Week 19

This week I was busy traveling and did not make a lot of progress on the final project.

Cover

I finished printing the dual-color print for the cover with the logo for the machine and fitted it. I'm quite happy with the result.

GPS fix issues

I wanted to see the machine in action and record a full 24h circle of it in operation. I therefore set it up in the back garden and waited for the GPS fix, but nothing happened. Even after more then one hour I didn't get a GPS fix. First I thought it might be due to the restricted visibility as the place was surrounded by buildings, but even from another place I couldn't get a GPS fix.

I connected my laptop and printed the messages from the GPS module to see what is going on. It turned out, that for some reason the GPS module seems to reboot constantly, so this was obviously preventing it from getting the fix and needs further investigation.

I suspected some electrical issue and measured the current used by the GPS module. It measured around 70 mA and seemed to drop down, when it was restarting. I realized, that together with the two encoders, the LED and the microcontroller, I might have reached the current limit of the voltage regulator. Therefore I unsoldered the tiny 100 mA voltage regulator from the PCB and wired a new one I had in my inventory to it. Here is a link to it.