Clear Filters
Clear Filters

How to make a curve smooth in spline block

6 views (last 30 days)
dk2507
dk2507 on 28 Feb 2017
Commented: Massimo Zanetti on 28 Feb 2017
Hi, i need to make a cam model in simulink so i use a spline block to model the curve.Here is my code:
clear
clc
s=0:0.005:1;i=0;
for t1=0:0.005:0.125;
i=i+1;
s(i)=(pi*t1-0.25*sin(4*pi*t1))/(pi+4);
end
for t2=0.130:0.005:0.875;
i=i+1;
s(i)=(2+pi*t2-(9/4)*sin((pi+4*pi*t2)/3))/(pi+4);
end
for t3=0.880:0.005:1
i=i+1;
s(i)=(4+pi*t3-0.25*sin(4*pi*t3))/(pi+4);
end
T=0:0.005:1;
% plot(T,s);
r=1:1:21;n=0;
for m=1:5:201
n=n+1;
r(n)=(232^2+264.2^2-2*232*264.2*cos(deg2rad(20.69+18.5*s(m))))^(1/2);
end
th=60:(110/40):170;
x1=r.*cos(deg2rad(th));
y1=r.*sin(deg2rad(th));
% figure(2);
th2=170:0.5:190;
x2=169.*cos(deg2rad(th2));
y2=169.*sin(deg2rad(th2));
th3=300:(-110/40):190;
x3=r.*cos(deg2rad(th3));
y3=r.*sin(deg2rad(th3));
x3=fliplr(x3);
y3=fliplr(y3);
th4=-60:5:60;
x4=94.55.*cos(deg2rad(th4));
y4=94.55.*sin(deg2rad(th4));
x=[x1,x2,x3,x4];
x=x';
y=[y1,y2,y3,y4];
y=y';
% subplot(5,3,1);
% plot(x,y);
% axis([-150,150,-150,150]);
CAM=[x,y];
But the curve is not smooth,please tell me what is the problem.

Answers (1)

Massimo Zanetti
Massimo Zanetti on 28 Feb 2017
If you want to approximate a set of points by a smooth curve you need a smoothing spline, not just a spline. Moreover, in your case you need the smoothing spline to be a closed curve, therefore with periodic conditions.
I have done a function to do exactly that, check it out:
  4 Comments
dk2507
dk2507 on 28 Feb 2017
I have fixed the problem .Though there are now new problems coming out,still,thank you very much ,helps a lot.
Massimo Zanetti
Massimo Zanetti on 28 Feb 2017
Glad to know you have fixed. If this answer helped you, please accept it.

Sign in to comment.

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!