QUAIL is completed! Well, it took WAY longer than expected. Life got very busy for me over the last few months, and I struggled to find the time and motivation to get this thing over the line. The last requirement for the project was to ‘close the loop’, and figure out a nice way to feedback the state of the sensor bar. Thankfully, it was all pretty simple once I got going again.
Failure to encode Tragically, we have hit a speed-bump with the project, the phototransistor on one of the encoders is dead. Obviously this calls for a moment of silence. The rest of the circuit appears to be working fine, however. While I did want to implement the code to utilise the encoders, it was never actually needed in order to get the robot to follow a line. I could probably replace the part and get it working again, but I do not feel it is worth the effort given the scope of the project.
I wanted to write this to act as a quick lookup for anyone who needs it (Mostly me). Almost all of the guides I found mention inserting a launch-prefix into a launch file to launch gdb with the node, but I don’t like doing that. I don’t want to have start gdb from scratch and manually insert the break-points each time I want to debug. That’s goofy. Also, I’d like to use my editor’s built-in debugging tools.
The Motor Driver Node Getting an output from the PI If we’re going to drive the motors, we’re going to need some method of interfacing with the GPIO output pins on the Pi. After doing some reading and researching, I think that pigpio (Probably pronounced pi-gpio, and not pig-pio like my mind keeps reading it as) perfectly fits the bill for what we are looking for. There is a small potential caveat about using pigpio, which is that under normal operation, it requires sudo access.