function out = stewartplatform(theta)<br>
% Calculates theta<br>
p1 = sqrt(5);<br>
p2 = sqrt(5);<br>
p3 = sqrt(5);<br>
L1 = 2;<br>
L2 = sqrt(2);<br>
L3 = sqrt(2);<br>
gamma = pi/2;<br>
x1 = 4;<br>
x2 = 0;<br>
y2 = 4;<br>
<br>
A2 = L3 * cos(theta) - x1;<br>
B2 = L3 * sin(theta);<br>
A3 = L2 * cos(theta + gamma) - x2;<br>
B3 = L2 * sin(theta + gamma) - y2;<br>
<br>
N1 = B3 * (p2^2 - p1^2 - A2^2 - B2^2) - B2 * (p3^2 - p1^2 - A3^2 - 
B3^2);<br>
N2 = -A3 * (p2^2 - p1^2 - A2^2 - B2^2) + A2 * (p3^2 - p1^2 - A3^2 - B3^2);<br>
D = 2 * (A2 * B3 - B2 * A3);<br>
out = N1^2 + N2^2 - p1^2 * D^2;<br>