Sound-Activated Walking Robot

by littleBits

Published on April 23, 2014

This little guy has 2 mounting boards for a body. Just add littleBits and some sturdy legs to get him walking. Control his stride by adjusting the pulse and slide dimmers that connect to his servo-activated legs. Activate the sound and motion triggers and he will happily come over and greet you.

Check out the Mounting Board Tips & Tricks page here.

How To Make It


Build the circuit: power +wire + motion trigger + sound trigger + wire + bright led + pulse + wire + folk, + slide dimmer + servo (on one branch of the fork), inverter + slide dimmer + servo (on other branch of the fork). Both servos should be set to turn mode. Mask off the motion trigger with tape to desensitize it a bit. See the motion trigger tips & tricks for ideas about how to do this (http://littlebits.cc/fridays-tips-tricks-the-motion-trigger).


Sandwich two mounting boards together. The sides that connect to littleBits should be facing outwards. We placed some gluedots between two to hold them together.


Use our template to laser cut front and rear legs of the dog robot. You can use your own design of course though. Bend the rear leg (if you cut it out of acrylic you may need some tool like heat gun). Then attach the servo arms to the legs using gluedots and bind them with some thin wires.


Make four feet out of erasers or some rubbery material. Put them on the dog’s four bare feet.


Place the servos in the 3d-printed servo holders (files can be found on Thingiverse: http://www.thingiverse.com/thing:243545, http://www.thingiverse.com/thing:243546 and Shapeways: https://www.shapeways.com/model/1691988/littlebits-servo-holder-horizontal.html?li=my-models&materialId=6 https://www.shapeways.com/model/1691995/littlebits-servo-holder-vertical.html?li=search-results&materialId=90 ). Attach the servo holders at each end of the mounting board on the bottom side. Make sure that the turning axis of the servo is aligned with the centerline of the mounting board. Because the turning axis is not at the center of the servo motor, the servo holders should be a step off from the center. Before you connect the legs to the servos with small screws, you will want to test and find the best orientation for walking.


Place the motion and sound triggers in 3d-printed vertical module holders (files can be found at Thingiverse: http://www.thingiverse.com/thing:243540 and at Shapeways:https://www.shapeways.com/model/1691977/littlebits-bits-vertical-mount.html?li=aeTabs ). Position them at the front of the upper mounting board. Then slide a battery in to the 3d-printed battery holder (file can be found at Thingiverse: http://www.thingiverse.com/thing:243530 and at Shapeways:https://www.shapeways.com/model/1691959/littlebits-battery-holder.html?li=aeTabs ) and place it on his tummy.


Snap the rest of the circuit onto the mounting boards and test walking. Adjust the speed of the pulse to decide how fast he walks. Set the slide dimmers to control how far he stretches out his legs for each step. Make sure that the legs move evenly and secure them to the servos with small screws.


Make him a coat and use M3 screws to attach it through the screw holes on each corner of mounting board. You can use our coat or your design. We found that the design of the ears and tail are very important for optimal cuteness.


Everything is ready. Shout out his name, wave your hands and he will come walking to greet you.

Related Projects

littleBits Caterpillar, S. Bakal - Science Teacher

Encompassing science and literacy, this very cute and hungry caterpillar can be an extension to your Lifecycle of the Butterfly le...

#BITWARS! Yoda lifts the X-wing!

For my #Bitwars project I used the Gizmos & Gadgets kit to recreate the scene Yoda lifts the X-wing from The Empire Strikes Ba...

The Next

Track made with littleBits and OP-1