Wright State University High Altitude Balloon Team - Our lab is at 100,000 feet
2008-2009
From HABTWiki
Contents
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Summary
Launches
Launch 7 (4-1)- October 18, 2008
This launch went fairly well but had a few glitches that led to a rather interesting recovery. Two things led to the recovery in Daniel Boone National Forest: The balloon was under-inflated and the winds changed. Had the balloon been inflated at the correct amount, the shifted winds would have dropped our balloon through CVG's airspace. This would have been an unfortunate occurrence if the FAA wished to pursue it. Thankfully, we had a really slow ascent rate and flew over and well clear of Cincinnati's airspace. The new bag deployment system for the balloon worked great, the only hitch being the under-inflation of the balloon. This was not a big failure; the inflation was close enough so that the balloon was able to lift the package, as opposed to the first few filling attempts during our July 2008 launch.
This was the first launch with the new team of students for the 2008-2009 school year. Pilots have a saying, "Any landing you can walk away from is a good one, and any landing where you can use the aircraft afterward is an excellent one." This launch was kind of like the latter. Everything worked well and the system was recovered. Mistakes were made and things were learned. This was a good first launch. It has shown us that there is a need for an improved launch-day checklist. Our vulnerability to a shift in wind that can easily carry the balloon into the graces of the FAA suggests that we make a cut-down system our top priority.
I would like to add a thank you to Justin Munger (W1IX), who drove from Columbus and tracked our balloon all the way to its landing point in Kentucky. His assistance was most appreciated. And a Special Thanks should go to Ray Abney, the owner of the property we landed in. He went above and beyond (with a chainsaw) to assist us in our recovery efforts on his property. N Baine 19:44, 20 October 2008 (EDT)
Pictures from the launch/recovery.
A brief video summarizing this launch may be found here: Launch 1
More details are forthcoming.
Launch 8 (4-2) - January 4, 2009
Details for this section are forthcoming...
Pictures from the launch.
Launch 2 video: Launch 2
Pictures from the recovery.
Launch 9 (4-3) - February 24, 2009
40° 8'40.20"N, 83°33'43.80"W
Pictures from the launch
Launch 9 videos
Launch 9 Bottom Payload Part 1
Launch 9 Bottom Payload Part 2
Launch 10 (4-4)- April 4, 2009
Still Photos
Still pictures grabbed from the on-board video
Videos
Release of balloon and payload.
Flight Highlights: (wmv format) (avi format) (flash format)
Balloon Burst - Slow Motion: (wmf format) (avi format) (flash format)
First ever video of one of our balloons returning to earth.
Launch 11 (4-5)- May 9, 2009
Still Photos
Pictures from the launch and recovery sites
Videos
Launch: (wmv format) (avi format) (flash format)
Camera 1 Video 1: [1]
Launch 12 (4-6) - June 23, 2009
Flight assessment of Launch 12
Top Payload: The NiCr cut-down from the balloon was severed and the metal connecting ring supported the payloads during flight. Originally, the payloads were supported by the NiCr wire which is thought to have broken under the stress of impact loading from take off or it is possible the wire broke during flight due to the extreme temperature drop making it brittle and more susceptible to failure. This failure rules out the use of NiCr being used as a single connection point between the balloon and payloads. However using a non-metal ring coupled with the NiCr is a possible implementation.
Bottom Payload: Upon receiving the payload it was found that the blue NiCr cut down circuit board would not power up in the ‘as received’ condition. It was confirmed by the CEG’s that there was a signal sent from the wildfire board to deploy the parachute at approximately 63,000 feet. A further analysis was done on the NiCr cut down board and two cables were found disconnected from the bottom of the circuit board. This caused the switch not to have its power source and would not allow for cut down. This could have been caused during the installation of a sticky back Velcro attachment to the bottom of the circuit board or during the initial launch sequence. New NiCr boards have been made and will replace the existing boards. Prior to the next launch it is recommended that two independent NiCr cut down systems be implemented on the parachute release for the free-fall vehicle. Also full system test is recommended with signaled cut-downs.
Still Photos
Pictures from the launch and recovery sites
Video
Flight: (wmv format) (flash format)
Experiments
Release Mechanism Testing
After the October 18, 2008 launch it became obvious to the team that a method of releasing the payload from the balloon was vital to future operations. A release mechanism was already underway and development was continued. Two methods were employed -- nichrome wire to burn the cord and a servo mechanism to relase the cord. The systems were thoroughly tested in cold and vacuum environments in order to better understand how they will work in flight.
A short video of both systems may be seen here: Release Sequence
This video several prototype nichrome release systems being tested. The popping wire utilized a capacitor to dump current through the wire while the slower burning wire utilized two D batteries and an actuator. A lighter weight/safer system is currently under development by Bruce Rahn. The servo release is shown next dropping a 12 lb weight followed by a clip of the payload dropping as it would during flight. C Barnes 9:49, 5 February 2009 (EDT)
Parachute Deployment System Testing
A parachute deployment system was also tested for use in a future payload system. Several means of deployment were investigated including a spring ejection, C02 gas expansion, gunpowder charges, and ram air deployment. The most feasible system for use in high altitudes was decided to be gunpowder charges. The high energy density in gunpowder combustion allowed for a light weight deployment system. The lack of moving parts allows for fewer components to be affected by cold. The only concern was with combustion in a near vacuum environment. A gunpowder charge system was developed and tested under multiple conditions and environments including high winds and vacuums. A video sequence of the deployment system testing is coming soon. C Barnes 15:18, 5 February 2009 (EDT)
Launch Simulation System Testing
After multiple component failures in the payload rigging during the January 4, 2009 launch, measures were taken to improve the integrity of the payload connections. These measures included piece-by-piece strength testing and system testing using a launch simulator. The system test is composed of a pulley system mounted on a campus bridge. The complete payload is connected to one end of the line and a 30lb sand bag is connected to the other side of the line. The pulleys are spread apart enough to prevent contact between the payload and the weight.
The line connecting the payload to the cord is allowed to be slack to simulate the initial snap during takeoff. The weight is then dropped and the payload system is violently jolted from the ground. This test is capable of proving connection integrity or finding weak components before launch day.
The first test using this system was performed on February 3, 2009 which resulted in three fishing leader connections snapping. The payload was still securely fastened, but the failure was investigated. All three lines were found to have snapped in the same section of rigging. Springs were attached to the ends of these lines and the snaps at each end of the line were upgraded with heavier snaps. The springs were connected to the leaders in parallel with backup cords. In the case a spring should fail the connection is not broken.
The upgraded system was tested again on February 5, 2009. The violent take-off of the system proved to be no match for the newly beefed-up connections and shock absorbing springs/elastic bands. This system may be viewed in action in the following video. C Barnes 9:49, 5 February 2009 (EDT)
Video of the February 5, 2009 launch simulation: Launch Simulation 1
Pictures from the first round of launch simulation
Pictures from the second round of launch simulation
Major Developments
Presentations
Computer Engineering
Electrical Engineering
- Video Team (Falknor, Guenther, Kelly)
Project Introduction | Design Review | Progress Review | Midterm Review | Final
- Power Bus Team (Aoun Barki, Henok Feseha, Todd Rogers)
Project Introduction | Design Review | Progress Review | Midterm Review | Final
- Telemetry and Remote Control Team (Crowdy, Overmyer)
Project Introduction | Design Review | Progress Review| Midterm Review
Mechanical Engineering
- Team 1
Team Members
Team members consist of:
Senior Design Students
Caleb Barnes, Nathaniel Herrmann and Michelle Wilson - Mechanical Engineering, Fall 2008/Winter 2009
Shawn Zackey, Jack Snyder and Ryan Heskett - Mechanical Engineering, Winter 2009/Spring 2009
Mark Falknor, Brent Guenther, and Adam Kelly- Electrical Engineering, Fall 2008/Winter 2009
Ryan Back, Jon Baumann, and Michael Walters - Computer Engineering, Winter 2009/Spring 2009
Andrew Crowdy, Steve Overmyer, Aoun Barki, Todd Rogers, and Henok Feseha- Electrical Engineering, Winter 2009/Spring 2009
Graduate Students
Nicholas Baine - EE 2007
Daniel Rahn - EE 2008
Other
Advisors
Ruby Mawasha - Mechanical and Materials Engineering, Joseph C. Slater - Mechanical and Materials Engineering, J. Mitch Wolff - Mechanical and Materials Engineering, John Wu - Electrical Engineering, Stephen Mascarella - Mechanical and Materials Engineering, Brandon Kirby - Cornerstone Research Group, Bruce Rahn - Electrical Engineering mentor
