Impediments to Proper Satellite Ejection  The ability to ensure full compression of the roller separation springs inside the Pedestals was difficult.  Since they were on the inside of the Pedestals they were hard to inspect when the ICU was fully  assembled. Fine tuning of the spring’s compression was performed with the Pedestals simply pushed  against the satellites on a table. Additional compression due to o-ring preload had to be analytically accounted for. It is unacceptable to bottom out the springs and risk damage to their Delrin guide  components so some tolerance had to be added to prevent this. This tolerance, along with the possible  variations in o-ring compression due to satellite preload is a significant percentage of the overall spring  travel. This means the exact force and energy imparted by these springs in flight was unknown and likely  lower than desired. This may have additionally contributed to the satellite ejection anomaly. Moving the springs outside the pedestals and more accurately predicting the o-ring compression would improve the  accuracy of this spring compression.   The spin-up snubber used to impart rotation on MAA may have contributed to MAA not ejecting. During  all 2D testing the snubber pe rformed flawlessly. Post flight dynamic analysis of the separation event  revealed that as MAA ejects its countersink rides up on the snubber, temporarily pushing the satellite  against the opposite side of the cylinder. During normal ejection this is fine. As the Avionics Deck quickly separates from the MAA Cylinder, the roller separation springs are long e nough to overcome the  temporary rubbing of the satellite against the cylinder. Howeve r, the combination of the Avionics Deck not  immediately releasing and the po ssible shortened spring travel may have combined to stop MAA on the  snubber.    The implementation of the conical snubbers used as satellite inhibits and to prevent rotation  unnecessarily complicated the integration process and separation event. The snubbers could not be seen  during installation of the satellites onto the Avionics Deck. Thus, alignment marks were devised to ensure  the snubbers were concentric to their accepting countersinks. However, even with these marks it was  difficult to confirm the exact position of the snubbers. If not perfectly aligned they may have gouged the  surface of the satellite as the o-ring was compressed during preloading. They also may have prevented  MAA from properly rotating out of the cylinder during ejection. Since they are located on the Avionics Deck, as the sphere attempts to rotate out of the cylinde r, the snubbers may have been in the way,  temporarily jamming the satellite. Ideally these snubbers would be removed. Testing should be performed  to verify that the sphere will not move during random vibration. It is expected that a sphere with its center  of mass in the geometric center and proper preload during launch will not rotate during vibration.     Conclusion  Overall, the ICU was a great success and served its purpose as a risk reduction mission to test the  separation system of spherical satellites for future missions. It proved its functionality as a low cost means  of placing two spherical satellites into orbit. The ICU ejected smoothly from CAPE by means of the NEA  Lightband and Roller Guides. The containment and ejection system for the spheres proved feasible. The main issue was the oversight of assuming a perfectly simultaneous separation. This however can be  corrected by purposely staggering the ISS separations by several seconds. The inclusion of penetrating  snubbers on the satellites complicated the separation event. Other means of imparting rotation to the  satellite should be considered, including self spin-up after ejection. With the improved simulation software  now at the disposal of the designers, the separation event can be accurately modeled to minimize the risk of re-contact and ensure proper satellite ejection. It will also enable the de signer to account for many  different scenarios.    155