BristleBot Ant

This is a simple robot that has been adapted from the many different Bristlebots that can be found ALL over the web. My favorite thing about building it this way with additional components is it gives you the opportunity to fully customize your robot and have it look like your favorite type of ant! Or any other type of bug!

To build this robot you will need:

• 1 x toothbrush (preferably new)
• 2/3 x Black (or your preference) pipe cleaners
• 1 x Dromida DIDE1557 motor and matching propeller (This activity can also be done with a small vibration motor)
• 2 x 3V watch batteries - one for the lights in the head and the other for the motor on the thorax
• 1 x bobby pin
• 1 x 35mm Styrofoam ball
• 2 x small LED - I used two from a dollar store laser pointer/key ring light
• Crayola (or other brand) Model Magic Foam
• Double sided foam tape
• Superglue
• Scissors
• Snips (wire cutters)

Using the snips, cut the bobby pin in half and cut six leg segments from the pipe cleaners. Start them off at about 5cm long and this will give you some leeway for trimming them later.

Secondly use the snips to cut the head of the toothbrush away from the handle, leaving 1.5 to 2cm - this is important as it will be used as the anchor for the abdomen (the back bit).

Lay the legs and bobby pin on the back of the toothbrush and superglue them in place. Leave plenty of the bobby pin (about 3cm) hanging over the edge as this will be used to anchor the head.

Take a piece of the double sided foam tape and stick it down hard on the legs and pipe cleaner as an extra way of securing them to the toothbrush, as well as providing a base to place the battery and motor. Leave the topward facing tape on for now. Leave this to set and move on to the head.

Take the Styrofoam ball and cut away a quarter chunk of the entire sphere. This hole will be the siting place for your robot's eyes. Take a small piece of the modelling foam and work it in the hole you have created, covering all the messy Styrofoam. Now take one of the batteries and place it positive (top) side down in the modelling clay. Don't leave it in there so long that it adheres (sticks) permanently to the clay, but when you remove it, there should be a battery shaped hole in the clay, ready for later.

To decorate the head, stick the remaining half of the bobby pin in the back of the head and hold onto that as you color the head in any color or design you desire. Once finished leave this to dry and go back to the thorax. You can recolor the head throughout the process and again - color it any way you choose!

The motor I used for this project, Dromida DIDE1557, is not perfect but is an adequate substitute for a vibration motor (which will give more movement).

Prepare the motor by snipping off the plug and stripping the wires back so there is about a 1/4cm of wire showing.

Clip the propeller onto the motor and then snip off one of the arms! Now experiment to see how much of the remaining blade you would like to leave/how much will fit where you are planning to mount (put/stick) it. Where you mount it will affect how your robot will move. As can be seen above I mounted mine facing forward, with the wires trailing towards the abdomen (back bit) and added two layers of the foam tape in order to raise my motor slightly.

Trim the remaining blade carefully until you are happy - and you can always test it by pressing the wires (using your fingers) to the unmounted battery. Once happy, mount the motor by peeling off the top cover from the foam tape and push the motor firmly into the tape.

Remove the foam tape top cover from where you plan to mount the thorax battery.

VERY CAREFULLY take the unmounted battery and push it on to the now uncovered and sticky foam tape ENSURING that the exposed wires from the gray wire are BETWEEN the foam tape and the positive (flat) side of the battery.

Cut a small piece of the foam tape and place the exposed wires from the black wire on the sticky side of the tape. This is your on/off switch! Now if you place this on the negative side of the now-mounted battery you will complete the circuit and see your bot move for the first time!

Unstick the on/off switch to save battery, place a small piece of the modelling clay on the back of it and go back to the head. And if your robot is very unbalanced at this time, use a small piece of modelling clay on the abdomen as a counter-weight.

Take the head battery out of its mounting place and gather your two LEDs. Each LED has two wires coming down from the bulb - one is the anode and the cathode, with the cathode being the shorter of the two. Slide the LEDs onto the battery with the anode touching the positive (flat) side and the cathode touching the negative (ridged) side. If the lights are continually on, bend the cathodes slightly up so they are not in permanent contact.

Take a small piece of foam tape and create a similar on/off switch like you created in Step 3, reconnecting the cathodes with the negative side.. Now when you are ready you can place the battery back in the slot you made in the clay.

Using four small pieces of pipe cleaner, fashion your antenna and mandibles (feelers and jaws) and push them into the Styrofoam ball.

To finish the head, take a small piece of the remaining model magic clay and fill in the rest of the hole in the sphere. Remove and throw away the bobby pin piece if you used it while coloring in the end.

Attach the head to the thorax by placing a small amount of superglue on the end of the thorax bobby pin and pushing the Styrofoam head carefully onto it - leaving plenty of space for your propeller to turn. This leaves you with a slightly wobbly ant head!

Take a small piece of the modelling clay, mould it into a thorax/oval shape and push it firmly on to the exposed toothbrush handle.

You have finished your bot!

Customize and personalize your robot by using different colored markerts/clay/LEDs. Try making a different Thorax using another Styrofoam ball or a Christmas ornament! Above all have fun and be sure to check out our upcoming events at: www.naarpl.org/makerspace