Thought I would give another update. Solar test #6 is going ok, not great, just ok. Had rained last night, so I bought the test unit in for the night. The test unit is not at all weather tight.
I think I have a bad battery or charger, as the middle charger never shows its blue light. I replaced the battery and will see how the test goes. Adding the camera helps with monitoring the chargers.
I am finding, though, that a hard-off is not good for the OS. I knew that but never really cared until now. Also, the LIPO SHIM is not restarting the Pi after a brownout. I am looking into a solution with a 3.3-volt Arduino M0 to send a shutdown to the PI and use a 3v relay or MOSFET. I will set the relay so that when the voltage is applied, the PI’s power is interrupted. The Arduino would shut down the Pi nightly and turn it on again during the day.
Challenges to things about:
- Shutting down the Pi nicely, I am thinking of using the existing LIPO shim and the M0 to toggle the GPO on the Pi. I am going to go with the relay solution first.
- Timing. The Andrino doesn’t have a Real Time Clock. I will get some time drift over time as the Arduino is just waiting for a period of time and not using a clock. May need the Pi to restart the Arduino. More thinking on this one.
- I am also looking at a solution for using Arduino to monitor power input and output. Power input to make sure it’s ok to turn on the Pi. Power Output to see if a motor gets overloaded while driving.
- I wonder if four batteries, four charges, and three solar panels would work better. That may be Solar Test 7. I am getting blue lights on the chargers mid-morning, so I might have enough solar power to charge four batteries.
- I ordered an XYZ Divinci Pro 3D Printer to start printing in PETG. PLA is going to get soft during the daytime heat and when the rover is driving. I don’t need the rover to fail because of the PLA. The reviews for that printer are not the best on Amazon, but I have a trusted friend that has one, and he is happy with it. I will make sure I let everyone know my thoughts on this printer. Once I get the printer, I will start the design process again. I have new motors to use, so there will be some redesign.
- Remote Update of the Arduino and Pi.
- Data plan, how much will I need? If I process the photos on the Pi, I don’t think I will need much. I won’t know until I get further along in the project. I will be lucky to get it out there by the end of summer.