Two robots face off and try to throw each other off of a table! It'll make more sense after you watch the video...
More footage from actual student-built JudoBots:
Updated version from my book Rubber Band Engineer
I call them JudoBots because of the way they seem to throw and grapple with each other during combat.
Although designed for children in grades 4-6, I think just about anyone can have fun with this. Even parents can't resist trying it out!
The bots are assembled from four components built separate from one another: the base, the stand, the arm, and the hydraulic system. The hydraulic system uses plastic syringes as pistons and water as the hydraulic fluid.
Please message me to report broken links. All of these materials are used in my other Instructables for kids, so your purchases can be used across multiple projects.
Material limitations are in place to promote resourcefulness and to reduce cost. Also, clever students can no longer pile hundreds of sticks onto their bot in order to make it too heavy to move.
You may choose to use other materials. This is what I use because I need to streamline my materials to fit with the other projects in my program, as well as keep the cost per project low.