Most readers will be familiar with the work of the Dutch artist Theo Jansen, whose Strandbeest wind-powered mechanical walking sculptures prowl the beaches of the Netherlands. The Jansen linkage provides a method of making machines with a curious but efficient walking gait from a rotational input, and has been enthusiastically copied on everything from desktop toys to bicycles.
One might think that a Jansen linkage would be beyond some materials, and you might be surprised to see a paper one. Step forward [Luis Craft] then, with a paper walking Strandbeest. Designed in Blender, cut on a desktop CNC paper cutter, and driven by a pair of small robots linked to an Arduino and controlled by a Bluetooth link, it has four sets of legs and can push around desktop items. We wouldn’t have thought it possible, but there it is.
He claims that it’s an origami Strandbeest, but we’re not so sure. We’re not papercraft experts here at Hackaday, but when we put on our pedantic hat, we insist that origami must be made of folded paper in the Japanese style rather than the cut-and-glue used here. This doesn’t detract from the quality of the work though, as you can see in the video below.
Father-and-son team [Wade] and [Ben Vagle] have developed and extensively tested two great walker designs: TrotBot and the brand-new Strider. But that’s not enough: their website details all of their hard-earned practical experience in simulating and building these critters, on scales ranging from LEGO-Technic to garage-filling (YouTube, embedded below). Their Walker ABC’s page alone is full of tremendously deep insight into the problem, and is a must-read.
These mechanisms were designed to be simpler than the Jansen linkage and smoother than the Klann. In particular, when they’re not taking a stroll down a beach, walker feet often need to clear obstacles, and the [Vagles’] designs lift the toes higher than other designs while also keeping the center of gravity moving at a constant rate and not requiring the feet to slip or slam into the ground. They do some clever things like adding toes to the bots to even out their gaits, and even provide a simulator in Python and in Scratch that’ll help you improve your own designs.
If you wanted a robot that simply moved, you’d use wheels. We like walkers because they look amazing. When we wrote [Wade] saying that one of Trotbot’s gaits looked animal-like, he pointed out that TrotBot got its working name from a horse-style gait (YouTube). Compared to TrotBot, the Strider family don’t have as much personality, but they run smoother, faster, and stronger. There’s already a 3D-printing-friendly TrotBot model out there. Who’s going to work something up for Strider?
[Theo Jansen] has come up with an intriguing wind-powered strandbeest which races along the beach with surprising speed and grace. According to [Jansen], it “doesn’t have hinging joints like the classical strandbeests, so they don’t get sand in their joints and you don’t have to lubricate them.” It’s called UMINAMI, which appropriately means “ocean wave” in Japanese.
There are only videos of it in action to go on so far, but a lot can be gleaned from them. To make it easier to keep track of just a single leg, we’ve slowed things down and reddened one of them in the banner animation. Those legs seem to be providing a push but the forward motion is more likely supplied by the sails. The second video below shows it being pulled along by the type of strandbeest we’re all more used to seeing.
What follows is an analysis and best guess about how it works. Or you can just enjoy its graceful undulations in the videos below.
This ‘beest is the natural next step after his remote-controlled walker, which we featured a month or so ago. Like that one, the locomotion comes from a pair of micro gear motors that are controlled by an Arduino Nano over Bluetooth. The pyrotechnics begin when nitinol wire cleverly strung across two lever nuts is triggered. All the electronics are housed inside a 3D-printed box that [Jeremy] designed to sit in the middle of the legs. We love the face plate he added later in the build, because those gumdrop LED eyes are sweet.
Can you believe that this vehicle of destruction began as a pile of innocent, pasta-colored pieces of kit? We dig the camouflaged battleship paint job, ’cause it really toughens up the whole aesthetic. And really, that’s probably what you want if you’re driving around a spindly beast that can just shoot rockets whenever. Let’s light this candle after the break, shall we?
We’ve seen a Strandbeest kit conversion like this before, such as this DC motor one but it’s always interesting to see how it can be done differently. In [Jeremy’s], he’s gone with two inexpensive $2.00 stepper motors. The RC is done using a keyfob transmitter with a receiver board wired into an Arduino Nano’s analog pins. He tried driving it directly off the LiPo batteries but had issues which he solved by adding a 5-volt regulator. Check out his build and the modified Strandbeest walking around in the video below.
Theo Jansen’s Strandbeest design is a favorite and for good reason; the gliding gait is mesmerizing and this RC version by [tosjduenfs] is wonderful to behold. Back in 2015 the project first appeared on Thingiverse, and was quietly updated last year with a zip file containing the full assembly details.
All Strandbeest projects — especially steerable ones — are notable because building one is never a matter of simply scaling parts up or down. For one thing, the classic Strandbeest design doesn’t provide any means of steering. Also, while motorizing the system is simple in concept it’s less so in practice; there’s no obvious or convenient spot to actually mount a motor in a Strandbeest. In this project bevel gears are used to mount the motors vertically in a central area, and the left and right sides are driven independently like a tank. A motor driver that accepts RC signals allows the use of an off the shelf RC transmitter and receiver to control the unit. There is a wonderful video of the machine zipping around smoothly, embedded below.
There’s a little problem with sending drones to Venus: it’s too hostile for electronics; the temperature averages 867 °F and the pressure at sea level is 90 atmospheres. The world duration record is 2 hours and 7 minutes, courtesy of Russia’s Venera 13 probe. To tackle the problem, JPL has created a concept for AREE, a mechanical robot designed to survive in that environment.
AREE consists of a Strandbeest configuration of multiple legs with a monster fan propelling it, and one can imagine it creeping over the Venusian landscape. While its propulsion system might be handled by the Strandbeest mechanism, it will still have to navigate and transmit data. We’re not sure how a mechanical radio wave might work–maybe like those propeller arrow-cutters that [Dain of the Iron Hills] busts out in movie version of the Hobbit? Chemical rockets that somehow don’t spontaneously ignite? Or maybe it can just “transfer all energy to life support” and AC the heck out of the radio.