OB=131.0e-3;

    AB=sqrt(2.0*131.0e-3^2);

    AC=sqrt(72.0e-3^2+92.63e-3^2);

    CAB=atan(72.0e-3/92.63e-3);

    B1B=sqrt(OB1.^2+OB.^2-2.0.*OB1.*OB.*cos(XTA-pi/4.0));

    BB1O=(pi-(XTA-pi/4.0))/2.0;

    OBB1=(pi-(XTA-pi/4.0))/2.0;

    BB1A=pi/2.0+BB1O;

    B1AB=asin(B1B./AB.*sin(BB1A));

    ABB1=pi-BB1A-B1AB;

    OBA=OBB1-ABB1;

    AO=sqrt(AB.^2+OB.^2-2.0.*AB.*OB.*cos(OBA));

    AB1=sqrt(AO.^2-OB1.^2);

    S16=AB-AB1;

    BTA=XTA-pi/4.0;

    ALF=OBA;

    VB=OB.*OMGA;

    VP16=VB.*sin(ALF)./sin(pi-ALF-BTA);

    VZ=VB.*sin(BTA)./sin(pi-ALF-BTA);

    OMGAZ=VZ./AB;

    CAB1=CAB-B1AB;

    GMA=pi-(pi/2.0-CAB1);

    VC=sqrt(VP16.^2+(OMGAZ.*AC).^2-2.0.*VP16.*(AC.*OMGAZ).*cos(GMA));

    ALFG=pi/2.0+asin(AC.*OMGAZ.*sin(GMA)./VC);

    RJ16=RM16.*(VC./OMGA).^2+RJ16.*(OMGAZ./OMGA).^2;

    F16=RM16.*9.8.*VC.*cos(ALFG)./OMGA;

    FM16=-0.5.*RM16.*9.8.*U.*VP16./OMGA;

end

%弹筒17的运动规律，认为弹筒17在0——45°范围内作平面运动，在45——90°范围内作定轴转动：

RM17=68.8398;

RJ17=0.294227;

U=0.15;

%0——45°

HOB1=pi/4.0;

OB=131.0e-3;

AB=sqrt(2.0*131.0e-3^2);

OH=131.0e-3;

A1O=158.1565e-3;

CAB=atan(72.0e-3/92.63e-3);

AC=sqrt(72.0e-3^2+92.63e-3^2);

OC=72.0e-3+92.63e-3;

A1OC1=pi/4.0;

if XTA<=(pi/4.0);

    BTA=XTA+HOB1;

    EB=OB.*sin(BTA);

    OE=OB.*cos(BTA);

    BD=OH-OE;

    AD=sqrt(AB.^2-BD.^2);

    AH=AD-EB;

    AO=sqrt(AH.^2+OH.^2);

    OBA=acos((OB.^2+AB.^2-AO.^2)./(2.0.*OB.*AB));

    ALF=OBA;

    A1H=sqrt(A1O.^2-OH.^2);

    S17=A1H-AH;

    VB=OB.*OMGA;

    VZ=VB.*sin(BTA)./sin(pi-ALF-BTA);

    OMGAZ=VZ./AB;

    VP=VB.*sin(ALF)./sin(pi-ALF-BTA);

    CAD=CAB-asin(BD./AB);

    GMA=pi-(pi/2.0-CAD);

    VC=sqrt(VP.^2+(OMGAZ.*AC).^2-2.0.*VP.*(AC.*OMGAZ).*cos(GMA));

    ALFG=pi./2.0+acos((VP.^2+VC.^2-(AC.*OMGAZ).^2)./(2.0.*VC.*VP));

    RJ17=RM17.*(VC./OMGA).^2+RJ17.*(OMGAZ./OMGA).^2;

    F17=RM17.*9.8.*VC.*cos(ALFG)./OMGA;

    FM17=-RM17.*9.8/2.0.*U.*VP./OMGA;

else

    %45——90°

    OMGAZ2=OMGA;

    ALF2=A1OC1+XTA-pi/4.0;

    VC2=OC.*OMGA;

    ALFG2=pi/2.0+ALF2;

    RJ17=RM17.*(VC2./OMGA).^2+RJ17.*(OMGAZ2./OMGA).^2;

    F17=RM17.*9.8.*VC2.*cos(ALFG2)./OMGA;

    FM17=0.0;

end

%弹筒18的运动规律，认为弹筒18在0——45°内作定轴转动，在45——90°内作平面运动：

RM18=68.8398;

RJ18=0.294227;

U=0.15;

%0——45°

OC=72.0e-3+185.26e-3/2.0;

C1OH=0.0;

OA=131.0e-3;

B1O=131.0e-3;

BA=185.26e-3;

ABC=atan(72.0e-3/92.63e-3);

BC=sqrt(72.0e-3^2+92.63e-3^2);

ALF2=0.0;

if XTA<=(pi/4.0);