function GRF = RobGRF( A,M,go )

 Mt = sum(M);
 m0 = M(1);  m1 = M(2);  m2 = M(3);

%-- Ground reaction forces ------------------------------------------------
 GRF(1) = m0*A(1,1)+m1*A(2,1)+m2*A(3,1);
 GRF(2) = m0*A(1,2)+m1*A(2,2)+m2*A(3,2);
 GRF(3) = m0*A(1,3)+m1*A(2,3)+m2*A(3,3)+go*Mt;
%-----------------------------------------------------------------------end
 GRF = GRF';
end