function du=mydiff(tau,u)tau= 1:20;for tau=1:20 u(tau)=1;endb=4.5; %backlash,2b=9 micro metre
Z1=62; %no. of teeth in Gear
Z2=42; %no. of teeth in Pinion
T1=7640; %torque of Gear in N-mm
N1=5000; %Speed of Gear in rpm
M1=11.815; % mass of gear in kg
M2=5.357; %mass of pinion in kg
I1=37257; %inertia of Gear in kg-mm2
I2=82103; %inertia of pinion in kg-mm2
me=2.279; %mass equivalent in kg
km=2.3426e7; %average stiffness in N/m
Fm=105; %total Normal force in N
omega0=sqrt(km/me); % frequency of gear pairin rad/sec
omegae=(2*pi*Z1*N1)/60; %natural frequency in rad/sec
ohm=omegae/omega0; % frequency ratio
F0=0.4482; %Dimensionless load=(Fm/me*l*omega0^2)
zeta=0.06; %damping ratio
t=[];%f(u(tau)) Dimensionless nonlinear gap function
tau=omega0*t; %Dimensionless time
l=1e-6; %characteristic length
q(t)=l*u(tau);thetaj=0;kj=[23.5396 3.5448 0.8489 0.5454 .0302 0.5012]*10^6;kbn=kj/km;ej=[20 3.45 0.26 .45]*10^-6;ejb=ej/l;for tau=1:20 if(u(tau)>b/l) f(u(tau))=u(tau)-b/l; end if(u(tau)> -b/l && u(tau)<b/l) f(u(tau))=0; end if(u(tau)<-b/l) f(u(tau))=u(tau)+b/l; endendfor n= 1 :5 sum1=kbn*cos(n*ohm*tau)*f(u(tau));endsum1=sum1+1;for j=1:5 sum2=ejb*j*j*cos((j*ohm*tau)+thetaj);enddu(1) = u(2); du(2) = F0+(ohm*ohm*sum2)-sum1-(2*zeta*u(2));du = [du(1); du(2)];[tau,u] = ode15s('mydiff', [0 25], [1 1]); plot(tau,u(:,1))
whats wrong with this program?
Best Answer