Question

In a NED navigation frame, which is assumed to be flat-Earth and inertial, write a MATLAB program to:

(a) Plot a circular trajectory P = [ px py pz] centered on the zn -axis at an altitude of 2000 meters with a radius of 1000 meters, starting from py= 1000 meters due north. Put a marker at the start point and indicate the direction of flight.

(b) Plot the same circular trajectory as in (a) but with the center at 1000 meters to the north, and in the opposite direction.

Answer 1

MATLAB code is given below in bold letters.

clc;
close all;
clear all;

% Question a
theta = (0:0.1:360)*pi/180;
radius = 1000*ones(size(theta));

figure;
plot(radius.*cos(theta),radius.*sin(theta),'linewidth',2);grid on;
axis('equal');xlabel('y axis');ylabel('x axis -> towards north');
xlim([-1.2e3 1.2e3]);
ylim([-1.2e3 1.2e3]);
hold on;plot(1000,0,'or','linewidth',5);

100마 500 0 500 . . 1000 -1000 500 500 1000 y axis

% Question b
theta = (0:0.1:360)*pi/180;
radius = 1000*ones(size(theta));

figure;
plot(radius.*cos(theta),radius.*sin(theta)+1000,'linewidth',2);grid on;
axis('equal');xlabel('y axis');ylabel('x axis -> towards north');
xlim([-1.2e3 1.2e3]);
ylim([-0.2e3 2.2e3]);
hold on;plot(1000,1000,'or','linewidth',5);

2000. 1500 1000 500 . . 0 1000 500 500 1000 y axis