A medical instrument system comprising a medical instrument, the medical instrument comprising a tip, the system including: a plurality of joints; a plurality of actuators; a plurality of transmission systems having proximal ends respectively coupled to the plurality of actuators, each transmission system of the plurality of transmission systems having a distal end attached to an associated joint of the plurality of joints to allow transmission of a force for articulation of the medical instrument; a sensor (260, 360) coupled to measure a configuration of the medical instrument, the configuration comprising a position of the tip of the medical instrument; and a control system configured to perform operations comprising: receiving configuration data, including a current position of the tip of the medical instrument from the sensor, and including a desired position of the tip of the medical instrument, determining a difference between the current position and the desired position of the tip of the medical instrument, determining, from the difference and using one or more gain factors specifying dynamic behavior of the tip of the medical instrument and one or more parameters selected according to a desired responsiveness of the plurality of joints, a tip force and a tip torque that when applied to the tip of the medical instrument moves the tip of the medical instrument from the current position toward the desired position, determining joint torques for one or more of the plurality of joints that produce the determined tip force and the determined tip torque using a Jacobian matrix that depends on geometry of the medical instrument system and positions of the plurality of joints, determining a set of tensions based on the determined joint torques and geometry or mechanics between the plurality of joints and the plurality of transmission systems, and generating control signals for at least one of the plurality of actuators that cause the at least one of the plurality of actuators to apply the determined set of tensions to at least one of the plurality of transmission systems. a plurality of joints; a plurality of actuators; a plurality of transmission systems having proximal ends respectively coupled to the plurality of actuators, each transmission system of the plurality of transmission systems having a distal end attached to an associated joint of the plurality of joints to allow transmission of a force for articulation of the medical instrument; a sensor (260, 360) coupled to measure a configuration of the medical instrument, the configuration comprising a position of the tip of the medical instrument; and a control system configured to perform operations comprising: receiving configuration data, including a current position of the tip of the medical instrument from the sensor, and including a desired position of the tip of the medical instrument, determining a difference between the current position and the desired position of the tip of the medical instrument, determining, from the difference and using one or more gain factors specifying dynamic behavior of the tip of the medical instrument and one or more parameters selected according to a desired responsiveness of the plurality of joints, a tip force and a tip torque that when applied to the tip of the medical instrument moves the tip of the medical instrument from the current position toward the desired position, determining joint torques for one or more of the plurality of joints that produce the determined tip force and the determined tip torque using a Jacobian matrix that depends on geometry of the medical instrument system and positions of the plurality of joints, determining a set of tensions based on the determined joint torques and geometry or mechanics between the plurality of joints and the plurality of transmission systems, and generating control signals for at least one of the plurality of actuators that cause the at least one of the plurality of actuators to apply the determined set of tensions to at least one of the plurality of transmission systems. receiving configuration data, including a current position of the tip of the medical instrument from the sensor, and including a desired position of the tip of the medical instrument, determining a difference between the current position and the desired position of the tip of the medical instrument, determining, from the difference and using one or more gain factors specifying dynamic behavior of the tip of the medical instrument and one or more parameters selected according to a desired responsiveness of the plurality of joints, a tip force and a tip torque that when applied to the tip of the medical instrument moves the tip of the medical instrument from the current position toward the desired position, determining joint torques for one or more of the plurality of joints that produce the determined tip force and the determined tip torque using a Jacobian matrix that depends on geometry of the medical instrument system and positions of the plurality of joints, determining a set of tensions based on the determined joint torques and geometry or mechanics between the plurality of joints and the plurality of transmission systems, and generating control signals for at least one of the plurality of actuators that cause the at least one of the plurality of actuators to apply the determined set of tensions to at least one of the plurality of transmission systems.