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View Full Version : Biped: Fork in the road



Sienna
06-05-2008, 10:19 PM
I have 6 HSR5990TG servos right now. I want to build a 7 DOF per leg biped. (one DOF will be taken care of by a less expensive servo, probably a 5645). (the additional DOF is a low profile axis, something I don't think Bioloid has...) In addition, I already have all the SES stuff for one leg.


I figure that in order to complete the other leg, it will cost about $900. A Bioloid kit is also $900.

Which route makes more sense to go down?

Do I finish buying servos for a SES based 5990 design? Or do I scrap that entire idea and go for a Bioloid design?

I am not interested in robot combat if that helps, I more want something that won't have problems walking on a pile of laundary for instance. (a.k.a., mars for indoor robots :P)

Thanks for your opinions!

LinuxGuy
06-05-2008, 11:49 PM
I have 6 HSR5990TG servos right now. I want to build a 7 DOF per leg biped. (one DOF will be taken care of by a less expensive servo, probably a 5645). (the additional DOF is a low profile axis, something I don't think Bioloid has...) In addition, I already have all the SES stuff for one leg.
What design are you going with for the legs?


I figure that in order to complete the other leg, it will cost about $900. A Bioloid kit is also $900.

Which route makes more sense to go down?
Well, you already have quite a bit invested in SES stuff. Consider that. I bet you have already invested more than the price of a Bioloid Comprehensive Kit in all the SES stuff you have. It does not take long to accumulate a large SES investment.


Do I finish buying servos for a SES based 5990 design? Or do I scrap that entire idea and go for a Bioloid design?
It really depends whether you are itching to try "something completely different", or stick with what you already have and add on to that. There is a lot that can be done with the SES, and I've shown several custom and even unusual designs that can be built, including for biped, hexapod, and octapod configurations.

8-Dale

4mem8
06-06-2008, 12:33 AM
Hello Sienna, I think I would go for the Bioloid, I do not own one but I think these bots are really neat and have a lot of potential. When I have finished my J5 like Tyberius's one I may go down this route and get one. Hope this has helped in your decision.

metaform3d
06-06-2008, 01:50 AM
It's odd, but as a software person I feel that custom hardware is often easier. I'm sure that I could get good results from kits, but I also know that once I get into them deeply enough to be interesting I know that the design of the software will make me angry. I will be able to do better, and yet because I don't have control of the lowest levels of the system (because I'm a *software* guy not a freaking hardware guy) I won't be able to make the changes that I want.

It may be a personal flaw, but I'd always build enough from scratch that I have complete control over the software. Having to live in someone else's flawed architecture is my idea of hell.

YMMV.

Adrenalynn
06-06-2008, 01:57 AM
I'll go one step further than Meta:

Give me custom one-off hardware or give me death. Just as long as it's MY ugly custom one-off hardware...

LinuxGuy
06-06-2008, 10:47 AM
I'll go one step further than Meta:

Give me custom one-off hardware or give me death. Just as long as it's MY ugly custom one-off hardware...
I agree completely! However, I am a software sort of guy like Meta, and I have difficulties with mechanical stuff, so I would prefer to not have to deal with that at all and just do software. I can easily master any programming language I may want to or need to work with.

8-Dale

DresnerRobotics
06-06-2008, 11:17 AM
If those 6 HSR5990TGs are going to be salvaged from your beautiful Tripod, I whole heartedly disagree in going the SES route :D

That said- I'm going to go Bioloid for sure when I build my first biped. The Dynamixels are just too cool to not tinker with. I'll probably eventually move to aluminum brackets, but I've heard the plastic ones are quite solid as is.

Sienna
06-06-2008, 12:02 PM
No, the servos are not going to come from Amy :P She has 12 5645s atm. (There wasn't enough weight on the tripod to cause the 5990s to act normally, so they twitched)

Robotguy: I have most of it built for one leg already. I will photo it this weekend.

>>>>> Give me custom one-off hardware or give me death. Just as long as it's MY ugly custom one-off hardware...
*giggles*

I actually love the hardware side. (this coming from the CS major who hates coding... :look)

Hmm... so far if I am counting right, the vote is 3 to 3?

LinuxGuy
06-06-2008, 12:15 PM
I actually love the hardware side. (this coming from the CS major who hates coding... :look)
If we didn't live so far apart, I could code and you could build. It could really work out well if not for being on opposite coasts.

I don't think I actually voted, so I would go with staying with the SES for now. You've seen some of the stuff I have designed using the SES, which I think are unique designs - including my new 6DOF biped leg design. I still have to design arms and head for it, though.

8-Dale

tom_chang79
06-06-2008, 02:58 PM
I have a Bioloid kit myself. Software development is not any more difficult then say an SES-based bot. If you really want, you can control the AX-12+ just like any other servos, except instead of controlling the PWM, you control bytes being sent in through the TTL-serial.

Here's a suggestion with the 6 5990TGs: Super torque-Brat out of them! Or you can possibly make a robotic arm for it, a very robust and strong arm!

The Bioloid is an awesome kit, the AX-12+ is an awesome actuator. They are packed with so much features inside each of them that it presents more options when programming it, like load sensing and feedback (Check out Alpha's creations)...

My vote would be on the Bioloid kit, but having 6 5990TGs laying around, I'd be tempted to buy 6 more and make a 6DOF Biped Scout (or a 209)

Sienna
06-07-2008, 07:08 PM
That seven DOF leg design....

After several iterations, I found that the original design added way to much height for its benefit, so I scrapped that one and rebuilt the leg into this, which performs much better from a freedoms vs height perspective:

http://forums.trossenrobotics.com/gallery/files/1/6/8/5/sevendofleg_01_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=357&c=3&userid=1685)

http://forums.trossenrobotics.com/gallery/files/1/6/8/5/sevendofleg_02_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=358&c=3&userid=1685)

http://forums.trossenrobotics.com/gallery/files/1/6/8/5/sevendofleg_03_thumb.jpg (http://forums.trossenrobotics.com/gallery/showimage.php?i=359&c=3&userid=1685)

Wingzero01w
06-07-2008, 10:01 PM
Wow how big is this robot gonna be!? Those are some huge legs.

darkback2
06-07-2008, 11:14 PM
I would suggest you stick with the investment you have already made. I guess I just feel like you will end up unhappy with a kit, given that it will have limitations that you can't easily get around. While going the custom route might be harder, you will probably have a better project in the end.

DB

Droid Works
06-08-2008, 12:56 AM
Wow how big is this robot gonna be!? Those are some huge legs.

here is a vid of the bot when it is finished...lol

YouTube - Robot Walking

Sienna
06-08-2008, 01:29 PM
Droid!!!! How am I supposed to take over the world if you insist on showing my secret future plans!! :P

tom_chang79
06-09-2008, 09:48 AM
Sienna has six 5990TGs

Tom has ZERO 5990TGs

/jealous

Sienna
06-09-2008, 06:07 PM
Tom has many working 'bots.

Sienna has no working 'bots.

/jealous back

sthmck
06-10-2008, 11:21 AM
I would stick with the ses robot considering the fact that you are already halfway done. In my case I tend to enjoy having something that is a little different then everyone else. Im not taking anything away from your other option, I think that it is a very nice kit. I would just go with a more custom design. Thats my 2 cents