Step 6c: Solar Board Testing

For this test, you will need a fully built Solar Board and the Pi Zero with the CubeSatSim software installed. If your Pi Zero is in use, there might be an extra one for you to test with. If your Pi Zero hasn't been programmed yet, follow these instructions first V2 Pi Zero Software.

Here are the parts you need:

• Fully built Solar Board
• Raspberry Pi Zero WH with SD card with CubeSatSim software installed
• Micro USB Cable for powering Pi Zero
• A Solar Panel with connector
• LED lamp

Plug the Pi Zero into the bottom of the Solar Board and plug in the micro USB cable to power it:

When you power the Pi Zero up, the green LED on the Pi Zero should flash.

Testing Solar Board

You will need to login to your Pi Zero using SSH by following these directions: https://github.com/alanbjohnston/CubeSatSim/wiki/V2-Pi-Zero-Software#logging-into-your-raspberry-pi

When you are logged into your Pi Zero, type the command CubeSatSim/config -v then return and look for this output showing the sensors.

CubeSatSim v1.3.2 configuration tool

Real-time output from the INA219 voltage and current sensors:

CubeSatSim v1.3 INA219 Voltage and Current Telemetry

+X  |  0.91 V     0 mA 
+Y  |  0.93 V     0 mA 
+Z  |  0.93 V     0 mA 
-X  |  0.94 V     0 mA 
-Y  |  0.93 V     0 mA 
-Z  |  0.92 V     0 mA 
Bat |  0.00 V     0 mA 
Bus |  0.00 V     0 mA 

The voltages for +X, +Y, +Z, -X, -Y, and -Z will typically be less than 1V - these voltages are actually zero, but since they are unconnected ("floating"), they have this reading.

The voltages of 0.00 for Bat (Battery) and Bus are correct since there is no sensor for them.

If any other one reads 0.00 it means there is a problem with your Solar Board or if you see an error message about the I2C bus.

You can then plug a Solar Panel into the +X connector on the Solar Board and type CubeSatSim/config -v then return again (or type the up arrow to get the previous command, then return) to see the voltages again.

CubeSatSim v1.3.2 configuration tool

Real-time output from the INA219 voltage and current sensors:

CubeSatSim v1.3 INA219 Voltage and Current Telemetry

+X  |  1.48 V     0 mA 
+Y  |  0.93 V     0 mA 
+Z  |  0.93 V     0 mA 
-X  |  0.94 V     0 mA 
-Y  |  0.93 V     0 mA 
-Z  |  0.92 V     0 mA 
Bat |  0.00 V     0 mA 
Bus |  0.00 V     0 mA 

For the voltage of the +X solar panel, you should get something between 1V and 2V in normal room illumination.

Take a JST connector wire like the ones on the solar panels and solder the red and black wires together to make a short circuit wire. Illuminate the Solar Panel with a LED lamp and you will see something like this when you type CubeSatSim/config -v:

CubeSatSim v1.3.2 configuration tool

Real-time output from the INA219 voltage and current sensors:

CubeSatSim v1.3 INA219 Voltage and Current Telemetry

+X  |  6.02 V     0 mA 
+Y  |  0.93 V     0 mA 
+Z  |  0.93 V     0 mA 
-X  |  0.94 V     0 mA 
-Y  |  0.93 V     0 mA 
-Z  |  0.92 V     0 mA 
Bat |  0.00 V     0 mA 
Bus |  0.00 V     0 mA 

The +X solar panel under open circuit conditions and illuminated should give a voltage greater than 5 V.

Now plug the JST short circuit wire into the STEM or Battery JST connector:

Type a CubeSatSim/config -v then return and look for this output showing the sensors.

CubeSatSim v1.3.2 configuration tool

Real-time output from the INA219 voltage and current sensors:

CubeSatSim v1.3 INA219 Voltage and Current Telemetry

+X  |  0.02 V     3 mA 
+Y  |  0.93 V     0 mA 
+Z  |  0.93 V     0 mA 
-X  |  0.94 V     0 mA 
-Y  |  0.93 V     0 mA 
-Z  |  0.92 V     0 mA 
Bat |  0.00 V     0 mA 
Bus |  0.00 V     0 mA 

You should see a current of a few mA for +X and a voltage close to zero due to the short circuit. If you have a halogen lamp or sunlight, you can do this again and you will see a larger current of tens of mA.

Move the Solar Panel into each of the +Y, +Z, -X, -Y, and -Z connectors on the Solar Board and verify you see a few mA each time. This tests out the circuit including the diodes.

When you are finished type sudo shutdown now and after 30 seconds you can power off and unplug the Pi Zero.

The Solar Board has now been tested and is ready for the Flat Sat Testing!