Newbie question - how to animate a turtle?

Maybe try hacking some of the Wowee type toys like seen here: =
http://www.wowwee.com/
Depends on how big the turtle is.

As for realism, I am guessing the audience will know it's not real, no =
matter what you use as a "stand-in".

Just my 2 cents -
JCD

This should be a pretty easy project for anyone with RC experience --
what you want is just a couple of servos connected to the neck of the
turtle.  You can buy these at any hobby store, and I don't think they'd
need to be particularly powerful.  The whole electronics will consist of:

1. R/C transmitter -- a simple 2-channel analog one will do; this is
what the prop guy up in the booth will use to control the turtle.
2. R/C receiver -- goes inside the turtle, and converts the radio waves
from the transmitter to servo pulses
3. Two servos -- receive power and servo pulses, and move a little lever
arm accordingly
4. Rechargable battery -- powers the receiver and servos.

The rest is whatever armature and mechanical linkages are necessary to
make this thing look like a turtle with a moveable head, but I assume
your prop guy can handle that part.  (You could build this out of LEGO,
or Erector Set, or wood, or whatever medium you like, and then cover it
with a rubber or plastic turtle head/neck.

If you're getting down to the wire, it might be time to enlist some
help.  Your local R/C hobby store can probably put you in touch with the
local R/C group; these are usually pretty active in the summer.  Anybody
who's built an R/C car, plane, or boat will know everything needed to
make the above work, and could probably get your prop guy unstuck in a
few hours.

Best,
- Joe

--
"Polywell" fusion -- an approach to nuclear fusion that might actually work.
Learn more and discuss via:  <http://www.strout.net/info/science/polywell/>

get a real turtle, put a fake shell over its' real shell.  Hide an RC
receiver,
battery, and HV supply under the shell.  Put electrodes from the HV
supply
to the feet of the turtle, and one on its' head.  When you want the
turtle
to move, press a button on the transmitter, and it'll shock the turtle
and make
him move...

??

Why does it matter if everyone knows the turtle is not real? A stage
play
is all make believe, none of it is real. The only important question
is: Is it
entertaining :)

--
jc

I have about 40 years of experience working in theater and film, so,
believe me, I know there are cases where it doesn't matter if the
audience knows the prop is real or fake.  Without listing a dozen
examples from this show, I'll just have to ask that you trust me to
have reasons for wanting the audience to question for themselves
whether the turtle is real or not.  Many of these have to do with some
of the themes inherent in the play.  And, just to go back on my word
and give one concrete example, there is some business of one of the
characters "feeding" his pet turtle some lettuce.  If we use a very
obviously fake turtle, when that moment comes, it either draws a laugh
at the ludicrousness of it or it raises questions about the
character's sanity.  Neither are the response we're looking for at
that particular moment.

Of course, the audience realizes most of our props are fakes.  But,
when you're playing in-the-round and the audience is sitting,
literally, with their feet on the stage, the degree to which you have
to try to make your fakes seem real increases.  When you're dealing
with live entities, the problem of suspension of disbelief becomes
touchier. The next poster, RMDumse, is exactly on the same page with
our thinking...we'd like the audience to assume the turtle is fake,
then just throw in the tiniest bit of movement to make them doubt
their opinions.

Thanks to the rest for your RC advice.  We're looking to get in touch
with local RC folk (which, unfortunately, seem to be a little thin on
the ground in our area.)

You might want to try a web site like www.servocity.com.  I buy alot
of RC stuff from them.  They have transmitters, receivers, servos and
all kinds of mechanical linkages.  Their web has some very helpful
information as well.

If you call them, they'll probably line you up with everything you
need.

BRW

I think the best of surprizes ito let everyone conclude that, and
about 4 minutes in, it twitches a little. Just enough to worry them it
might not be a simple prop. Like those manikins in the mall, that
stand there for 10 minutes not moving, then they repose.

http://en.wikipedia.org/wiki/Suspension_of_disbelief

Just when they accept they are looking at a prop, but accept it as a
turtle anyway, you reward and awe them for their disbelief.

The larger subject you are asking about is animatronics.
http://en.wikipedia.org/wiki/Animatronics
You might want to google on the subject with turtle and see many
results. Looks like 60,000.

Looks like you might even be able to rent one already made:
http://www.lifeformations.com/galleries/animals/index.htm#

--
Randy M. Dumse
www.newmicros.com
Caution: Objects in mirror are more confused than they appear.

I used to work for Sight & Sound Theatres, which does very large scale
biblical dramas.  They use a lot of animatronic animals.

There are certainly times when a real animal on stage looks fake
because it is not moving.  The real animals just get used to their
jobs, and don't even bother to look around at what is going on around
them.

Stages can be a challenge for R/C because there are lot of radio mikes
and other RF sources.  An alternative is to use a purely mechanical
motion, directly moved by an actor who is handling the turtle (perhaps
by inserting a finger in a hole on the upstage side or underside of
the turtle).  It is reasonable for a turtle to simply stay inside its
shell when it is placed on the floor (of course the ability to do this
may depend on the play).

Sight & Sound Theatre is known for "Grand Spectacle," so they have an
additional reason for animatronics.  But, for most stages, I suspect
it is best to avoid animatronics entirely (even if it is more fun for
the technical staff).

If you want to do the animatronic turtle easily, I would suggest
forgetting about the legs.  Just buy any R/C car that has a steering
servo.  Remove the guts of the car (the wheels and drive motors are
not needed).    The stering servo should have an arm on it. If the
head/neck of the turtle is a separate piece from the turtle, you can
mount the servo inside and connect the arm of the servo to the end of
the neck.  Simply moving the steering on the transmitter can then move
the head in and out of the shell.

Joe Dunfee