Simple Bots: Barreller




About: My name is Randy and I am a Community Manager in these here parts. In a previous life I had founded and run the Instructables Design Studio (RIP) @ Autodesk's Pier 9 Technology Center. I'm also the author ...

A Barreller Bot is a device that has seemingly eternal forward propulsion in a given direction. In other words, there is a motor that acts as an off-centered weight inside of a can. When the can rolls forward in the direction of the weight (the weight, being the motor), the motor turns upwards, hence, causing the can to roll forward again. Now, imagine this happening really quickly and for a sustained amount of time. It would give the can the appearance of rolling forward on its own and even cause it to do seemingly impossible things, like rolling up inclines. This bot is great fun! If you don't believe me, build one for yourself. It is quick and easy to do.

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Step 1: Go Get Stuff

You will need:

(x1) continuous rotation servo modified for direct drive **
(x1) paint can (or similar)
(x2) 1" paintbrushes
(x1) 4 x AA battery holder
(x4) AA batteries
(x1) tilt switch (Mouser #107-2002-EV)
(x1) assorted zip ties
(x1) template (see below)

**Learn to remove a servo controller board at this page.

Step 2: Disassemble the Brush

Take apart the paint brush such that you are left with the two wooden handles.

Step 3: Zip Tie

Put batteries into the battery holder and lay it down on top of a zip tie with the batteries facing down.

Place the motor on top such that the servo horn (the gear-looking object) sticks off perpendicularly in one direction and the wooden handles are sticking off in the opposite direction.

Zip tie it all together until it is one singular unit and won't fall apart.

Step 4: Wire It Up

Twist together the black wire from the motor with the black wire from the battery holder and solder the connection.

Solder the red wire from the battery holder to the little spike that sticks out of the tilt switch. Solder the red wire from the motor to the round metallic body of the tilt switch.

It makes it easier to solder to the tilt switch if you place a small pool of solder on it first.

Step 5: Clean the Can

Remove from the can anything that will prevent it from rolling, such as handles, and clean out anything that may already be inside.

Step 6: Drill Holes

If you have not done so already, print and cut out the template.

Tape the template to the bottom of the can and drill the four smaller holes with an 1/8" drill bit or one appropriately sized for your zip ties.

Step 7: Put It Together

Slip the zip tie between two of the batteries in the battery holder such that it is parallel with them. However, make certain this doesn't short out the switch. If you are concerned, wrap the switch once around with electrical tape.

Zip tie the servo horn to the holes that you drill in the bottom of the can. You may need to drill and/or widen the holes in the servo horn to accommodate the zip tie that you are using.

Trim the excess piece of zip tie when you are done.

Step 8: Case Closed

Put the lid back on when you are done.

If you store the can upright (in its normal position) it will keep the device from turning on.

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    53 Discussions


    1 year ago

    AWESOME! I made one with my own design (inspired by you) and it is great. thanks for the idea.

    1 reply

    Reply 1 year ago

    Glad it worked out for you. If you can, you should share a picture so others can see what you made :)


    if u were to make two of them, half the width they are now, and have seperate control board, attach the two together so they can move freely, would it turn, if u get 2 board with the same frequency, it may be possible to use the same remote for forward, reverse, and steering if i had the time i would try it, but sadly i dont


    8 years ago on Step 3

    wooohhh astig..


    9 years ago on Introduction

    I made something like this but with rubberband power. on one end the rubber band glued or something and the other end is connected to a stick on the outside of the can. as the rubberband would unwind it would push the stick against the ground and push it forward. i might just make an 'ible for it now. Anyway, somewhat different ideas but excellent work


    9 years ago on Introduction

    Did anyone try my idea? i tried it, but i found more success by using a belt instead of a gear, but u have to make the weight a little heavier

    2 replies

    Reply 9 years ago on Introduction

    I gave the one i made to a friend because i wasnt happy with the way it came out, it worked fine, but i did a diy with the barrel, and it was coming apart, im going to make a new one and ill take pictures, once i find some plastic xD, i got a heatgun so ill probably melt the plastic together instead of pvc glue


    9 years ago on Step 2

    hay just found you and your amazing simple bots, and i have one suggestion. you could use those brushes for a-mazing bristle bot


    Reply 9 years ago on Introduction

    Please, what are the paint brush handles for? Could they be replaced by something else, and in that case what would the requirements be then?


    Reply 9 years ago on Introduction

    They are there mainly to add a little extra weight across the can. Also, they help with zip tying the battery pack to the motor in an off-centered fashion (as it creates a larger surface area than the motor body). Replace them with anything you like.


    9 years ago on Introduction

    if you make sure the container is sealed, you could use it in water, it may float, and if it floats, it may be able to move around, and if you make it HUGE enough it may be able to go up things, QUICK SOMONE FIND A HUGE CONTAINER AND USE MY DIAGRAM, REPLACE THE ELECTRIC MOTOR WITH A WEED WHACKER ENGINE AND WEIGH IT DOWN WITH A CHAIR then follow these steps step one : get in step 2 : seal it up step 3, sit down step 4 : start engine step 5: pull throttle step 6: go down the street with it xD see peoples reactions step 7: try driveing it into a lake and see if it floats step 8: if you made it big enough, try going over things