• CADed a chassis for the payload
  • 7.5x7x8' Cube-ish
  • 2 layers split by a divider plate
  • Balloon's 4 point harness attached to base plate, no top plate. Initially planned on mounting to a roof fixture, but changed to floor fixture because: a) it'd be redundant to have both a roof for the chassis and a roof of foam, and b) it'd make it hard to move things around and physically insert things with a roof in the way.
  • Foam was made out of insulation foam board, selected at 3/4" to protect the sensors.
    • 3/4" was chosen based on this guide for styrofoam: High Altitude Ballooning, From The Ground Up (and back again) – Dave Akerman

Improvements to be made 

• • Fix up timing next time and make sure to properly train everyone in CADing so a last minute grind doesn't need to be done again, and so that we have time to test, and play around with the physical model prior to launch
  • Get a better visual idea of how to budget space (i.e. allocating better clearance)
  • Account for battery drain during setup
  • Determine heat emitted of active components
• Important Factors
  • Dedicating enough space and surface area for all components. This determined the size of the cube and how many layers
  • The size of the biggest components, including the spectrometer and the muon detector; primary determiners in layout and setup
  • Weight - comply with regulations, minimize the size of spectrometer as it was being designed and built. We considered changing the 
  • Weight distribution - minimize spin as HAB ascended
  • Screw embedment length - impacted our decision for wall thickness
  • Thermodynamic regulation - foam was used to insulate the payload from high altitude temperatures. We concluded thermal emission from batteries weren't a problem. 
    • NOTE for later - Why were the batteries' thermal emissions not a problem anymore
  • Sensor Accessibility - some components needed to have access to the outside. The Go-Pro was integrated completely outside of the box. The spectrometer was part inside so sensitive electronics could be safe, and we led a fiber optic cable to the outside of the chassis by cutting a tiny hole in the foam.
• Other Ideas
  • Solid wall box
  • 3 Layers
• Cut Foam for temperature insulation
  • Everything was measured precisely and cut out in accordance

HAB Chassis Design Report 

Task: Design a chassis for a high-altitude balloon test. The design must protect the interior components from temperature fluctuations and environmental exposure. Some sensors had their own individual requirements when implemented in the chassis:

• The spectrometer's sensor must be exposed through one of the sides of the chassis, pointing upwards exposed to the sun.
• The Go-Pro must be secured on the outside of the chassis, pointed to the horizon.
• The second live camera must be exposed through one of the sides, pointing just under the horizon.

Additionally, the chassis must not exceed a total weight of 6 lbs (excluding the balloon) due to §101.1(a)(4)(ii) (Hard Limit 6 lbs/package - Hard per-package weight cap)