Phase D Build and Test Plan
Spacecraft Level Test and Shipment
The spacecraft level test consists of the final collection of verification activities to demonstrate Iris's compliance with subsystem and mission requirements. Individual verification activities are created by their respective subsystem leads, and reviewed by the team to identify the best place to undertake each activity. Verification activities are either inspection or test. Inspections can occur at any time throughout the AIT process to confirm measurements (such as mass and dimensions) or demonstrate that a feature is in place. Functional tests are verification activities that demonstrate that the satellite operates as intended or that a software feature is in place. Functional tests occurs before and after each factor that can create stress on the satellite, enabling the team to provide a functioning CubeSat to the Canadian CubeSat Project. Figure 1 shows current system level test outline.
The Iris team begins the functional test activity after CubeSat integration (Highlighted as the orange start block in Figure 1). A summary of each step is outlined below:
Fit Check - The step after CubeSat integration is a fit check, demonstrating that Iris is able to fit inside the NRCSD and meets all size requirements.
Mass Inspection - Iris will be placed on a scale to confirm total mass is less than 4.8 kg.
Over Air RF Com Test - The Iris team will communicate with Iris using the University of Manitoba ground station.
Vibration Test - A vibration table will be used to subject the CubeSat to the vibration requirements as required by NanoRacks [1]. The CubeSat will be installed on the vibration table to subject along the X, Y, and Z axis at +6dB for 120 seconds. At the end of all vibration orientations, a functional test will be undertaken to demonstrate Iris's ability to survive the launch environment. After the completion of the vibration test, a reduced functional test will be undertaken to demonstrate Iris vibration resilience.
Final Packaging - After a final functional test, the project team packages Iris to Nanoracks.
Shipment - Iris is shipped to Nanoracks. If possible, one final functional test is undertaken at the launch site.
In addition, the power test plan is linked below.
Functional tests occur after every step of the system level test and shipment process, and are used to demonstrate CubeSat functionality during or after environments that cause stress on the system. Functional tests are planned throughout the process based on expected accessibility and available tools. There are three planned planned versions of the functional test outlined below:
Full System Level Functional Test (F) - A collection of verification activities that will demonstrate compliance to the concept of operations, interface functionality, software functionality, and working deployables.
Reduced System Level Functional Test (F*) - Due to no physical access into the TVAC chamber, the Iris team will not be able to test and reset the deployables between steps 6 through 9. However, all other functional test activities will be undertaken to demonstrate a working satellite during each thermal plateau vacuum environments.
The reduced functional test is made up of the verification activities below.
In addition to the activities in the Reduced System Level Functional Test (F*), the deployable tests conducted during the Full System Level Functional Tests are outlined below. Two deployables will be tested: the antenna located in the COMMS module and the solar panel arrays located on the outside of the spacecraft.
1. Solar Panel Deployment Test
Procedure
Program the CDH to command the PWR subsystem to supply power to the burn wire resistor attached to the burn wire holding the solar panel arrays to the main structure. Record the time it takes to heat the resistor and melt the burn wire. Verify that the burn wire melts and the solar panel array deploy with a pass criteria that the solar panels deploy parallel to the front of the satellite +- 10 degrees.
Inspect the solar panel wings to ensure the springs keep contact and solidly hold the hinges in their deployed positions.
Once the solar panels are deployed, detach the burn wire from the main structure and the solar panel arrays and replace it with a new burn wire. This should be accessible from the outside of the spacecraft at the highlighted location in Figure 2.
Tie-down the solar panel wings to the main structure using the new burn wire. Inspect to verify that the solar panel wings are secured to the main structure.
Figure 2: Solar Panel Burn Wire
2. Comms Antenna Deployment Test
Procedure:
Program the CDH to command the PWR subsystem to supply power to the burn wire resistor attached to the burn wire holding the antenna in the COMMS subsystem. Record the time it takes to heat the resistor and melt the burn wire. Verify that the burn wire melts and that the antenna fully deploys out of the COMMS module.
Inspect the antenna hinge to ensure the springs keep contact and solidly hold the hinges in their deployed positions.
Once the antenna is deployed and hinges are inspected, detach the burn wire from the main structure (located inside the COMMS module) replace it with a new burn wire. This should be accessible via the opening on the COMMS module as highlighted in Figure 3.
Roll the antenna back into the COMMS antenna assembly module and secure the antenna module into the COMMS structural module using the new burn wire. Inspect to verify that the antenna module is secured to the main structure.
Figure 3: COMMS Antenna Burn Wire
[1] NanoRacks CubeSat Deployer Interface Definition Document - Requirement 4.3.2.1