message: adds comment about damping ratio
diff: @@ -189,6 +189,7 @@ void CartesianImpedanceExampleController::update(const ros::Time& /*time*/,
  pseudo_inverse(jacobian.transpose(), jacobian_transpose_pinv);
  tau_task << jacobian.transpose() * (-cartesian_stiffness_ * error - cartesian_damping_ * dx_);
  + // nullspace PD control with damping ratio = 1
  tau_nullspace << (Eigen::MatrixXd::Identity(7, 7) -
  jacobian.transpose() * jacobian_transpose_pinv) *
  (nullspace_stiffness_ * (q_d_nullspace_ - q) -
  