A Mechanical Edge-Avoiding Robot

In the age of cheap sensors and microcontrollers, it’s easy to forget that there might be very simple mechanical solutions to a problem. [gzumwalt]’s 3D printed mechanical edge avoiding robot is a beautifully  elegant example of this.

The only electric components on this robot is a small geared DC motor and a LiPo battery. The motor drives a shaft fixed to a wheel on one side, while the opposite wheel is free-spinning. A third wheel is mounted perpendicular to the other two in the center of the robot, and is driven from the shaft by a bevel gear. The third wheel is lifted off the surface by a pair of conical wheels on a pivoting axle. When one of these conical wheels go over the edge of whatever surface it’s driving on, it lowers front and brings the third wheel into contact with the surface, spinning the robot around until both front wheels are back on the surface.

Mechanical alternatives for electronic systems are easily overlooked, but are often more reliable and rugged in hostile environments. NASA is looking at sending a rover to Venus, but with surface temperatures in excess of 450 °C and atmospheric pressure 92 times that of Earth, conventional electronics won’t survive. Earlier in the year NASA ran a design competition for a completely mechanical obstacle detection system for use on Venus.

[gzumwalt] is a very prolific designer on ingenious 3D printed mechanical devices. This mechanism could also be integrated in his walking fridge rover to explore the front of your fridge without falling off.

19 thoughts on “A Mechanical Edge-Avoiding Robot

  1. gzumwalt’s work is always fireeee. From his desktop illusions to illusions to the fact that he’s posting alot of his projects here on hackaday.io, he’s a treasure trove of inspiration!

  2. That’s nice, but you censored the comments relating to NASA and the Venus rover, so what are we supposed to do here then?

    It would be very helpful if you would specify at the end of the article what opinions and points of view are allowed, so we could avoid wasting time.

  3. Does the car avoid falls only in the clockwise direction? Or is there a mechanism to reverse the spin of the correcting wheel? Or maybe it just forces the whole car back into clockwise motion dragging both front wheels across?

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.