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Matlab code used for vehicle dynamics

  1. Jan 31, 2012 #1
    Please help me recognize what is wrong with this professor supplied code...

    clear all
    options=odeset('events', @events_passing)
    [t,z]=ode45(@passing,[0,10],[0,50*88/60],options)
    plot(t,z)

    function [value,isterminal,direction]=events_passing(t,z)
    value=z(2)-88;
    isterminal=1;
    direction=0;
    end


    %Gillespie Data Page32
    function torque=engine_gillespie(omega)
    torque_coeff =[-1.5752e-006 7.9768e-004 1.8454e-001 9.9834e+001];
    torque=polyval(torque_coeff,omega);

    function f=passing(t,z)
    f=zeros(2,1);
    x=z(1);
    v=z(2);
    g=32.2;
    M=2500/g;
    I_e=0.8/12;
    I_t=0.5/12;
    I_d=1.2/12;
    I_w=11/12;
    N_t=1.36;
    N_f=2.92;
    N_tf=N_t*N_f;
    Re=12.59/12;
    rho=0.00236;
    c_d=0.32;
    A=20;
    f0=0.015;


    M_r=(I_e+I_t)*N_tf^2/Re^2+I_d*N_f^2/Re^2+4*I_w/Re^2;
    M_equivalent=M+M_r;

    dvdt=(engine_gillespie(v*N_tf/Re)*N_tf/Re-f0*M*g-0.5*rho*A*c_d*v^2-M*g*sin(atan(.02)))/M_equivalent;
    f(1)=v;
    f(2)=dvdt;
     
  2. jcsd
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