So you see proportional changes at trackbars (both joystick's (upper) and drone's (lower)) but ardrone reacts too fast? If so "flight settings" can be changed to reduce maximum tilt, etc angles.all axis are proportional in the joystick adjustment window, but the drone pitch\roll reaction isn't
It works the following way: joystick movements are normalized to -1 1, ardrone receive commands as a fraction of 1, e.g 0.3 means 0.3 of maximum tilt angle. You also may try manually change sensitivity by editing AxisMax, AxisMin, and AxisZero values in the parameter file. Sure I can add nonlinearity setting, but I dont have any experience with it, do you have any example what nonlinearity is needed (is a+bx+cx^2 with adjustable a,b,c good enough?).