View Single Post
Old Jan 06, 2013, 04:22 PM
airpower is offline
Find More Posts by airpower
Have fun
airpower's Avatar
United States, CA, Mission Viejo
Joined May 2007
6,319 Posts
Nemo, I am confused. I thought you were saying that as3x ships have to be on gear and level to initialize proper, which is incorrect since it only uses gyros and doesn't use accelerometers, I guess my post was too vague to get the the fact that as3x only uses gyros, not accels. Sorry I was vague.

Re-examining your second post perhaps you misunderstand what as3x does. When you take your fingers off the sticks it will NOT go back to the attitude it initialized or what is level, it only counter reacts to movement as they happen, the term is rate gyro, it only reacts with opposite control as the rotation occurs to reduce uncommanded deviations.
Helis use heading hold gyros, also they do not return the ship to the attitude where it was initialized, it stays EXACTLY where you LAST put, the difference is that a heading hold will return an uncommanded position back to the last place you commanded it, difficult concept sorry, here's an example.
Constant is no input.
A plane with no gyros: gust causes a yaw left, aerodynamic forces move it as they wish.

Plane with rate gyro: gust cause yaw left, gyros counter and reduce total yaw from gust by 50%.

Plane with heading hold: gust causes yaw left, gyro initially counters and reduces yaw by 50%, after gust ends gyro yaw right back to the last position. Now,this is complicated, it will not bring the plane back to the last commanded position, not initialization position. The last commanded position depends on your inputs. For explanations sake lets say the HH gyro is active even when throttle is down on heli. The last commanded position starts where it initialized, and depending and depending on your inputs it will change, depending how much you move elevator, rudder, and aileron.
People much better on other websites probably explain this much better than I do, sorry if I over explained it, it's better than under explaining.
Really sorry to change the subject a bit on your important inquiry, but it's a valuable thing to learn about when learning how to deal with gyros.
Also as a rule of thumb, rate gyros are usually used and planes, heading hold on helis.
airpower is offline Find More Posts by airpower
Reply With Quote