What kind of Pump do I need for Hydraulic movement in an animatronic puppet.?

I want to build a Hydraulic-based animated figure. Heck, I want to just build a small frame with a single moving piece and actuate it with Hydraulics. The trouble is, information on Hydraulics for hobby robotics/Animatronics on the web is pretty thin. I've found quite a bit of Servo related stuff, a little bit of Pneumatic stuff, but so far I haven't had luck finding a good tutorial on automated Hydraulic animation. Truthfully, I need information on the whole picture, but I understand the basics of getting a cylinder to move and how to set that up. I know how to do it with Pnuematics. Air is not quite power/accurate enough for what I want to do. I want Hydraulics. Ideas?

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aggrav8d6 years ago
Old thread revival!

solenoids run from an arduino would work great for opening & closing valves. You'll often see them in drink-mixing robots. At hobby scales you can probably get away with thick-walled plastic tubing and not have to get reinforced plumbing. Remember that the system is pressurized all the time, so your connections are going to be the big trouble spots. The strength of your pump will determine the amount of force your actuators can apply. You'll also want a filter to keep your lines clean and a reservoir.

Example here: http://www.youtube.com/watch?v=1tCsyb2G8No

More info here: http://en.wikipedia.org/wiki/Hydraulic_machinery

Oh and the hydraulics being used in the video are from Modell Technik Hausl. They only make hydraulics for model planes and don't (atm) make anything for robotics fans like you and I.
aarone (author)  aggrav8d6 years ago
Wow, Hurray for Old Thread Revival!

This is EXACTLY the kind of answer I was looking for. Thanks for sharing the link to the walking table. Given a little cash, I'm definitely going to look into building something using this kind of technique.

Thank you so much!

that is wrong

aarone (author)  Mangle1011 year ago

Hi Mangle101,

How is this wrong? Is there a better solution that you can recommend?

Mangle1011 year ago

hi

bleep

How about this?
Connect a syringe to a fairly rigid tube and the rigid tube to a thin-walled tube or a balloon. When the system is filled with water (and no air), moving the plunger should cause the tube to straighten or the balloon to inflate. Unlike air, water is almost incompressible, so when you push one end, the whole mass will move. (Water can 'tear' if pulled hard enough, but that shouldn't matter here.)

I can imagine strapping a bundle of syringes to a heavy block and adding finger-loops to the plungers to make it easier to control more actuators with fewer fingers.
aarone (author)  NobodyInParticular8 years ago
The concept is right, but I'm looking for a way to automate it. I want to control it with a Microcontroller (specifically an Arduino), I need a pump and/or an electric valve to move hydraulic fluid, rather than man-powered.
I would stick with a low-tech solution if at all possible. More complicated systems just mean more things that can break.

That said, you might look into using a servo with a worm gear to drive the plunger of the syringe.
Great thought nip... 2 syringes connected with tubing would work also - if you need linear actuation. A screw actuator to move the one cylinder would work - just make sure your hose and fittings are rated for the pressure of this that or the other.
No problem. Be sure to post an Instructable when you do get it working.