CubeSat Standards

The CubeSat is a type of miniature satellite designed with a volume of exactly 10cm³ and a weight of up to 1.33 kilograms. The satellite was developed by both Stanford and California Polytechnic Universities with the purpose of helping other universities preform space science and exploration.

The following is a summary of the Design Specifications for a CubeSat created by CalPoly University.

General Responsibilities

  • CubeSats must not present any danger to neighboring CubeSats in the P-POD, the LV, or primary payloads.
  • All parts must remain attached to the CubeSats during launch, ejection and operation. No additional space debris may be created.
  • CubeSats must be designed to minimize jamming in the P-POD.
  • Absolutely no pyrotechnics are allowed inside the CubeSat.
  • NASA approved materials should be used whenever possible to prevent contamination of other spacecraft during integration, testing, and launch.
  • The newest revision of the CubeSat Specification is always the official version.
  • Developers are responsible for being aware of changes.
  • Changes will be made as infrequently as possible bearing launch provider requirements or widespread safety concerns within the community.
  • Cal Poly will send an update to the CubeSat mailing list upon any changes tothe specification.
  • CubeSats using an older version of the specification may be exempt from implementing changes to the specification on a case-by-case basis. Cal Poly holds final approval of all CubeSat designs. Any deviations from the specification must be approved by Cal Poly launch personnel. Any CubeSat deemed asafety hazard by Cal Poly launch personnel may be pulled from the launch.

Dimensional and Mass Requirements

  • CubeSats are cube shaped picosatellites with a nominal length of 100 mm per side. Dimensions and features are outlined in the CubeSat Specification Drawing.
  • General features of all CubeSats are:
  • Each single CubeSat may not exceed 1 kg mass.
  • Center of mass must be within 2 cm of its geometric center.
  • Double and triple configurations are possible. In this case allowable mass 2 kg or 3 kg respectively. Only the dimensions in the Z axis change (227 mm for doubles and 340.5 mm for triples). X and Y dimensions remain the same.

Structural Requirements

  • The structure of the CubeSat must be strong enough to survive maximum loading defined in the testing requirements and cumulative loading of all required tests and launch.
  • The CubeSat structure must be compatible with the P-POD.
  • Rails must be smooth and edges must be rounded to a minimum radius of 1 mm.
  • At least 75% (85.125 mm of a possible 113.5mm) of the rail must be in contact with the P-POD rails. 25% of the rails may be recessed and NO part of the rails may exceed the specification.
  • All rails must be hard anodized to prevent cold-welding, reduce wear, and provide electrical isolation between the CubeSats and the P-POD.
  • Separation springs must be included at designated contact points (Attachment 1). Spring plungers are recommended (McMaster-Carr P/N: 84985A76 available at A custom separation system may be used, but must be approved by Cal Poly launch personnel.
  • The use of Aluminum 7075 or 6061-T6 is suggested for the main structure. If other materials are used, the thermal expansion must be similar to that of Aluminum 7075-T73 (P-POD material) and approved by Cal Poly launch personnel.
  • Deployables must be constrained by the CubeSat. The P-POD rails and walls are NOT to be used to constrain delpolyables.

Electrical Requirements

  • Electronic systems must be designed with the following safety features.
  • No electronics may be active during launch to prevent any electrical or RF interference with the launch vehicle and primary payloads. CubeSats with rechargeable batteries must be fully deactivated during launch or launch withdischarged batteries.
  • One deployment switch is required (two are recommended) for each CubeSat. The deployment switch should be located at designated points.
  • Developers who wish to perform testing and battery charging after integration must provide ground support equipment (GSE) that connects to the CubeSat through designated data ports.
  • A remove before flight (RBF) pin is required to deactivate the CubeSats during integration outside the P-POD. The pin will be removed once the CubeSats are placed inside the P-POD. RBF pins must fit within the designated data ports. RBF pins should not protrude more than 6.5 mm from the rails when fully inserted.

Operational Requirements

CubeSats must meet certain requirements pertaining to integration and operation to meet legal obligations and ensure safety of other CubeSats.

  • CubeSats with rechargeable batteries must have the capability to receive a transmitter shutdown command, as per FCC regulation.
  • To allow adequate separation of CubeSats, antennas may be deployed 15 minutes after ejection from the P-POD (as detected by CubeSat deployment switches). Larger deployables such as booms and solar panels may be deployed 30 minutes after ejection from the P-POD.
  • CubeSats may enter low power transmit mode (LPTM) 15 minutes after ejection from the P-POD. LPTM is defined as short, periodic beacons from the CubeSat. CubeSats may activate all primary transmitters, or enter high power transmitmode (HPTM) 30 minutes after ejection from the P-POD.
  • Operators must obtain and provide documentation of proper licenses for use of frequencies. For amateur frequency use, this requires proof of frequency coordination by the International Amateur Radio Union (IARU). Applications can be found at
  • Developers must obtain and provide documentation of approval of an orbital debris mitigation plan from the Federal Communications Commission (FCC). Contact Robert Nelson at gro.ccf|noslenr#gro.ccf|noslenr
  • Cal Poly will conduct a minimum of one fit check in which developer hardware will be inspected and integrated into the P-POD. A final fit check will be conducted prior to launch. The CubeSat Acceptance Checklist (CAC) will beused to verify compliance of the specification. Additionally, periodic teleconferences, videoconferences, and progress reports may be required.

Testing Requirements

  • Testing must be performed to meet all launch provider requirements as well as any additional testing requirements deemed necessary to ensure the safety of the CubeSats and the P-POD. All flight hardware will undergo qualification and acceptance testing. The P-PODs will be tested in a similar fashion to ensure the safety and workmanship before integration with CubeSats. At the very minimum, all CubeSats will undergo the following tests.
  • Random vibration testing at a level higher than the published launch vehicle envelope outlined in the MTP.
  • Thermal vacuum bakeout to ensure proper outgassing of components. The test cycle and duration will be outlined in the MTP.
  • Visual inspection of the CubeSat and measurement of critical areas as per the CubeSat Acceptance Checklist (CAC).