Plot a graph of a force in relation to two independent angles

I want to plot a graph of the calculated forces in relation to the two independent angles alpha (angle upper arm) and zeta (angle bottom arm).

The code below calculates F5,F6 anf Fp2 per angle of zeta for all possible angles of alpha.

I was able to make 2d plots, but I would like a plot that has alpha zeta and F5 on it. The problem is that per zeta there are 90 alpha's so I don't know if it's possible.

Thanks in advance!!

%% Middenstuk
pis=3
alpha=[1:1:90]
x=20
kak=6
[hoeksup]=zeros(1,90)
for i=1:90
hoeksup(i)=asind((kak*sind(135-alpha(i)))/(sqrt((x^2)+(kak^2)-(2*x*kak*cosd(135-alpha(i))))))
end 
Z=(kak*cosd(45))/2
Y=Z*2
beta=alpha-hoeksup
aap=90-alpha
zeta=[1:1:90]
[hoeksup2]=zeros(1,90)
e_array = {};

for i=1:90
hoeksup2(i)=asind((kak*sind(135-zeta(i)))/(sqrt((x^2)+(kak^2)-(2*x*kak*cosd(135-zeta(i))))))
end 
Z=(kak*cosd(45))/2
Y=Z*2
gamma=zeta-hoeksup2
for i=1:90
syms F5 F6 Fp2
eqn6=(d.*cosd(alpha))-([q.Fp].*cosd(beta))+(p.*cosd(alpha))+(F5*cosd(zeta(i)))-(Fp2*cosd(gamma(i)))+(F6*cosd(zeta(i)))==0
eqn7=0==-(d.*sind(alpha))+([q.Fp].*sind(beta))-p.*sind(alpha)+F5.*sind(zeta(i))-Fp2.*sind(gamma(i))+F6.*sind(zeta(i))
eqn8=0==-d.*cosd(alpha)*(Y+pis)+d.*sind(alpha)*(Y)+[q.Fp].*cosd(beta)*(2*Y+pis)-p.*cosd(alpha)*(2*Y+pis)-F5.*sind(zeta(i))*Y-F5.*cosd(zeta(i))*Y
for K = 1 : length(eqn6)
  e(K) = (vpasolve([eqn6(K),eqn7(K),eqn8(K)], [F5,F6,Fp2]))
end
e_array{i} = e; % <--- store them for later use
figure(4);
plot(zeta,[e.F5],'r')
hold on 
plot(zeta,[e.F6],'b')
hold on
plot(zeta,[e.Fp2],'g')
hold on
title('Krachtverloop in middenstuk') 
xlabel('Hoek onderarm [°]')
ylabel('Krachten op arm [N]')
legend('F5 = Kracht in scharnier 5','F6 = krachten in scharnier 6','Fp2 = krachten in piston 2')
end

[darova]

• The code below calculates F5,F6 anf Fp2 per angle of zeta for all possible angles of alpha.
• I was able to make 2d plots, but I would like a plot that has alpha zeta and F5 on it. The problem is that per zeta there are 90 alpha's so I don't know if it's possible.

You didn't show any of those. Where a those values?

YOu didn't attach data/variables: kak,x,alpha,beta

[Xavier Croes]

They were in the earlier part of my coding, I've put them in now, sorry.

[Xavier Croes]

These are the values of the forces

[darova]

[Xavier Croes]

Once again sorry! This is what comes before it (claculations for d and q etc.)

Thanks for your time!!!

clear all 
close all 

%% Bovenstuk

F=800 %[N] 
hoekF=80
alpha=[1:1:90]
x=20
kak=6
[hoeksup]=zeros(1,90)
for i=1:90
hoeksup(i)=asind((kak*sind(135-alpha(i)))/(sqrt((x^2)+(kak^2)-(2*x*kak*cosd(135-alpha(i))))))
end 
Z=(kak*cosd(45))/2
Y=Z*2
beta=alpha-hoeksup
aap=90-alpha


syms F1 F2 Fp
eqn1=(F*cosd(hoekF))+(Fp.*cosd(beta))==(F1.*cosd(alpha))+(F2.*cosd(alpha))
eqn2=(F*sind(hoekF))+(Fp.*sind(beta))==(F1.*sind(alpha))+(F2.*sind(alpha))
eqn3=(F*sind(hoekF))*(Z)+(Fp.*cosd(beta))*(kak*cosd(45))+(Fp.*sind(beta))*(kak*cosd(45))==(F1.*cosd(alpha))*(kak*cosd(45))+(F1.*sind(alpha))*(kak*cosd(45))

for K = 1 : length(eqn1)
  q(K) = (vpasolve([eqn1(K),eqn2(K),eqn3(K)], [F1,F2,Fp]))
end

figure(1);
plot(alpha,hoekF,[q.F1],'r')
grid on
hold on 
% plot(alpha,[q.F2],'g')
% hold on
% plot(alpha,[q.Fp],'b')

%% arm links in de bovenste parallellogram 

syms F3 
eqn4=(F3)==([q.F1])
for K = 1 : length(eqn4)
  d(K) = (vpasolve(eqn4(K),F3))
end

figure(2);
plot(alpha,[d],'r')
grid on
hold on 
title('Krachtverloop in arm 1') 
xlabel('Hoek bovenarm [°]')
ylabel('Krachten op arm [N]')
legend('F3 = Kracht in scharnierpunt 3')
%% arm rechts in de bovenste parallellogram 

syms F4 
eqn5=(F4)==([q.F2])
for K = 1 : length(eqn5)
  p(K) = (vpasolve(eqn5(K),F4))
end

figure(3);
plot(alpha,[p],'r')
grid on
hold on 
title('Krachtverloop in arm 2') 
xlabel('Hoek bovenarm [°]')
ylabel('Krachten op arm [N]')
legend('F4 = Kracht in scharnierpunt 4')

[darova]

If alpha has 90 values for each zeta

Shouldn't F5 F6 Fp2 be 90x90 matrices or something?

[Xavier Croes]

The for loop always puts one zeta in the equations and then calculates these eqations voor alpha going from 0 to 90. I then safe these values in an array (e_array{i} = e;) and do it again for the next zeta (zeta(2) for instance))

[darova]

What about surf?

[Xavier Croes]

Surf(X,Y,Z) gave me an array that the input in the place of Z was not a matrix.

Error using surf (line 71)

Z must be a matrix, not a scalar or vector.

And when I tried to make it a matrix it's said that it was unable to make the plot because of the 'sym' type.

mat=struct2array([e.F5])
surf(alpha,zeta(i),mat)

Undefined function 'struct2cell' for input arguments of type 'sym'.

Error in struct2array (line 10)

c = struct2cell(s);

Error in 22032020 (line 94)

mat=struct2array([e.F5])

[darova]

IS mat a matrix? 90x90 or something?

surf(alpha,zeta(i),mat)

[Xavier Croes]

I get following error when I try to make mat

Undefined function 'struct2cell' for input arguments of type 'sym'.

Error in struct2array (line 10)

c = struct2cell(s);

Error in 22032020 (line 94)

mat=struct2array([e.F5])