I finally ran into an issue that I have been dreading for a while: Encoding the actual position of the LIDAR pulley mechanism. Now that the LIDAR scan works, I need accurate position data alongside the measurements. As reliable as my ridiculously powerful stepper is, it’s not a servo and doesn’t know which position it starts from. There are various ways of solving this, with varying levels of budget and difficulty: ...
After a few days of struggling with stepper motor controls, I finally got everything working reliably last night. There were a lot of learnings along the way, most of them not very well explained on most tutorials I found online. My problem was essentially that I have a ridiculously powerful set of steppers. I kept referring to them as NEMA-14, but while reading this guide from Adafruit, I learned that NEMA nomenclature doesn’t mean much other than enclosure size. ...
I got the stepper motor working tonight. This was significantly harder than I expected. I had several motor driver boards lying around, and thought I would make my job easier and use an Arduino Motor Shield. As it turns out, running steppers with it is not that straightforward. I tried several libraries, everything from the standard Stepper library to the AccelStepper, which is supposed to be state of the art. There are a few things that threw me off, in no particular order: ...
I have been researching various ways to build a radar for robotic projects. I already have a Garmin LIDAR Lite I had bought years ago, so LIDAR seems to be the best way to go. However, my research shows that there are several additional parts that are also required: A slip ring, to keep the rotating LIDAR module in connection with the rest of the robot Some kind of pulley mechanism to rotate the unit A stepper motor or a brushed motor for rotation In the case of a brushed motor, an encoder would be needed to calculate exact position Wide metal bearing of some sort A timing belt or similar for pulley I found several projects that show some level of success with this method: ...
ZoomBox is ready! I designed and printed the top part and fitted the arcade buttons in. I wanted the button icons to be extruded out, which presented a problem. If I extruded them, I couldn’t print the top part upside down. Eventually I decided to print without them and then printed them separately in black filament. Then used a white acrylic pencil to contour the icons. I am pretty happy with the result. ...