Arduino Smartphone Controlled Strandbeest
Walkers. I wanted to build a walker for a long time now, and it’s finally done.
So yeah, it walks. But that’s not all there is to it, it also walks to the direction I tell it to!
This model is controlled via an Android app I developed using MIT’s app inventor tool, which “talks” to an Arduino Pro Mini through an HC-05 bluetooth module. I hacked four 9g mini servo motors to make them turn continuously (not only 180 degrees like they usually do), and placed two on each side to propel the model. The build process was surprisingly mechanically challenging.
The Strandbeest was not my first choice when I decided to build a walker, I began with this… thing:
Though I quickly decided to leave that design and began this:
The electronics for this project are fairly straightforward. The Arduino sends commands to an l293 dual H-Bridge motor controller, which switches the motor’s current drawn from a 5V regulator on or off; I decided not to use analog control for the motors because they did not seem to be as powerful/fast as I like even at max power.
I managed to make a mess even while building this simple circuit – making one motor controller explode during tests! I have probabaly shorted it and made it overheat internally, which caused it to go BOOM.
After that incident I discarded my custom shield and turned to use the safer, bought, option of the same controller with the Ardino Uno:
Haircut time! By replacing the Uno with a Pro Mini the robot got rid of most of its wires:
This model is mostly 3D printed and powered by a 5000mAh lipo battery.