong bond. A wood epoxy was used to bond the squares. Once the four sides of the frame were completed they were placed in the box and then bonded together with wood epoxy creating a strong frame in which to mount the components.

Figure 1 - Payload frame with circuitry, battery, and still camera mounted.

The first component to be mounted was the heater circuit with battery box. The battery box which was to hold three 9-volt batteries was made from a balsa wood sheet and bonded using wood glue. A cross brace was mounted on the side of the frame and the battery box was glued on top of that. The heater resistors were placed at the bottom of the box on the frame as to allow the hot air to rise, creating a convection current in the box. The Dakota Digital still camera was then mounted on the bottom of the frame. The still camera was wired to a 555 timer circuit and to the power switch on the outside of the box. The 555 timer circuit (Figure 2) was chosen for its simple design to trigger the still camera to take a picture approximately ever minute.

University of Northern Colorado - 3 - August 8, 2005 Colorado Space Grant Consortium Figure 2 – 555 TimerCircuit Schematic

The final component to be installed was the video camera. The choice of which camera to use was a major factor. The camera needed to be powered for at least two hours while recording video. The selection of recording medium narrowed the choices of which video camera to use. The Premier MDV-3 camera was chosen for its long battery life and ability to write to a SD memory card. This camera was placed in a wire cage with thin insulation. The caged camera was then tied down to a section of balsa wood mounted on the cross brace. The need for the cage was to make sure that the camera would not move during flight resulting in an obstruction of the video.

Mass Budget Cost Budget Video camera w/cage 235g Video camera $150 Still camera 105g Still camera $10.99 Balsa wood frame 87g Balsa wood $7.50 Box 345g 4x AA batteries $12 Brass rod 50g Bonding agents $14 3x 9V batteries 75g 1GB SD card $56 Dryrite 5g Balsa wood $7.50 Circuitry 25g Miscellaneous ~$20 Miscellaneous 78g

Total 1005g Total ~$277.99

4.0 Student Involvement Student Derek Bonner – Physics Major with Engineering Emphasis

Advising Dr. Matt Semak Dr. Robert Walch Dr. Cynthia Galovich Kenneth Walter

University of Northern Colorado - 4 - August 8, 2005 Colorado Space Grant Consortium 5.0 Testing Results Each component was tested separately, and there was one test that included all components except the digital still camera. These tests included a drop test on the box, heater circuit test, still camera circuit test, and video camera test. The digital still camera was not included in the final test due to the fact pictures would not be able to be cleared from the memory while mounted in the box. The drop test showed that box was able to take the impact if dropped from a height of ten feet. However, this test introduced the problem of properly mounting the cameras so that they would not shift from their intended positions, obscuring their view. The heater circuit test was designed to determine if the six resistors would generate heat when the switch on the outside of the box was turned on. The results of the test showed that no improvement would be needed on this circuit. The still camera circuit needed the most testing of any component. This circuit was first built on the protoboard and wires were then be connected to a test camera see if the circuit properly functioned when powered by the camera’s battery. Pictures were successfully taken. The circuit was then soldiered into a permanent board and tested again using its power switch that was to be mounted on the outside of the box. Results of this test showed that the camera should take still pictures in conditions, at least, similar to those at launch. The final and simplest test was to see how long the selected video camera would be able to take video, and if it would properly save the video to the memory. The camera was set to record and left on a table for two hours and forty-five minutes. When checked the memory card was full and the camera had shut off. The video was then tested to see if it would be able to be downloaded to a computer to check for corruption of the file. There was no corruption of the file. It was shown that with new batteries and a empty 1GB memory card a video could be recorded for two hours and twenty-one minutes and would be able to be successfully retrieved at a later time.

6.0 Mission Results When the recovery site was reached, the box was intact without any holes or dents on the outer part of the box. The brass pole that ran vertically through the box was bent on the top of the box from the landing. This was determined by analyzing the video. When the zip ties that held the box together were cut and the box was opened the electric heater was checked to see if it was still generating heat and it, in fact, was. All the components were checked to see if they had shifted during flight. All components had remained in their original positions.

Upon examination of video and pictures produced by the cameras the following results were obtained. The video recorded for the entire predicted time of two hours and twenty-one minutes. Approximately one hour and fifty-four minutes into the flight the balloon burst and the parachute was deployed. This section of the video was blurred from what seemed to be condensation that had built up earlier on the flight. Still, this video was visible. The “condensation”

University of Northern Colorado - 5 - August 8, 2005 Colorado Space Grant Consortium formed on the transparency film possibly due to the temperature difference between the outside of the box and the air outside. An additional factor of having gone through clouds could also contribute to the blurred video because there was no way for the “condensation” to sheet off of the film. The digital still camera did not take any pictures during the flight. The reason for this is believed to be a short in the wiring that connected the switch to the power supply of the camera. The payload performed the primary objective of the flight - capturing the balloon burst (Figure 3).

Figure 3 – Still images taken from video of the balloon burst and parachute deployment

7.0 Conclusions After reviewing the results of the flight, many conclusions can be made about the effectiveness of the experimental design. The foam core outer shell proved to be able to withstand the impact when landing while providing insulation for the equipment. The foam insulation lined with the space blanket contained the heat necessary to keep the equipment functioning in lower temperatures and ensured that the balsa wood frame did not shift during flight. The insulation preformed so well that the box may have been too warm and created the difference in temperature that may have caused the “condensation” to form on the transparency. The balsa wood frame showed no signs of cracks or loose joints

University of Northern Colorado - 6 - August 8, 2005 Colorado Space Grant Consortium and met all expectations set during construction. Mounting for all components were stable at the time of recovery. The fact that the box rotated around the string was predicted to cause blurring of images and video but actually helped in taking video. The rotation allowed the camera’s view to change during flight, sometimes escaping sunlight which blinded the video camera. The only unknown in the experiment is if the still camera would have taken pictures without being obscured by parts of the box. Since the primary objective was completed the mission was considered a success and will offer others that wish to follow a firm basis on which to improve the experiment.

8.0 Potential Follow-on Work If this mission were to continue there would be many improvements that could be made to the design.

These improvements include:  A higher capacity SD memory card to capture higher quality video of the flight and balloon burst  A method for preventing “condensation” from forming  More cameras with different orientations on the payload  Real time transmission of data to a ground station  Adding an altimeter to see what visible changes exist at what altitudes  Pressure and temperature sensors both inside and outside of the container  Error logging for equipment to pinpoint problems during flight  Lights on the outside of the box that will indicate if the equipment inside is properly functioning

9.0 Benefits to NASA and Scientific Community This mission would be valuable to future work for NASA in planetary landings. The use of different methods of using visual media will help in locating obstacles that may exist in landings. The mapping of terrain can help design teams to predict the best design for rovers to complete their mission.

In unmanned exploration, high resolution visual feedback transmitted over great distances is desired. VideoSat provides a foundation for this goal. Miniaturization of equipment and improvement of data quality can be expanded given the lessons learned from this simple experiment. It also leaves room for the development of a transfer system from the recording equipment to a ground station. This mission will also help expand surveillance technology that may help with issues that require visual data. In the recent space shuttle launch it was video that provided the necessary information for NASA officials to determine what damage the debris may have caused. A better understanding of what environmental variables affect recording instruments during a launch would prove very valuable for monitoring the safety during a launch.

University of Northern Colorado - 7 - August 8, 2005 Colorado Space Grant Consortium 10.0 Lessons Learned While working on VideoSat many lessons were learned. The importance of brainstorming ideas about construction instead of using the first idea that came to mind was made apparent. The necessity of extreme testing of each component as well as the testing of these components when fully assembled. Concerning the failure of the digital still camera, it was quite apparent that there was a need for reliability. The still camera was added to the experiment more for the insight into what effects the temperatures and pressures of a high altitude would have on such devices. Adding fail-safes to help determine the problems with the equipment would offer invaluable information for subsequent attempts.

University of Northern Colorado - 8 - August 8, 2005 Colorado Space Grant Consortium