Drawing Robot With Adafruit Shield (Make It Move Contest)

Hello my names Jacob and I live in the UK. In this project I am going to build a robot that draws for you.

*I'm sure many of you want to see it so if you want to know please skip right to the second to last step but be sure to come back here to see how I made it*

I originally intended to design a mini 3d printer that could be portable and run off a 12v battery similar to this https://www.youtube.com/watch?v=vCUbUTh70UI . However, I didn't have the parts for it so I had to improvise. I designed all of the 3d printed parts in tinkercad and to fit all my parts as some dvd drives are different to others. Lets get started!

2x Old pc DVD drives that you don't mind destroying.

1x small servo. I used the SG90 servo.

1x arduino.

1x 3D printer. I've got an anet a8.

1x adafruit stepper motor driver shield. NOT ARDUINO VERSION AS IT ONLY HAS SPACE FOR ONE STEPPER MOTOR.

1x 9v battery or 12v psu.

I decided to use dvd drives as the motors because they work by having a small laser that moves around in order to write stuff on to the disk and read ( engraving information). Also, this will work on a very tight budget as they are found in everything. This process has to be done very carefully so it dosen't mess up. This is great for writing as it needs to be very particular. I didn't get any pictures of taking it apart as I wasn't sure whether I was going to post this. But all it involved was taking out the metal part inside that has the little rails and a small stepper motor beside it.

I designed these parts so it would just slot on and then I could hot glue it. Please see the information down below on how I designed these parts. There is a video up the top of me designing a servo mount then printing it.

I designed a little holder in tinkercad that slot on to the dvd drive laser mechanism and then you just hot glue . Please excuse me for my sloppy hot glueing. This is actualy my first time using a glue gun properly.

The first thing I designed was a thing that would slot on the the laser raising it up so I would have clearance for the platform. Then I designed the platform its self in tinker cad. This platform would just glue on to the Y axis raiser. I designed this with screw holes for the motor and with holes on the sides to put the rail through. The last thing I designed was a thing for the laser to slide through as this particular one didn't have two rails.

I have a colour diagram

Colour keys:

BLUE: servo

Purple/pink: Lever arm.

Orange: pencil.

Black: pencil holders one of which moves up and down.

Red: Holder arm

This is a very simple actuator used quite commonly. I got the servo and the lever arm model off of thingiverse but everything else is designed by me.

All 3d prints and glueing are done now!.

I just glued on a piece of wood and you can print and optional 40x40mm bed if you want.

For this I used an arduino uno and an adafruit shield. This should do the job as the arduino itself can control servos and the shield suports 2 stepper motors. To find out which cables to use on a motor you use a multi meter on the resistance function. This will tell you which Windings are which as when you put one cable and any other cable of the motor together if it's the right Windings it should have a resistance;IFnot, nothing will show. Wiring is simple just simply put the plus and minus for one winging in one side and the for the other. The servo is even simpler as it just involves puting a connector on the shield board. I got my Dad to help me with the soldering.

For firmware I used CNC code. For software I used Gctrl. I will capture a video once fully working. Thanks for reading!.

I still have tweaking to do but for the most part it's done!!!

Although this is, for the most part done, there could be room for improvement...

I think one thing I would do is definatley change the motors to proper stepper motors not just tiny ones without much torque. I would also change the moving system; instead of having a screw driven actuator, I'd have most axis belt driven. Last but certainly not least, I would change the diameter of the pen holders and the servo! This is important as it allows you to use any pen or pencil. THanks for reading 😃.