What the heck are these?

[Joe]

Check out this photo of a bot at the recent Robo-One competition. There are a few other photos of the same bot in this folder, but this is the best close-up.

My question: what the heck are those boxes he's using where servos would normally go? I suppose there are probably servos inside, but then again, maybe not... anyone care to speculate?

Wrapping servos in a couple of standard boxes that provide an idler horn and several useful shapes might be a good way to organize a bot. Also notice the almost complete lack of visible wires. Neat!

Cheers,
- Joe

[hivemind]

thatd be a double knee joint, best used in robo-one robots for hopping or very quick walking. The RB1000 uses this design, and im presuming the lack of wires would mean daisy chain, so most likely RS-232, but perhaps 485.

It is definitely the best way to increase knee speed with limited servos.

[Joe]

thatd be a double knee joint, best used in robo-one robots for hopping or very quick walking.

Well yes, but I wasn't asking about that box in particular -- but rather, the boxes in general. The whole robot is made of them. So what do you think this builder has done? Made boxes that wrap around standard servos -- and if so, why? Or do these boxes not contain servos at all, but just a custom combination of motors, gears, and encoders?

This is the home-built forum; I'm just looking for informed speculation from you experienced home-builders.

Thanks,
— Joe

[Joe]

and im presuming the lack of wires would mean daisy chain, so most likely RS-232, but perhaps 485.

Daisy chain would still require at least one cable -- but check out this view, and this one. I'd swear there are no wires connecting these actuator boxes at all! You can pretty clearly see the gaps between the torso and the shoulder box, or between the hip and knee, and... no wires.

But of course that's impossible; even if the control signals were Bluetooth or some such, he'd still need to distribute power... unless each box contained its own batteries as well... which would be bizarre. But remotely possible.

Of course it's probably more likely that either (a) this bot is in a half-assembled state, and he'll be plugging the cables in any moment, or (b) the cables are very neatly tucked away on the inside of the connecting brackets. Still, it's fun to think about!

Best,
— Joe

[RedFoxDude]

I have wondered about Omnizero's wiring myself. I can't see the wires on the older ones either. I think that the boxes are just plates that go on the sides of the servos so that it looks better. I looked closely at this picture and I think I found some things that may be wires.

In the enlarged parts i made the things that I think are wires red. Maybe those are some wires? Hard to say.

Red

[DerekZahn]

This builder is a master! I am borrowing some ideas from that robot (OmniZero) for the one I'm building now (but less sophisticated of course). I believe the secret to the wiring is that it goes through the idler axes, and is then covered by plastic as it goes from "box" to "box". Have a look at this:

http://www.1mm.jp/m/robo20060710b.jpg

And in this one you can see the wires coming out of the shoulder joint:

http://www.1mm.jp/m/robo20060317a.jpg

Beautiful stuff!

[hivemind]

Yes, you are quite correct DerekZahn, nice views. A way to keep large bundles of wire from view (such as Kondo or even the RN-1 despite being nicely distributed) is the daisy chain, but from the looks of this picture (referenced by DerekZahn)
it would seem that the Omnizero doesnt use this system. Using the daisy chain would make this even cleaner and easier to work with. Either way, no cut wires.

Great robot indeed, but still has to have wires

[Joe]

This builder is a master! I am borrowing some ideas from that robot (OmniZero) for the one I'm building now (but less sophisticated of course).

Oh, so this is the famous OmniZero! I'd heard about it, but never seen it (or didn't recognize it when I saw it) before. Thanks for the identification.

http://www.1mm.jp/m/robo20060710b.jpg

Wow! How does a home-builder go about making an enclosure like this? I understand how to draft and laser-cut plastic, but these pieces are three-dimensional — there are holes in the sides, and various indentations and protrusions on the inside to firmly mate with the servos. To have a part like this made on e-Machines would cost a fortune. Any suggestions?

As you say, this robot is beautiful. I see it even has stereo speakers! I'm humbled — it will be a long time (if ever) before I catch up with to this level of building. But we can aspire, can't we? I look forward to seeing how you adapt some of these ideas to your own bot.

Best,
— Joe

[DerekZahn]

Wow! How does a home-builder go about making an enclosure like this?

It's not going to be easy. Even with a sophisticated milling machine I don't know how to reasonably get those tight internal corners. Perhaps a wire EDM machine could do it. That approach is not feasible for most home builders.

Here's an idea I was thinking of though: Suppose you use some sort of modeling clay or plastic or whatever. Then one could press the servos into it. Let it dry, then file/sand/mill the result so the dimensions are exactly as desired. Then use the result as a template for making a mold, then mold the final pieces out of plastic. With determination and a willingness to learn how to mold plastic I think it should be within the reach of a dedicated home builder, but it's certainly not easy!

[Joe]

Here's an idea I was thinking of though: Suppose you use some sort of modeling clay or plastic or whatever. Then one could press the servos into it. Let it dry, then file/sand/mill the result so the dimensions are exactly as desired. Then use the result as a template for making a mold, then mold the final pieces out of plastic. With determination and a willingness to learn how to mold plastic I think it should be within the reach of a dedicated home builder, but it's certainly not easy!

That's probably the most practical approach. OmniZero has a lot of other plastic parts that are probably molded too — all those curved panels and so on. I've research home plastic molding a bit, and it's all doable, but as you say, not easy. There are some great instructional videos online at http://tapplastics.com.

Best,
— Joe

[MYKL]

These are great photos of Omnizero. Does anyone know what servo-motors are used in those boxes?

I havn't been able to dig that up anywhere yet...

^_^

[beermat]

Isn't OmniZeros owner/builder associated with one of the bigger servo firms? I think that takes him away from the 'home builder' category, given the tools and resources he can pull from his professional life building these robots under the pretext of research, advertising, etc. ?

This is not to take anything away at all from the OmniZero series, they are truely awesome and innovative robots, and my personal favourites. I wish, like others, I could get more detailed info on this other than videos on Robots-dreams.com and some online photos. Whilst OmniZero is the 'Ferrari', some of technology or techniques could trickle down to us more humble home builders!

[Robo1]

about the casting.

my father uses a very simple technic to cast models of things. it's quit simple but something that couls be useful is that he case metal models makes a model out of clay then sets it in silicon like sunstance then castes with a metal with a low melting point. have try it my self but my dad can make some really detailed models using this technic.


~edit

once you have case the object so that you servos set nicely in side you can the machine the out side and have a very professional lookin product you would only need one flat sheet metal to cover the hle that gets the servos in position. (could even file it down.0


bren

[limor]

There's a popular technique for forming plastic parts using your home vacuum cleaner..

http://www.warmplastic.com
http://users2.ev1.net/~jimbobwan/art09.htm
http://www.studiocreations.com/howto/vacuumforming/

[tempusmaster]

This builder is a master! I am borrowing some ideas from that robot (OmniZero) for the one I'm building now (but less sophisticated of course).

Oh, so this is the famous OmniZero! I'd heard about it, but never seen it (or didn't recognize it when I saw it) before. Thanks for the identification.

http://www.1mm.jp/m/robo20060710b.jpg

Wow! How does a home-builder go about making an enclosure like this? I understand how to draft and laser-cut plastic, but these pieces are three-dimensional — there are holes in the sides, and various indentations and protrusions on the inside to firmly mate with the servos. To have a part like this made on e-Machines would cost a fortune. Any suggestions?

A little background:

1- Maeda is a pro. He works for Vstone, and is one of the members of TEAM OSAKA (RoboCup).

2- The current OmniZero is the 10th robot in the "Omni" series that he's designed and built. On average he has redesigned his robot every six months for the subsequent ROBO-ONE competition. If you compare his early robots with the current version the evolution is pretty striking. He keeps trying, making mistakes, learning from them, and evolving.

3- Most of the bodies for robots like this, including Dynamizer (Sugiura) are designed in 3D on CAD systems and then machined using a small Roland milling machine.

Other builders here in Japan use less sophisticated techniques but still produce excellent results. Nao Maru, who won the ROBO-ONE 10 competition, uses vacuum formed plastic for the King Kizer series body shells and put together most of the equipment buying stuff at the 100 yen (dollar) store.

Here's another example:



The 8 inch tall robot on the left is a full custom design completely built by hand without any special machine tools by a couple students at the university near us. The one on the right was made out of wood. Asurada (Layred-X) built his ROBO-ONE J (August) entry by cutting and heat bending sheets of clear plastic.

It's really dependent on how much time, effort, creativity and dedication you want to put into it. Having sophisticated equipment helps, of course, but isn't a absolute requirement.