High torque metal gear micro servos..why not?

[miller]

I'm pretty new to the crawler scene as in this year I got my ax-10. Why have servos been the same size for over a decade? The last rc I had was when I was in highschool.

Why aren't there any high torque metal gear micro servos? Anyone have any leads on any being produced? It would be so nice to be able to mount one tucked away on the side of the axle near the tire instead of a brick in the center. I'm sure the scalers would love em...robot makers would love em, flying things would use them...why aren't there any?

 

[mysharona]

crawlers need around 200 oz/in of torque minimum. currently I belive Integy has the strongest micro servo with 69oz/in. not nearly enough for a crawler.

there are plenty of small servos out there, but the standard size is just that, the standard.

 

[miller]

I know, that's why I'm asking why there aren't any. Ten-twenty years and we have all these fancy electronics, speed controls, tiny brushless motors yet we're still steering with bricks?

 

[breitenbach14]

i dont know about that but on my clod i have the suspension less chassis and moabs xls and i stripped my mettal gear servo and i think it was the hitec hs-5645mg

 

[HndsWthtShdws]

You can only make a 6v motor that fits inside a micro servo case so powerful. Maybe if some company felt that enough crawlers were running 3s lipo to make a single purpose 12v micro servo we would see some. The market just isn't there.

 

[miller]

Crawlers are hardly the only people that use servos. Anyone that builds robots, airplanes...anything that moves could benefit from a small high torque servo.

 

[DKNguyen]

I know, that's why I'm asking why there aren't any. Ten-twenty years and we have all these fancy electronics, speed controls, tiny brushless motors yet we're still steering with bricks?

THere are metal gear micro-sized servos. Just look at Hitech.

Now high torque micro-servos? THat's simple to answer-It's just the limit of technology. Motor technology has more or less remained the same. So same sized motor = same torque = same torque density = no stronger smaller servos. Unless new better materials for magnets can be found or something completely new actuator altogether (both of which are probably sky high expensive and would keep them out of the RC market anyways) things are going to stay as they are.

Mechanical things tend to advance much more slowly than electronics, and the hunt for new materials an even harder and longer one.

If you are going to compare brushless motors as an advance in motor technology, it's not really. Heck, brushless motors are even easier to make than brushed motors. Brushless motors have been around as long as AC synchronous motors have- they are, in fact, the same thing. The onyl difference is an BLDC has electronics convert DC into AC for it to run off of rather than a straight AC source. The increase in brushless motors lately has been due to the decreased cost of the electronics required to run them. So, in fact, all the advances you just listed are advances in electronics and not motors. And, unfortunately, transistors can't make a motor smaller and stronger.

It's like comparing cars to computers. What makes a car at it's core is pretty much the same after all these years despite all the things tacked on. (WHere all the freakin' hover cars?!)