posted July 07, 2004 13:05            

Last month, www.cubesatkit.com's Adam Reif was present for the shake
test of our CubeSat Kit. Adam is responsible for the mechanical
design of the CubeSat Kit.

A standard 1U CubeSat Kit was used, along with a prototyping PCB in
Slot 1, an aluminum mass where Slots 2&3 are normally located, and a
test PCB in Slot 4. Results are as follows (pictures below):

*********

Test date: June 17, 2004

Facility: Raytheon Laboratory, Santa Barbara, CA

Test parameters: 125% of DNEPR launch profile

Test configuration: Skeletonized CubeSat Kit prepared to 980 grams (custom
ballast installed to attain weight, and provide neutral point of balance).
All fasteners were staked in place with epoxy. Three accelerometers placed on
CubeSatKit chassis. Unit was placed into a P-POD with two other 1U
CubeSat's (Montana & Hawaii).

Results: No mechanical failures apparent. Minor abrasion observed at "feet"
where they were in contact with the next CubeSat unit. Additionally, unit has
subsequently passed all of its normal electrical and functionality
tests without error.

*********

The unit tested represents the current production CubeSat Kit, of
which several are now in customer hands. We're still waiting for the
accelerometer and other data for a more thorough analysis.

For the shake test, we had two main areas of concern: 1) whether the
levers on the Remove-Before-Flight and Launch switches would remain
captured in place in the plastic bodies of the switches, and 2)
whether any tears in the sheet metal would occur at the bend reliefs
where the Chassis meets the cover plate. It turns out our fears were
unfounded, as the CubeSat Kit survived the shake test with flying
colors.

Pictures are described below:

The kit disassembled, with all of its parts for testing visible:
http://www.cubesatkit.com/image/vibe-test_pre-assembly.jpg. You can
see the FM430 Flight Module (black PCB), the Prototyping PCB (red),
the inter-slot connectors (they're standard 40-pin PC/104
stackthrough connectors), the 519g custom Aluminum mass, the MHX-2400
2.4GHz modem (with red dot on it), the test PCB (green), the Chassis,
Base Plate and Cover Plate, and various hardware and locking agents.

Building up the CubeSat Kit, with the FM430 Flight Module (black PCB)
in Slot 0, the MHX-2400 modem attached to it, and a prototyping PCB
in Slot 1: http://www.cubesatkit.com/image/vibe-test_slot1-assy1.jpg.
The entire PCB stack is attached to the Base Plate via threaded
standoffs. The switch in the foreground is the Launch switch. The
Remove-Before-Flight Switch is mounted horizontally on the FM430
Flight Module, behind the stainless RBF pin guide on the upright wall
of the Base Plate.

Completely built-up CubeSat Kit ready for shake test, with Aluminum
mass and test PCB added:
http://www.cubesatkit.com/image/vibe-test_slot4-assy1.jpg.
Accelerometers have also been added, and the Chassis is in place.
Just waiting for the Cover Plate.

The complete assembly, ready for test:
http://www.cubesatkit.com/image/vibe-test_ready-for-test2.jpg. A USB
cable is attached to power and talk to the on-board MSP430 Flight MCU
on the FM430 Flight Module.

There are also three views of the three accelerometers that were
attached:
http://www.cubesatkit.com/image/vibe-test_yaxis-xlr-inside.jpg,
http://www.cubesatkit.com/image/vibe-test_yaxis-xlr-outside.jpg and
http://www.cubesatkit.com/image/vibe-test_zaxis-xlr.jpg.

Obviously we're very happy see the CubeSat Kit and its basic
sheet-metal design survive the shake test without any problems.

More information on the CubeSat Kit is available at our website,
http://www.cubesatkit.com.

Finally, Adam and I would like to thank everyone at Cal Poly for the
opportunity to formally test the CubeSat Kit alongside two other
CubeSats.