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The complete "rotation" of the caliper around the polygon detects all antipodal pairs; the set of all pairs, viewed as a graph, forms a thrackle. The method of rotating calipers can be interpreted as the projective dual of a sweep line algorithm in which the sweep is across slopes of lines rather than across x - or y-coordinates of points.
Rotation applies to tricycle gear aircraft rather than those with conventional gear (tailwheel aircraft). The on-ground angle of attack of the wing has to be established during the design phase. The main and nose-gear leg lengths are chosen to give a negative angle of attack relative to the ground.
The controls (stick and rudder) for rotary wing aircraft (helicopter or autogyro) accomplish the same motions about the three axes of rotation, but manipulate the rotating flight controls (main rotor disk and tail rotor disk) in a completely different manner. Flight control surfaces are operated by aircraft flight control systems.
Helicopter rotors are designed to operate at a specific rotational speed. The throttle controls the power of the engine, which is connected to the rotor by a transmission. The throttle setting must maintain enough engine power to keep the rotor speed within the limits where the rotor produces enough lift for flight.
A servomotor is a packaged of several components: a motor (usually electric, although fluid power motors may also be used), a gear train to reduce the many rotations of the motor to a higher torque rotation, a position encoder that identifies the position of the output shaft and an inbuilt control system. The input control signal to the servo ...
An aircraft is streamlined from nose to tail to reduce drag making it advantageous to keep the sideslip angle near zero, though an aircraft may be deliberately "sideslipped" to increase drag and descent rate during landing, to keep aircraft heading same as runway heading during cross-wind landings and during flight with asymmetric power.
The simplest form of the rotor constrains the disk to a plane orthogonal to the axis of rotation. This limits the rotor's response to lateral vibration only. If the disk is perfectly balanced (i.e., its geometric center and center of mass are coincident), then the rotor is analogous to a single-degree-of-freedom undamped oscillator under free ...
The amount of phase lag depends on the distance of the flapping hinge from the rotor hub. If the hinges are only slightly offset, phase lag will be 80-90 degrees, however a semi-rigid rotorhead will typically have phase lag of 75-80 degrees. [1] Phase lag is not caused by gyroscopic precession, which always has a lag of 90 degrees. [2]