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From: rstevew@armory.com (Richard Steven Walz)
Subject: Re: Biped robot designs & ideas (Question)
Organization: The Armory
Date: Tue, 17 Jan 1995 15:34:54 GMT
Message-ID: <D2K3A7.Azt@armory.com>
References: <3evm76$84n@newsbf02.news.aol.com> <yzhu.790268016@saturn.acs.oakland.edu> <nagleD2IH4M.4zz@netcom.com> <yzhu.790285128@saturn.acs.oakland.edu>
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In article <yzhu.790285128@saturn.acs.oakland.edu>,
yzhu <yzhu@saturn.acs.oakland.edu> wrote:
>nagle@netcom.com (John Nagle) writes:
>Kid.
>
>
>>yzhu@saturn.acs.oakland.edu (yzhu) writes:
>>>Being kicked around are theoretical discussions about static or dynamic
>>>motion and control. Some of them are quite impressive. But from control
>>>point of view, by my opinion, there's a thing that cannot be overcome by
>>>existed theory, which is that the error allowed to foot
>>>position,velocity and acceleration is zero in some direction, given a
>>>traditional controller. Now imagine a feedback controller can handle
>>>only part of its input  and you'll reach similar conclusion as the
>>>gentleman did as the following.
>
>>    Huh?
>
>>    Read Raibert.  One, two, and four-legged running machines have been
>>built.  The control algorithms aren't complicated.  And yes, you can
>>give his machines a small kick and they recover just fine, even if they
>>have to hop a few steps backward.
>>    					John Nagle
----------------------------------
I wrote the disparaging remarks. Yes, there are some wonderfully heavy and
high powered tethered bipeds that walk, and if you have a $100K grant you
can build one too! But if you are a hobbyist roboticist or even a small
maker of commerical robots, this technology is out of your reach. The one
legged robot is the cutest but I have not seen it run without a very large
computer and power supply and a heavy multi-conductor tether! The others do
a LOT of falling down. The science shows on the science-Pop network,
Discover channel, make it look good by selective videography, but these
things are not at all ready and able for work quite yet, and that, kids, is
what I meant!
-Steve Walz   rstevew@armory.com

