Fly-by-wire and Actuation

Question 1

The main advantages of the Fly-By-Wire flight control are summarised as follows:

Answer 1

 Elimination of mechanical control runs.
 Consistent handling over a wide flight envelope.
 Automatic stabilisation.
 Carefree manoeuvring.
 Automatic integration of additional controls.
 Ability to exploit aerodynamically unstable aircraft.

Question 2

The armature current and the torque are related by:

Answer 2

Tm = kI

Question 3

Copper loss of a motor is given by

Answer 3

Pc = R*I^2 in watts

Question 4

when copper loss of a motor is considered the efficiency is given by

Answer 4

(Tm +Omegam)/(TmOmegam + RI^2) = 1/[1 + R*Tm/k^2 *Omegam]

Question 5

when both copper and friction loss is considered, motor loss is given by

Answer 5

=(TmOmegam - TfOmegam)/[(TmOmegam - TfOmegam) + R*I^2]

= (1 - Tf/Tm)/[(1 - Tf/Tm) + [R*Tm/k^2 *Omegam)]