This is the kid version of an experimental “passive dynamic” robot from Cornell University. The original was built of Tinkertoys. Image: Kathy Ceceri
The popular image of robotics research involves big budgets, state-of-the-art technology and the latest materials. But in fact, a lot of cutting-edge research is done on the cheap, using things you probably have around the house. Coming up with ways to build simple, inexpensive prototypes makes it possible for researchers try lots of variations quickly and easily. Once perfected, these designs can be applied to more complex machines – although some researchers are looking into low-tech robots as an end in themselves!
Having spent the last year working on a kids’ book of simple robotics projects, I’ve been fascinated to discover how many robotics innovators are using everyday crafts materials and basic components in their work. When I started, I despaired of finding “cardboard-and-duct tape” type projects that kids would still find impressive. Boy, was I wrong! With just a little tweaking and substitution, I was able to adapt many of these real experimental robots into projects kids can readily do at home.
Here are a few I found particularly inspiring:
1. The Coffee Balloon Gripper
Most robot grippers look like hands. The prototype for the Universal Jamming Gripper developed by Cornell University, the University of Chicago, and the iRobot Corporation was different: a latex party balloon filled with ground coffee. The gripper works on the principle of “jamming” – when rough grains of material such as sand are loose, they flow like liquid, but when jammed tightly together, they behave like one solid mass. The Universal Jamming Gripper switches between one state and the other by means of a vacuum. To pick up an object, the gripper is pressed down onto it. The vacuum is turned on and sucks the air out of the balloon, packing the coffee grounds together tightly around the object. To release it, the vacuum is turned off and air is let back into the balloon. In tests, the Universal Jamming Gripper was strong enough to lift two large jugs of water, and flexible enough to pick up a penny lying flat on the table. Recent tests found that letting the air back in forcefully allowed the Gripper to actually “throw” an object with great accuracy. Inspired by Carlos Asmat, I included a homemade version in the book where the vacuum is created by sucking through a straw.
2. DASH, the Paper Robotic Cockroach
At the University of California at Berkeley in 2008, researchers designed a tiny six-legged robot called DASH (Dynamic Autonomous Sprawled Hexapod) that could scamper across the floor as quick as a cockroach. In order to be lightweight yet strong, the prototype for DASH was made out of folded, laser-cut poster board. Researchers discovered that the flexible cardboard actually gave DASH the ability to survive drops from the top of a building. But it also let researchers go from design to finished product in about an hour. Altogether UC graduate student Paul Birkmeyer spent about $50 on materials, including a small DC motor to power DASH to impressive speeds of 15 body-lengths per second. (Thanks to Birkmeyer for correcting the identification of the robots below. They are two different-sized versions of RoACH, a lab-mate of DASH.)
RoACH, another posterboard robotic bug from the Biomimetic Millisystems Lab at UC Berkeley. Image: http://robotics.eecs.berkeley.edu
3. The Tinkertoy Robotic Walker
The original Tinkertoy robot walker built by Andy Ruina of Cornell University. His model was the first known design to balance upright only when in motion. Image: Cornell University
At Cornell University in New York in 1998, engineer Andy Ruina built a set of walking robot legs out of wooden Tinkertoys. Ruina was doing research into designs for a passive dynamic walker, a gravity-powered mechanism that doesn’t need a motor or control of any kind. Passive dynamic walkers don’t just save energy, they actually look more natural – sometimes eerily so. For my book I was able to simplify Ruina’s already-simple materials even further. My Mini Robot Walker, which I’ve been sharing with kids at workshops this summer, uses folded card stock, bamboo skewers, peel-and-stick craft foam and wooden beads. Here’s one from a recent workshop at the Schenectady Museum:
4. Bicycle Tube Inflatable Robots
The Ant-Roach “pneubot” is like a giant beach toy you can take for a ride. Image: Otherlab.com
Engineer Saul Griffith of Otherlab in San Francisco designs inflatable robots called Pneubots that look like giant blow-up beach toys. Griffith built the first prototype out of a rubber bicycle tube for $5. Later models were made of thin fabric. They included an almost-life-sized elephant, dinosaur and octopus. His six-legged Ant-Roach is a cross between an anteater and a cockroach. It’s big and strong enough to hold two adults on its back as it walks along, but light enough for one person to carry. According to Griffith, the playful creations are really serious research projects. He sees the low cost and lightweight, yet safe and strong robotic designs being used for artificial limbs or walkers. The Otherlab project Howtoons, the popular comic pages that illustrate DIY projects for kids, shows you how to make wearable pneumatic muscles using the same principles.
5. The Cardboard Tweenbot
An experimental social robot-slash-art project, made of cardboard. Image: tweenbots.com
In 2008, New Yorker Kacie Kinzer created a cute cardboard “robot” that was half art project, half social experiment. She set her little Tweenbot loose in city parks, carrying a sign asking for help to get to the other side. Many people stopped to turn the robot in the right direction or fix it when it got stuck. One gave it a ride across the park on his bike. A few even tried telling it where to go – even though it was clearly just a cardboard box with a motor and a drawn-on face. Kinzer called her social robot project a way to make humans act more like humans. Unfortunately, a Kickstarter campaign to manufacture Tweenbot kits failed to reach its funding goal. Personally, I hope that’s not the end of the Tweenbot project — and in my book I encourage kids to come up with their own Tweenbot-type experiments. To me, when it comes to developing a sophisticated robotics research project with the most basic materials possible, Kinzer’s Tweenbot is a winner all the way!
This post was adapted from my book Robotics: Discover the Science and Technology of the Future, published by Nomad Press.
