In some aspects, a control algorithm is provided for manipulating a pair of articulation arms configured to control an articulation angle of an end effector of a robotic surgical instrument. Other aspects of the present disclosure focus on the robotic arm system, including the pair of articulation arms coupled to the end effector and guided by independent motors controlled by a control circuit. Each of the articulation arms are designed to exert antagonistic forces competing against each other that are apportioned according to a ratio specified in the control algorithm. The ratio of the antagonistic forces may be used to determine the articulation angle of the head or end effector of the robotic surgical arm.