Robot w/ many servos
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Posts: 46,084
Greetings!
My daughter and I have decided to build a robot. We are intrigued by
the design of Lynxmotion's Hexapod 3, and have a few questions:
What are the power requirements for 18 servos? Lynxmotion uses HiTec
HS-85BB's on theirs, and they do indeed seem to have the most torque
for the size/price.
We have decided to use a BS2SX, with 3 Scott Edwards SSC's. If we
operate all four of those on the same 9v battery, how long will the
battery last?
Lynxmotion doesn't seem to have fleshed out the Hexapod 3, not
offering any electronics or programming. Does anyone have any
experience with this robot, or one like it?
If anyone has any helpful information, hints, or advice, it would be
greatly appreciated.
Regards,
RK
My daughter and I have decided to build a robot. We are intrigued by
the design of Lynxmotion's Hexapod 3, and have a few questions:
What are the power requirements for 18 servos? Lynxmotion uses HiTec
HS-85BB's on theirs, and they do indeed seem to have the most torque
for the size/price.
We have decided to use a BS2SX, with 3 Scott Edwards SSC's. If we
operate all four of those on the same 9v battery, how long will the
battery last?
Lynxmotion doesn't seem to have fleshed out the Hexapod 3, not
offering any electronics or programming. Does anyone have any
experience with this robot, or one like it?
If anyone has any helpful information, hints, or advice, it would be
greatly appreciated.
Regards,
RK
Comments
much larger power source like "C" cells or rechargeables like the ones for
RC model racers.
Richard
Original Message
From: "rk_az" <rk_az@y...>
To: <basicstamps@yahoogroups.com>
Sent: Friday, December 14, 2001 10:29 PM
Subject: [noparse][[/noparse]basicstamps] Robot w/ many servos
> Greetings!
>
> My daughter and I have decided to build a robot. We are intrigued by
> the design of Lynxmotion's Hexapod 3, and have a few questions:
>
> What are the power requirements for 18 servos? Lynxmotion uses HiTec
> HS-85BB's on theirs, and they do indeed seem to have the most torque
> for the size/price.
>
> We have decided to use a BS2SX, with 3 Scott Edwards SSC's. If we
> operate all four of those on the same 9v battery, how long will the
> battery last?
>
> Lynxmotion doesn't seem to have fleshed out the Hexapod 3, not
> offering any electronics or programming. Does anyone have any
> experience with this robot, or one like it?
>
> If anyone has any helpful information, hints, or advice, it would be
> greatly appreciated.
>
> Regards,
> RK
>
>
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>
>
> We have decided to use a BS2SX, with 3 Scott Edwards SSC's. If we
> operate all four of those on the same 9v battery, how long will the
> battery last?
The bs2sx and 3 ssc's together will draw about 90 ma. About 1-3 hrs
(depending on battery capacity) before it reaches the regulators
dropout point. I would use 6 AAA, or AA if the weight is not to much.
The servos will need larger batteries
Rick
Something you should also be careful of if you are
going with the Hexapod 3, since it uses the HS-85BB
Servos, make sure you do NOT OVERPOWER them, usually
you can get away with hooking up a 7.2v NiCad pack
with normal servos, however I have talked with people
who have burned out the HS-85BB servos this way. No
more than 4.8vDC should be applied to power these
servos otherwise you will burn them out very easily,
and they are expensive to replace. Just my 2 cents.
--- rckbrwn <mycomminc@a...> wrote:
> --- In basicstamps@y..., "rk_az" <rk_az@y...> wrote:
> > We have decided to use a BS2SX, with 3 Scott
> Edwards SSC's. If we
> > operate all four of those on the same 9v battery,
> how long will the
> > battery last?
>
> The bs2sx and 3 ssc's together will draw about 90
> ma. About 1-3 hrs
> (depending on battery capacity) before it reaches
> the regulators
> dropout point. I would use 6 AAA, or AA if the
> weight is not to much.
> The servos will need larger batteries
>
> Rick
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed.
> Text in the Subject and Body of the message will be
> ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
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Lynxmotion. This kit was one of the best kits I have every built. The nine
volt battery last for a couple hours and the 7.2 volt RC battery last for
about 1 hour. The servos supplied work very well. I would without
hesitation recommend this kit.
Just to respond to some of the replies:
Of course the 9v battery wouln't be used to power the servos. I
meant only to power the stamp and ssc's with it. I reckon I could
always draw their power from the same source used for the servos.
Any idea why the HS-85BB's in particular are not recommended for over-
powering? The Lynxmotion site said the same thing. Does anyone know
of another high-torque micro that would be better? Or should I use
bigger servos and build a bigger robot to accomodate them?
We actually don't plan to buy the Hexapod 3 kit. Partly because they
don't have any electronics or programs available for it yet, and
partly because it is on the pricey side. I think we can build it
ourselves, and buy servos elsewhere much cheaper (sorry Lynxmotion!).
Thanks to those who responded, and any other input is welcome.
Regards,
RK
compared to standard servos, but are a fit pricey. I would think for maximum
longevity, at minimum you would want standard ball-bearing servos, and
possibly metal gears as well. If you need 8 servos you will wind up spending
most of you budget on them and not the control stuff.
At any rate, assume that you will use 4 AA batteries or a 7.2 NiCad pack and
start comparing torque & weight specs for all the different servos that will
work at these voltages. Be sure they don't require more current than your
battery pack can supply.
Original Message
> Of course the 9v battery wouln't be used to power the servos. I
> meant only to power the stamp and ssc's with it. I reckon I could
> always draw their power from the same source used for the servos.
>
> Any idea why the HS-85BB's in particular are not recommended for over-
> powering? The Lynxmotion site said the same thing. Does anyone know
> of another high-torque micro that would be better? Or should I use
> bigger servos and build a bigger robot to accomodate them?
>
> We actually don't plan to buy the Hexapod 3 kit. Partly because they
> don't have any electronics or programs available for it yet, and
> partly because it is on the pricey side. I think we can build it
> ourselves, and buy servos elsewhere much cheaper (sorry Lynxmotion!).