A method of calibrating a delta robot, the method including executing an arm movement by moving one driving link relative to other two driving links; measuring a movement of a point in fixed relationship with a tilting body during the arm movement as an arm measurement; executing a tilting movement by tilting the tilting body about a fifth axis; measuring a movement of the point during the tilting movement as a tilting measurement; and calibrating a fourth axis based on a comparison of the arm measurement and the tilting measurement. A method of calibrating the fifth axis, a control system, and a robot system are also provided.