As the ADCS Hardware Engineer for the Dalhousie Space Systems Lab, I am tasked with all preliminary tests necessary to confirm the functionality of our ADCS equipment. For the MANTIS project, we selected CubeSpace from South Africa to supply our COTS ADCS system.

Upon receipt of our equipment, it is necessary to perform a health acceptance check to ensure nothing was damaged in shipping. Instructions for performing this health check are included in Chapter 6 of the CubeSpace User Manual (version 1.07 was used for this test).

Required Equipment

• Switching power supply unit (this test uses 12 V, 1.50 A)
• Multimeter
• Grounded work station
• Personal ESD equipment
• Gloves
• Computer with CubeSupport software installed

Supplied Equipment

The ADCS system we ordered for the MANTIS satellite is composed of the following components:

• CubeADCS Core Stack
  • Contains motherboard (CubeComputer)
  • Contains three orthogonal reaction wheels (CW0057)
  • Contains three magnetorquers
• CubeSense Sun Sensors (x4)
• CubeSense Coarse Sun Sensors (x10)
• CubeMag CompactMag
• CubeMag MagDeploy
• CubeSupport Board
• USB-Serial FTDI cable
• DC power barrel jack connector
• PC104 adapter

Equipment comes in a protective case. Each component is packaged in an ESD-safe with an extreme amount of Kapton tape. Each component must be carefully unwrapped, which can take up to an hour.

First Impressions

With everything out of the packaging, we are ready to fire up the system. Using the CubeSupport PCB, the DC barrel jack connector, the PC104 adapter, wiring harness, and the CubeADCS Core stack, we can begin the health check acceptance test.

With power connected, there is a boot sequence described in the user manual that must be followed in order to access the CubeComputer bootloader. Using the CubeSupport software, we can access telemetry over the serial FTDI connector.

Health Acceptance Check Requirements

The health acceptance check document is roughly 40 pages, and closely defines the requirements that each shipped component must meet in order to be deemed fit for launch. Using the CubeSupport software, we can change settings of peripherals, control the actuators, and get live measurements of voltages and currents inside the core stack. Every measurement taken must be entered into the health check document and compared to acceptable values.

One condensed example for the health check is as follows:

1. Set the speed of reaction wheel 1 to 500 rpm.
2. Read the speed of reaction wheel 1 using the internal tachometer and verify that it is accurate to within 1% of the setpoint.
3. Read the live current measurements for the reaction wheels and verify that the current draw of reaction wheel 1 is roughly 3 mA.
4. With the wheel off, measure the baseline current draw of the motor controller and compare to acceptable values.
5. Then repeat these steps for the other two reaction wheels at varying speeds.

The fully assembled testbench is shown in the photo below.

The attached peripherals shown in this photo are the CubeSense Sun Sensors (4x), the CubeMag CompactMag, and the MagDeploy. All telemetry data is processed through the CubeComputer and sent to the CubeSupport software over serial.

Once the health check acceptance document was completed, our team signed-off and sent the document back to CubeSpace for their verification and acknowledgement.

For updates and further information on the MANTIS project, visit the Dalhousie Space Systems Lab website: https://dsslabs.ca/