constructing Parallel curves offset

Can anyoane tell be if it is possible to buil in Matlab an offset for a curve ? If yes, which is the approche ? This is what I got until now. I think the offset is changing because of the concavity.

Thank you very much in advance.

Answer 1

[Star Strider]

See if this does what you want:

x = [10 30 10 25];                              % Create Data: Original
y = 10 : 20 : 70;                               % Create Data: Original
xof1 = x - 2;                                   % Create Data: Negative Offset
xof2 = x + 2;                                   % Create Data: Positive Offset

figure(1)
plot(x, y)
hold on
plot(xof1, y)
plot(xof2, y)
hold off
axis([-20  60    10  70])

[Andries Paula]

Hey,

Thank you very much for your response.

yes, but if I am trying with this coordinates the offsets are not parallel lines anymore. I think I need to use formulas for gradient and radius of curvature.

 x=1:100;
 y=sin(x);
 xof1 = x - 2;                                   
 xof2 = x + 2;

[Star Strider]

My pleasure.

The curves are now offset in the y-direction.

What do you want to do, and how do you want to calculate ‘Inner Parallel’ and ‘Outer Parallel’?

What do they represent?

Is it a regression curve with confidence intervals?

[Andries Paula]

Hey,

I have coordinates ( X and Y ) for a road, and I need to draw right and left offsets to the road lines. I wrote a program using the gradient, normal vector, cancavity and the radius of curviture, but the result it is not correct.

[Star Strider]

Road design is not an area of my expertise. I have no idea what the constraints and other problems are.

You may need to use more points to approximate your road centre-line and the parallels.