An apparatus includes a robotic coupling base configured to selectively coupled with a robotic arm of a robotic surgical system. A shaft extends distally from the robotic coupling base. The shaft includes a distal portion dimensioned to be inserted into a naturally occurring orifice of a patient. A remote center of motion (RCM) measuring feature is associated with the robotic coupling base or the shaft, the RCM measuring feature being configured to communicate with the robotic surgical system while the robotic coupling based is selectively coupled with the robotic arm. The RCM measuring feature is configured to measure a distance between an entry point of the naturally occurring orifice of the patient and a predetermined location of the apparatus. The RCM measuring feature is further configured to communicate the distance to the robotic surgical system.