but i got a simple doubt..
just to keep the helicopter stable in air i should use accelerometers or gyrocopes??
if accelerometer.. then what about the effects from the external forces like the disturbances we give etc..
if gyro then it gives angle turned in seconds..
should i convert it to angle using real time numerical integration or some other ways to deal with the angle tilt measurement??
To do it properly you would actually use both, a fully complemented IMU (Inertial Measurement Unit). However, 3 gyros, one for each axis will get you pretty darn stable.
With either you will need some sort of feedback loop and digital filtering, PID for instance.
No reason to doubt any of this, and no reason to try to re-invent what is already been done very well.
Just look at the Mikrocopter. It uses 3 gyros for, roll, pitch, yaw, and a pressure sensor for altitude, and it is extremely stable.
Just look at the 6 rotor version of the Mikrocopter here
http://vimeo.com/6194911