Consider the satellite control system of Fig. P5.3-14. The units of the attitude angle (t) is

Consider the satellite control system of Fig. P5.3-14. The units of the attitude angle θ(t) is degrees, and the range is 0 to 360° . The sensor gain is H_k = 0.02 .

(a) Suppose that the input ranges for available A/D s are 0 to 5 V, 0 to 10 V, 0 to 20 V, ±5 V ,±10 V , and ±20 V . Which range should be chosen? Why?

(b) The input signalr (t) is a voltage. Find the required value of r(t) to command the satellite attitude angle
θ(t) to be 70° .

(c) Repeat parts (a) and (b) if the range of θ(t) is ±180° .

(d) Let Gp (s) = 1 / (Js₂), the satellite transfer function. Find the system transfer function as a function of the transfer functions D(z), K , and so on.

(e) Evaluate the system transfer function for D(z) = 1 , T = 1 s, K = 2 , and J = 0.1 .

Transcribed Image Text:

R(s) + r(t) A/D Digital Controller D(z) DIA M(s) Sensor H Amplifier and thrusters K T(s) Torque Satellite 0(s) 8(t)