Let's Make Robots!

I've spent quite a bit of time on the mechanical design on this robot, maybe more then was strictly necessary since I used this opportunity to learn SolidWorks, and since all the parts are laser cut, absolutely everything must be modeled.

All the body pieces are laser-cut, excluding the obvious bolts, threaded rods, and electrical parts.

The pictures you see here are from the assembly of the 3rd prototype and so far I'm pleased with how it’s turned out. I've successfully driven it around on my coffee table, but very little electrical work has been done on it yet other then a closed-loop test script.

I’m planning to publishing the plans open-source style as soon as I’m happy with everything. there’s also the possibility of a kit in the works.

Videos and more details soon, so stay tuned here and on 4volt.com/blog.

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Update: Now with video! http://vimeo.com/4221721

I can't seem to embed my vimeo video for some reason, sorry! 

If you are intrested in the source files to cut your own copy, see 4volt.com/projects/jansen/

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I make a project like this one some time ago to my semester school project but by some rason my robot finish walking like a frog XD

maneuver's picture

Is the plastic brittle? I notice you're running the robot on a soft mat, would it crack/break on a stone floor?

Do you have your own laser cutter? Does that mean I can buy those leg assemblys from you?

Oh, and like Rik said; That tool handle dipping rubber thingy needs a write-up with links in the component section.

The plastic is somewhat brittle, if you dropped or stepped on it it would probably shatter. But, it's tipped over many times and I haven't broken any parts in this build or any of my tests on various surfaces.

The reason I was running it on a smooth surface is on carpet the legs tend to get caught in the fibers. Also the first table was covered in random paint so I threw a cloth backdrop over the top.

If you are interested in buying just a plastic set, I'm selling copies of this version for $35 (USD), for about 100 plastic peices. Mostly I'm trying to fund my hobbies, not really trying to make any money. Check out my site for more on that.

I'll be sure to write up somthing in components about that rubber dip, it's pretty handy.

rik's picture

Thanks. Liking the music.

It moves beautifully, as expected. Too bad about the whining of the servo gears. If I knew a good cheap solution for that, I'd be a rich toymaker.

I noticed some oscillation going on in the long threaded axle rods. Some of that springy action seems to be eating up the efficiency of the legs. Also makes the creature stand less stable on the ground. A plate at the end of the rods, connecting the two, would probable help stiffening the construction.

The two big flaws in the design so far I think are that the center of gravity is two high, and there's not enough legs to get smooth motion.

The rods are actually pretty solid in general, on that one shot that's looking at the legs i'm holding it by hand so it looks a little springy like you said. Most of the beach walkers that Jansen desiged seem pretty flexable and walk well, but they also have many more legs.

With the few legs I have, they seem to pogo into the ground while walking and bounce the front end up. I think with more legs on the ground that would be minimized.

All stuff for the next version I suspose...

Gareth's picture

I have only seen Paper versions of this so i am really intrigued to see how the motion works.

I very much like the optical effect of the lazered Plexi-glass - veryvery neat.

 

NB. you are using Micro servos (one straight and the other opposing) - i had a problem once with this micro servo config as i could not match the speeds (as they favour to be driven in one direction-must be something to do with the internal mech)- normal (big) servos dont seem to have this problem.

I was able to get the servos rotating at the same speed with a software fix, the servo library I use allows you to adjust the max pulse mills that compensates. I may still switch to regular sized servos, but for now the micros seem okay.
OddBot's picture

I've been following your progress since you first started on this site. It's nice to see it all coming together. I think it needs one of those signs on the back that you see on trucks.

"WIDE LOAD"

guibot's picture
Awesome!
Can´t wait ti see it moving!!!
I would love to know more about your laser cutter, did you buy it? or did you make it yourself? keep it up ;)
McDuino's picture
i love the walking movement of the legs. must have taken some time to make them move so smoothly.