Browsing around today, I saw this little kit on kickstarter called Kinetic Creatures. These flat packed models are made from cardboard and can be assembled without tools. Their mechanical legs are operated either by a simple cam that you turn by hand or by a motorized attachment. I love the basic idea here. This is the kind of thing that my 6 year old would really enjoy doing that also serves to get him into making things (he’d probably insist on motorizing it with scraps, he collects dc motors and has quite a collection).
I did notice that they mentioned using it as a robotic platform, adding custom electronics to the empty space allowed in the body of the animal. This initially got me quite excited, thinking that I could, for $30 have a 1 foot tall quadruped platform that looked awesome, then I realized it can’t turn. I guess I’ll have to hack it a little bit to put separate drives in for each side. That would be a cool upgrade they could offer.
Have any of you tried to do turning with a set of only 4 [jansen] legs before?
Cool laser cut thingies! But I don’t like precut kits much, it becomes cool when you can make your own changes to the design, and this project doesn’t allow that.
They say they need 2 hours of laser cutting time to make one of these, that’s ~300 USD (if you charge 2.5 USD per minute)? Damn…
What a medium-creative idea. The mechanic was (as written) invented by Theo Jansen. Es build his giant machines with multiple legs so it can have a fairly stable move.
Now what did those two kickstarters? They Add a Giraffe-Cardboard to the center and let them hobble forward. What kind of accomplishment is that? You can see that the creatures just wobble from one leg to the other. Didn’t say see that it doesn’t work with just 4 legs?
A Jansen Walker is not likely to be turning anytime soon. Unless, you power the pairs of legs independently.
Thanks for the post!
I haven’t tried making them turn yet, but I’m pretty sure they will. The challenge is that in order to walk normally, the legs have to be in phase. That means that you have to keep track of their rotation, maybe an optical sensor and dots on each leg’s main gear. My strategy will be to put some tape on the feet to allow them to slide a bit, then control the legs independently by either stopping one side and moving the other, or running them both in opposite directions. They won’t be as easy to steer as a wheeled robot, but they are a relatively stable, light, and easy to build walking platform.
How about having a front and rear motor for two half-walkers (or a clever mechanism I can’t just think up right now), and a servo-powered pivot in the center of the critter? Leg movement could continue as usual.
Using 3 separate stepper-motors, you can power the fore and hind legs, and make a torso (joint) by using another stepper. I would also suggest making a copy of it in plastic (like those on plastic clear folder) to make it more rigid and less wear and tear ‘cuz cardboard won’t last that long.
Seems like it’s basically a scaled down Strandbeest, too small to run on wind power. Anyone who doesn’t want anything more than a desk toy could use a wind-up mechanism instead of an electric motor to power it.