Society of Robots - Robot Forum

Mechanics and Construction => Mechanics and Construction => Topic started by: Arislan on October 18, 2006, 04:13:58 PM

Title: Why air?
Post by: Arislan on October 18, 2006, 04:13:58 PM

I have seen a lot of android projects using pneumatic muscles. Why not hydraulics? I would have thought that hydraulic motors were a lot more powerful. In fact, most robots in sci-fi have hydraulic pistons, not a bunch of air hoses...

Title: Re: Why air?
Post by: Gopher on October 18, 2006, 04:23:30 PM

Two very good reasons come to mind immediately.

1) air is much, much lighter than any fluid, and the less weight the bot's lugging around the better
2) moving air around consumes far less energy than moving fluids around, and the less power the bot consumes the better.

Title: Re: Why air?
Post by: Arislan on October 18, 2006, 04:48:03 PM

Do you know what type of actuator is used in Asimo?

http://asimo.honda.com/movie/wm_stream/intelligence_tech_300.wmv

Title: Re: Why air?
Post by: Admin on October 19, 2006, 09:36:18 AM

3) hydraulics are messy when they leak
4) hydraulics are more expensive

Asimo uses special servo motors custom built by Honda that has much higher strength than your typical motor . . . these motors are kept top secret and not for sale . . . sigh  :-\

Title: Re: Why air?
Post by: Cognaut on November 27, 2006, 09:26:01 PM

A gas is compressible, so it will have a more elastic behavior than a liquid.