23 DOF Project. Which platform? AT-01, Bioloid or KHR-1HV

[NullARC]

I'm sure, by now, most of you have heard of the Cycloid II by Robotis, from the same people who brought us the Bioloid. (if not, look here http://www.tribotix.com/Products/Robotis/Robotis.htm )

If you have seen the videos of this biped you also know that it has 23 DOF and is capable of some great movements. (videos: http://www.tribotix.com/Videos/Videos.htm click the 'Robotis' tab at the top of the page) Unfortunately it carries a reported $20,000 USD price tag! Well out of the reach of most hobbyists / experimenters budget.

I would like to build a biped similar to the Cycloid with 22 or 23 DOF. This brings me to the question, which robot kit would be the best platform for this project? The Manoi AT-01, Robotis Bioloid or the new Kondo KHR-1HV?? I guess the most important aspects would be (1) servo torque, to carry the additional weight of 4 to 6 additional servos. And (2) ease of construction with existing parts. (3) I also want it to be powerful enough to execute EMMA-U0A's 'standing up' maneuver. It can be viewed in the video at the bottom of this page: http://www.robots-dreams.com/2006/12/em ... .html#more VERY COOL MOVE!!


As I see it, here are the pro's and con's of each biped for this application:


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Robotis Bioloid:
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Pro's:

1. Similar construction method to Cycloid. (uses same bracket system, though in aluminum)
2. Additional servos only roughly $50.00 USD.
3. Servos have 300 degree rotation range.
4. One has been built already, though it has not been tested yet. Look here: http://forums.tribotix.info/forum1/54.html
5. Comes with 19 servos out of the box.
6. Great price Approx. $900.00 USD.
7. Servos created for robotic use, with many more features than other standard biped kits.

Con's:

1. Currently no gyro support for added stability.
2. Relitively low torque servos (16.5 kg/cm). Though higher than 1HV & AT-01.
3. Higher torque servos (DX-117's 28 kg/cm) are approx. $195.00 USD. ouch!
5. Would need M5 controller board if upgrading to the 14.4v DX-117 servos. ?? not sure ??

Additional considerations:

The little brother to the Cycloid II, the Cycloid III, uses DX-113 servos listed at only 10.2 kg/cm and seems to work fairly well though obviously over matched in a bout with a Cycloid II. (video of match can be found at link above) So servos with a torque of around 10 to 15 kg/cm might be adequate.



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Manoi AT-01:
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Pro's:

1. Can be upgraded to 21 DOF fairly easily. (tempusmaster states that manual has instructions for adding 4 DOF arms / legs)
2. Has gyro support.
3. Additional KRS-4024 HV servos only roughly $60.00 USD.
4. Can be easily upgraded to KRS-4014HV servos for a massive 40 kg/cm torque!
5. Servos have 260 degree rotation range.

Con's:

1. KRS-4014 servos cost approx. $145.00 USD. again, ouch! (though less than DX-117's)
2. Servos only have a torque rating of 10.5 kg/cm. Is that enough??
3. Only comes with 17 servos out of the box.
4. $1,500.00 USD Price.

Additional Considerations:

Has the advantage of being created by some of the best minds in the RoboOne / biped world!!



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Kondo KHR-1HV:
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Pro's:

1. Comes with 19 DOF out of the box. (with 2x KRS-4024HV servos)
2. Has gyro support.
3. Additional KRS-788HV servos only roughly $50.00 USD.
4. $1,091.00 USD price. (according to Trossen Robotics Blog http://blog.trossenrobotics.com/index.php )

Con's:

1. KRS-788HV servos only have a torque rating of 10 kg/cm.
2. Servos can't be upgraded to higher torque.
3. Additional frame pieces would have to be manufactured.
4. Who knows when Kondo might release it??



Ok, that's how I see it. I can't make up my mind though!!

This is where you come in! If I have missed something, or something is wrong, PLEASE let me know.

And finaly WEIGH IN on your vote for the best platform for this project and why! I WANT YOUR OPINIONS!!

Thanks for your time and expertise everyone!!

- Marc

P.S. - I have posted this in the Kondo & Bioloid discussions for a broader range of opinions. Sometimes 'Kondo guy's' just say Kondo and sometimes 'Bioloid guy's' just say Bioloid. Know what I mean?!?!

[Joe]

I'd say you've summarized the pros and cons pretty well. From what I've seen, 10 kg cm is just barely enough for a humanoid robot — and may easily slip into the not-enough range if you start adding more stuff. 16 kg cm is, well, 60% more strength, plus the Bioloid servos have all those other nice features, and $45 for them is a great price. I'd say go with that.