Solve an differential equations system

Hi all I have been trying to reproduce some waveforms, but I cant, I don't know if I need some other complex methods, I had tried with some ODE's as well as with the function dsolve, but I couldn't get it.

I've thinking that may be only I need some adjust in my code or another thing...

Really, I hope you can help me :(

This is my code:

clear all
clc
close all

%constants
a=(5400*10^-3);
b=30;
z=0.008;
%z=-0.023;
%z=0.034;

c=0.00017;
d=0.001;
e=0.01;
h=0.1;

q=0.024;
r=0.088;
s=0.046;

f=@(t,x)[(-5400*10^-3)*((0.00017*x(1)^3+0.001*x(1)^2+0.01*x(1)+0.1)-x(2)-0.008);30*((0.00017*x(1)^3+0.001*x(1)^2+0.01*x(1)+0.1)-(0.024*exp(0.088*x(1))+0.046)-x(2))];

% tspan=[-0.04 0.04];
x0=[0 0];

[X,Y]=ode45(f,(tspan),[a*z,0]);

figure
plot(Y)
figure
plot(Y(:,1),Y(:,2),'-')

And I need get the wave forms of the images, where fig 2 is the system solution and the Fig. 3 is a cicle of the biffurcation, I hope you can help me what I can do with ode45? I need an adjust? Or try with other functions?. I have attempted to solve with ode45, ode15, rungekutta, euler, etc.

Thank's.

[Jorge Herrera]

I obtained these waves, I don't know maybe only I need some adjusts

Answer 1

[Jorge Herrera]

Good news, I kept working with my code and the paper, after an exhaustive analysis I noticed that some parameters were incorrect. I get the waveforms.