#Diy electric plotter drawing robot drivers

It is by far the most good looking one built with shield-style electronics but leaving the blinking drivers visible in all their glory. Plotter number four (The fabulous one!) was built as a birthday gift to my brother. Battery level measurement seemed like a good idea, but in reality I always resorted to doing long running plots with cabled power anyway. Also the on-board led of the Arduino is hidden behind the shield hiding the convenient blinks you get when the IR-receiver is receiving, thus making you uncertain whether you pressed that calibration button or not.

#Diy electric plotter drawing robot driver

Putting stepper driver IC:s directly on the shield, skipping the drivers shipped with the steppers, meant no more blinking leds.

Battery level watchdog, allowing 'pause - change battery - resume'.

All electronics built as a shield for the Arduino.

Plotter number three (the orange one in the video below) is very similar to its predecessor, just a few changes: Once the plotter knows d and that its current location is at B you can move around and plot wherever you like in the space between and below the anchor points. The distance m is given just counting the steps on the left stepper while moving from A to B.

#Diy electric plotter drawing robot manual

I put 20 cm markers on the left and right sewing thread to avoid needing any manual measurement. First marking position A, then moving over to position B and marking that. The setup is done by navigating the plotter with the remote control. Biggest plot done yet was about 2.5 meters wide. The new setup process worked quite nicely and gave a lot more flexibility for drawing both big and small. It was one of these 'why didn't I do this from the start'-moments.

IR-receiver for being able to control it all from a remote.ДЄdding a SD-card reader and IR-receiver was a lot easier than I first anticipated.

New setup process allowing variable distance between anchor points.

Spools moved above pen for better routing of thread and less pendulum motion.

Plotter number two (the white one in the cover image) got a few improvements: The good thing about these problems was that they forced me to put some effort into implementing a reasonable acceleration and braking.

Tip of pen offset from crossing of strings - Wicked Wobbliness.

The stepper motors are not that strong - The spools were too big.

It was a good platform for better understanding the problem space though. Also being restricted to the one meter disparity setup was frustrating. Having to re-flash the Arduino when changing design was not enjoyable. By this setup the plotter knew the coordinate system when powering up and could start drawing the paths in its memory. Setup of the plotter was done by having one meter of thread rolled out on each side and fastening them one meter apart. This first plotter had a hard-coded design written in its program on the Arduino. The cheapest possible minimalistic wall plotter. After stumbling over the dirt cheap 28BYJ-48 stepper motor I knew exactly what I was going to build: It was 2014 and I had been using Arduinos and RC-servos for various camera control projects, I had access to 3D-printing and actually some spare time (!?!). Time passed and things happened in the space of hobbyist robotics. If I recall it correctly, I looked into stepper motor weights at this point realising that my idea was not going to fly. I wanted it to be self-contained, everything in one unit with just wires connecting it to the wall. This time though I started looking more at the details realising it lacked one property I had initially envisioned a wall plotter to have. Some time later I remember showing the Hektor project website to someone presenting how fantastic I thought it was. I was very pleased to see something similar to what we had been dreaming to build actually be constructed and shared with the world! I was at peace.

In 2002 my friend showed me the awesome work of JГјrg Lehni and Uli Franke - Hektor. Of course we never had time to do anything serious back then, the ecosystem for hobbyist micro controllers was not what it is today. Me and a friend that was into everything robotics and electronics was discussing building a robot for drawing on whiteboards. I don't quite remember when it started, but I think around 1999 or so.