"Tim Wescott" wrote in message
...
On 06/23/2011 12:48 PM, Cydrome Leader wrote:
wrote:
I've been interested in small brushless motors for some time and it
seems like the ones made for RC use are plentiful and cheap. Bujt I'm
having a hard time getting my questions answered about these things.
My uses will not be in some type of RC toy, but "toys" that I want to
make for myself. I know I will need to get an ESC to drive the motor.

I'm not sure what you're making, but the power to weight of those
brushless motors is quite impressive.

There's a catch though, if you're not using them to just run a fan, which
is all they're good for.

they lack position sensors, so you can't just spin them back and forth
like a regular motor unless you have some sort of really awesome motor
controller.

They seem to now have brushless RC car motors and controllers. I'm not
sure how those work though.

I believe the brushless car motors have hall sensors for commutation, the
same as an industrial servo brushless would.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html


The rc car's "electronic speed control" (ESC) support both sensor and
sensor less brushless motors. You can program into the handheld transmitter
throttle and braking endpoints and curves, linier or otherwise. The speed
controlls can deliver lots of power. My Emaxx 1/10 scale rc truck will pull
300 amps acceleration and 180 amps on braking at 16.8 volts. With motors
pulling lots of power things can get hot in a hurry.
Spektrum transmitter's and receivers are what I prefer. The "2.4Ghz" units
eliminate interference and channel crystal changing when near other units.
They will automatically switch up to 80 channels/units in the same location.
You program failsafe throttle and other servo positions in case of signal
loss. Check your local rc racing club. They usually have a web site with
help and buy/sell forums