A
servo controlled
system is disclosed for providing simulated feel equivalent to that of traditional mechanical hand controllers using servomotors. Position and
force sensor signals are processed and used in a
feedback loop that controls the motor mechanically connected to the stick. The overall
feedback loop is comprised of a low-level motor
feedback loop, and high-level force feel loop. The two loops have associated performance parameters that can be specified independently. The high-level feel force loop is comprised of a static and dynamic performance components. Static and dynamic performance components can be specified independently. The
system allows variable and / or additional force cues to be specified externally to the
system and felt by the operator. The system also allows external
signal to
backdrive die stick to follow a specified motion. The control framework permits the electronic
coupling of the motion and applied forces of
pilot and co-pilots in a dual arrangement while retaining the above-mentioned features. It also allows asymmetric force feel gradients to be implemented for each stick, or for a stick relative to a second one. A zero breakout or
detent can be provided at the stick null displacement. For cross-coupled sticks, the
detent can be shared as in a mechanically cross-coupled system, implemented independently on each slick, or any combination of these two. The control framework also provides the
simulation of mechanical compliance in the cross-
coupling of the two sticks in case of a jam or of force fight between the pilots, and automatic de-
coupling of the sticks.