function J=jacobianoRRR(Q,lb,l3)

a=Q(1);
b=Q(2);
c=Q(3);

J=[ -sin(a)*(l3*cos(b + c)-lb*sin(b))   -cos(a)*(l3*sin(b + c)+lb*cos(b)) -l3*sin(b + c)*cos(a)
     cos(a)*(l3*cos(b + c)-lb*sin(b))   -sin(a)*(l3*sin(b + c)+lb*cos(b)) -l3*sin(b + c)*sin(a)
                  0                      l3*cos(b + c)-lb*sin(b)           l3*cos(b + c)
];