A model for constrained motion of a serial link manipulator

The equations of motion for a constrained mechanical system are derived from D´Alembert´s principle utilizing Lagrange multipliers. An explicit expression for the Lagrange multipliers is developed and their physical significance is explained. It is also suggested, how frictional effects can be simply incorporated into the model. The theory is applied to a serial link manipulator, whose tool tip is moving on a frictional surface.