wrote:

Thats what is done on RC Heli's, the rate gyro directly sums into the
normal command. The only control you have is the gain on the gyro and
I'd guess you'd have to adjust this to particular aircraft and
preference of the pilot.

I assume the gyro(s) would be pretty near the center of motion along
with the pilot, but why is this a requirement? Doesn't any ridged part
of the aircraft experience the same yaw,pitch,roll accelerations? One
possible implimentation could be a gryo co-located with the actuator
(servo) that controls that axis.

Take a 12" ruler rotate it around 4" mark. Imagine you have rate gyros
at the 4" and 11" marks. The one at the 4" mark senses only rotational
rate, the one at the 11" mark senses rotational rate plus a G force. If
you read the specs on pizeo rate gyros they are G limited. You can buy
them with G limits in excess of 50G but they can be pricy. Exceding the
G limit on a pizeo gyro won't neccesarily kill it, but you will get an
error which defeats the purpose.

None of the aircaft I worked on had pizeo gyros, but the theory still
holds. The power steering rate gyros on the F-4E are mounted in the
wings near the roots. It's not my idea of fun to change them either.

Sometimes design considerations preclude mounting near the axis, but if
you can do it it will reduce induced errors.

I think this would replace manual trim because if you could do the
stability control, you sure as heck could make it move back and forth
in response to a 3 position toggle switch.

To be really cool install a coolie hat switch.

If it breaks you fly without trim till you land. I think there is some
rule that the aircraft must be controllable with any trim to it's full
limit.

I used to fly R/C way back in the dark ages. Unless servos have
radically changed you shouldn't have problems unless they don't provide
enough force to the tabs near the limits of the servo's travel.

Dan, U.S. Air Force, retired