BalloonSat
From Wikipedia, the free encyclopedia
A BalloonSat is a simple package designed to carry lightweight experiments into near space. They are popular as an introduction to engineering principles in some high school and college courses. BalloonSats are carried a secondary payloads on ARHAB flights. One reason BalloonSats are simple is because they require the inclusion of tracking equipment; as secondary payloads, they already are being carried by tracking capsules.
Often the design of a BalloonSat is under weight and volume constraints. This encourages good engineering practices, introduces a challenge, and allows for the inclusion of many BalloonSats on an ARHAB flight. The airframe material is almost always Styrofoam or Foamcore, as they are light weight, easy to machine, and provide reasonably good insulation.
Most carry H8 Hobo data loggers (manuafactered by OnSet Computing) and APS cameras operated by 555 timer circuits. Popular sensors for the Hobo datalogger include air temperature and relative humidity. OnSet's new Pendant G is another popular sensor, but that doesn't require a Hobo datalogger. With the rise of digital cameras, more of the APS cameras are beign replaced. Additional experiments typcially carried inside BalloonSats included captive insects and food items.
Before launch, most BalloonSats are required to undergo testing. These tests are desgined to insure the BalloonSat will function properly and return science results. The tests include a cold soak, drop test, function test, and weighing. The cold soak test simualtes some of the intensely cold temperatures the BalooonSat will experience during its misison. A launch and landing can be tramatic, therefore the drop test requires the BalloonSat hold together and still function after an abrupt drop. The function test verifies the BalloonSat crew can prep the BalloonSat at the launch site.
