function [qtilde tau] = cap8_atanflor8p(t,x,xp)
q = [x(1); x(2)];   %posiciones
qp = [xp(1); xp(2)]; %velocidades

kp1=100; kp2=15; kv1=kp1;kv2=kp2;
Kp=[kp1, 0; 0, kp2];  %ganancia proporcional
Kv=[kv1,  0; 0, kv2]; %ganancia derivativa
lambda1=180/pi; 
lambda2=180/pi; 
Lambda=[lambda1 0;
        0 lambda2];
gamma1=1; 
gamma2=1; 
Gamma=[gamma1 0; 
        0 gamma2];
  
par_grav = [38.46*sin(q(1))+1.82*sin(q(1)+q(2)); %vector de pares de gravitacionales
               1.82*sin(q(1)+q(2))       ];

xc=0.3; yc=0.3; r=0.2; l1=0.45; l2=0.45; alfa=0.07; beta=4;  
x=xc+alfa+r*(cos(t))*(sin(beta*t));
y=-yc+alfa+r*(sin(t))*(sin(beta*t));  
[qd1 qd2]=cinv_r2gdl(l1,l2,x,y);

qd=[qd1; qd2];

qtilde=[qd(1)-q(1); qd(2)-q(2)];   %error de posición
 
%ley de control atan
 tau=Kp*atan(Lambda*qtilde)-Kv*atan(Gamma*qp)+par_grav;
end