∑ ∑ j = 1 n M i j ( q ) q ¨ ¨ j + ∑ ∑ j , k = 1 n Γ Γ i j k q ˙ ˙ j q ˙ ˙ k + ∂ ∂ V ∂ ∂ q i = Υ Υ i ; i = 1 , … … , n , where M is the "manipulator inertia matrix" and V is the potential energy due to gravity (for example), and Υ Υ i are the generalized forces on joint i. The terms involving Christoffel symbols therefore determine the "generalized centrifugal" and "generalized Coriolis" terms.