Simple Bots: Skitter

Step 1: Simple Bots: Skitter

Skitter Bot came into this world as result of a chain reaction of exploded of cosmic energy. By current estimates, this chain reaction took roughly 13.7 billion years to complete. When put into such context, it becomes quite clear just how long it takes for near-perfect walking scrub brush bot to come into being.

Do not be fooled. Scrub Bot was not the simple sort of bot that materializes overnight when I zip tie a bunch of scrub brushes together. No! There was an ineffable cosmic plan that led up to this bot's creation, going back well beyond the day when man, through genetic mutation, first evolved the ability to manufacture zip ties and scrub brushes. This bot is a bona fide cosmic child.

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Step 2: Go get stuff

You will need:

(x1) continuous rotation servo modified for direct drive**
(x1) 3 x AA battery holder
(x1) DPDT toggle switch
(x4) scrub brushes
(x1) small plastic container
(x1) ballpoint pen
(x1) 1-1/2" x 3/8" corner brace
(x1) assorted zip ties

**Modify your servos for direct drive here

Step 3: Drill

Drill four 1/8" holes into each corner of the servo horn.

Step 4: Attach

Pass two zip ties down through the front two holes in the servo horn.

Next, pass them through the two adjacent center-most holes in the corner bracket.

Then, pass the zip ties through the hanging holes in the brush handle.

Finally, zip tie everything firmly together.

Step 5: Drill

Use the two free holes in the L-brackets as guides for drilling downward through each of the brushes.

Step 6: Secure

Securely zip tie the brushes to the L-bracket.

For extra support, zip tie the brush handle mounting ring to the unused back holes of the servo horn.

Step 7: Cut

Center the backside of your servo near one of the short edges of the plastic container lid.

Trace the outline of the back of the servo and then cut out the shape with a razor blade.

Finally, pass the motor wires through the hole and slide the plastic container lid down over the servo.

Step 8: Drill and fasten

Drill 1/8" holes in the plastic container lid that line up with the mounting holes of the servo.

Zip tie the motor firmly in place.

Trim away the excess zip tie ends if you haven't done so already.

Step 9: Center and drill

Center the battery holder over the underside of the plastic container and use the holder's mounting holes as drill guides.

Drill two 1/8" holes.

Step 10: Attach

Place the battery holder inside the plastic container and fasten the two items together using nuts and bolts.

Step 11: Measure and drill

Take the two remaining scrubbers and measure 1" in from the edge and make a mark.

Drill a 1/8" hole down through the handle where you made this mark.

Step 12: Attach the legs

Turn the plastic container upside down. Mark, drill, and zip tie the two remaining scrub brushes to the front of the plastic container such that they meet at a 90 degree angle, and point evenly downwards towards the direction of the plastic container opening.

In other words, make two even-length front legs for your bot.

Step 13: Switch

Drill a 1/4" centered hole near the other short edge of the plastic container lid.

Pass the DPDT switch through so that the shaft is pointing at the scrubber legs and then fasten it on with a nut.

Step 14: Wire it up

Wire together the opposite corners of the DPDT switch.

Solder the red battery wire to one of the center DPDT switch pins and the black battery wire to the other.

Turn the switch so that there are only two pins facing you (as opposed to three). Solder the black motor wire to the DPDT pin closest to you on the right. Solder the red motor wire to the other pin on the left.

Note: If, when you power it up, the switch isn't making the motor move back and forth, remove the batteries. Next, detach the motor wires and reverse the switch pins they were connected to.

Step 15: Extender

Take apart a pen and cut about 1-1/2" from the end of the pen tube.

Step 16: Glue

Make certain the switch is positioned between the two scrubbers.

Fill the pen cap with hot glue and quickly slide it onto the switch's shaft. Be careful not to get any hot glue inside the switch. This could prevent it from working.

Hold the tube in place until it begins to set.

Step 17: Power

Put some batteries into the holder and the legs will start to go.

Step 18: Case closed

Quickly close the plastic container and let the bot go free.