Abstract: A compliant surgical device such as a flexible entry guide employs tendons to operate or steer the device and attaches asymmetric or constant force spring systems to control tension in the tendons. As a result, the surgical device can be compliant and respond to external forces during a surgical procedure without rapidly springing back or otherwise causing a reaction that damages tissue. The compliance also permits manual positioning or shaping of the device during or before insertion for a surgical procedure without damaging the tendons or connections of the tendons within the device or to a backend mechanism.

Abstract: A surgical system comprises a surgical instrument having distal and proximal portions. The surgical system also comprises a reference fixture positioned in a first reference frame and a shape sensor extending from the distal portion through the proximal portion to the reference fixture. The surgical system also comprises a processor configured to perform a registration step to register the first reference frame to a fixed world reference frame. The registration step includes receiving a set of shape information of the shape sensor with a distal point of the surgical instrument located at a patient reference point. A first portion of the shape sensor is in a known geometrical shape at a fixed location along a length of the shape sensor. The registration step also includes computing a location of the patient reference point and computing a pose of the first reference frame relative to the fixed world reference frame.

Abstract: A compliant surgical device such as a flexible entry guide employs tendons to operate or steer the device and attaches asymmetric or constant force spring systems to control tension in the tendons. As a result, the surgical device can be compliant and respond to external forces during a surgical procedure without rapidly springing back or otherwise causing a reaction that damages tissue.

Abstract: A compliant surgical device such as a flexible entry guide employs tendons to operate or steer the device and attaches asymmetric or constant force spring systems to control tension in the tendons. As a result, the surgical device can be compliant and respond to external forces during a surgical procedure without rapidly springing back or otherwise causing a reaction that damages tissue. The compliance also permits manual positioning or shaping of the device during or before insertion for a surgical procedure without damaging the tendons or connections of the tendons within the device or to a backend mechanism.

Abstract: An apparatus includes a reference fixture. The reference fixture includes a joint, and a joint tracker to track motion of the joint. The apparatus also includes a surgical instrument. A tether is connected between the joint and the surgical instrument. A shape sensor extends from the reference fixture through the joint, through the tether, and into the surgical instrument. The shape sensor is substantially free of twist. The joint tracker measures the motion of the joint. Information from the shape sensor in combination with information from the joint tracker provides absolute three-dimensional information relative to the reference fixture, i.e., provides absolute three-dimensional information in a fixed world reference frame.

Abstract: A system comprises a medical instrument including a rotatable capstan. The rotatable capstan includes a first coupling feature and a drive system including a rotatable drive element. The rotatable drive element includes a second coupling feature. The first and second coupling features have an aligned engagement configuration in which rotation of the rotatable drive element induces rotation of the rotatable capstan and a non-aligned engagement configuration in which rotation of the rotatable drive element does not induce rotation of the rotatable capstan.

Abstract: An apparatus includes a reference fixture. The reference fixture includes a joint, and a joint tracker to track motion of the joint. The apparatus also includes a surgical instrument. A tether is connected between the joint and the surgical instrument. A shape sensor extends from the reference fixture through the joint, through the tether, and into the surgical instrument. The shape sensor is substantially free of twist. The joint tracker measures the motion of the joint. Information from the shape sensor in combination with information from the joint tracker provides absolute three-dimensional information relative to the reference fixture, i.e., provides absolute three-dimensional information in a fixed world reference frame.

Abstract: A medical robotic system includes an entry guide with articulatable instruments extending out of its distal end, an entry guide manipulator providing controllable four degrees-of-freedom movement of the entry guide relative to a remote center, and a controller configured to manage operation of the entry guide manipulator in response to operator manipulation of one or more input devices. As the entry guide manipulator approaches a yaw/roll singularity, the controller modifies its operation to allow continued movement of the entry guide manipulator without commanding excessive joint velocities while maintaining proper orientation of the entry guide.

Abstract: A robotic surgical system uses a passive preload system attached to a tendon that is wrapped around a capstan to control relaxed tension in the tendon. The passive preload system can employ a spring or other structure to apply tension to the tendon. The capstan can be driven by a motor when the tendon is needed to pull on a structural member of the instrument. For example, for the application of clamping pressure or movement of the structural member against resistance, capstan friction can produce the tendon tension that is many times the tension applied by the passive preload system. However, when the tendon is not needed to apply force to the member, the capstan can be freed, so that the spring system provides enough tension to prevent derailment or other malfunctions of the tendon. The low tension in relaxed tendons can reduce tendon friction, particularly in instruments with flexible shafts.

Abstract: An apparatus includes a reference fixture. The reference fixture includes a joint, and a joint tracker to track motion of the joint. The apparatus also includes a surgical instrument. A tether is connected between the joint and the surgical instrument. A shape sensor extends from the reference fixture through the joint, through the tether, and into the surgical instrument. The shape sensor is substantially free of twist. The joint tracker measures the motion of the joint. Information from the shape sensor in combination with information from the joint tracker provides absolute three-dimensional information relative to the reference fixture, i.e., provides absolute three-dimensional information in a fixed world reference frame.

Abstract: An apparatus includes a reference fixture. The reference fixture includes a joint, and a joint tracker to track motion of the joint. The apparatus also includes a surgical instrument. A tether is connected between the joint and the surgical instrument. A shape sensor extends from the reference fixture through the joint, through the tether, and into the surgical instrument. The shape sensor is substantially free of twist. The joint tracker measures the motion of the joint. Information from the shape sensor in combination with information from the joint tracker provides absolute three-dimensional information relative to the reference fixture, i.e., provides absolute three-dimensional information in a fixed world reference frame.

Abstract: An apparatus includes a reference fixture. The reference fixture includes a joint, and a joint tracker to track motion of the joint. The apparatus also includes a surgical instrument. A tether is connected between the joint and the surgical instrument. A shape sensor extends from the reference fixture through the joint, through the tether, and into the surgical instrument. The shape sensor is substantially free of twist. The joint tracker measures the motion of the joint. Information from the shape sensor in combination with information from the joint tracker provides absolute three-dimensional information relative to the reference fixture, i.e., provides absolute three-dimensional information in a fixed world reference frame.

Abstract: A robotic surgical system uses a passive preload system attached to a tendon that is wrapped around a capstan to control relaxed tension in the tendon. The passive preload system can employ a spring or other structure to apply tension to the tendon. The capstan can be driven by a motor when the tendon is needed to pull on a structural member of the instrument. For example, for the application of clamping pressure or movement of the structural member against resistance, capstan friction can produce the tendon tension that is many times the tension applied by the passive preload system. However, when the tendon is not needed to apply force to the member, the capstan can be freed, so that the spring system provides enough tension to prevent derailment or other malfunctions of the tendon. The low tension in relaxed tendons can reduce tendon friction, particularly in instruments with flexible shafts.

Abstract: A medical robotic system has a joint coupled to medical device or a slave manipulator or robotic arm adapted to hold and/or move the medical device for performing a medical procedure, and a control system for controlling movement of the joint according to user manipulation of a master manipulator. The control system includes at least one joint controller having a sliding mode control for reducing stick-slip behavior on its controlled joint during fine motions of the joint. The sliding mode control computes a distance to a sliding surface, computes a reaching law gain, and processes the distance and reaching law gain to generate a sliding mode control action that is in absolute value less that a maximum desired feedback control action. The sliding mode control action is then further processed to generate a feedback torque command for the joint motor.

Abstract: A medical robotic system has a joint coupled to medical device or a slave manipulator or robotic arm adapted to hold and/or move the medical device for performing a medical procedure, and a control system for controlling movement of the joint according to user manipulation of a master manipulator. The control system includes at least one joint controller having a sliding mode control for reducing stick-slip behavior on its controlled joint during fine motions of the joint. The sliding mode control computes a distance to a sliding surface, computes a reaching law gain, and processes the distance and reaching law gain to generate a sliding mode control action that is in absolute value less that a maximum desired feedback control action. The sliding mode control action is then further processed to generate a feedback torque command for the joint motor.

Abstract: A robotic surgical system includes a master controller with an input handle and robotic manipulator assemblies including a surgical end effector and an endoscopic camera. The input handle is translatable to provide a position and rotatable to provide an orientation. A control system couples the master controller to the first and second manipulator assemblies. The control system moves the surgical end effector in response to the position and orientation of the input handle. The control system moves the input handle to orient the input handle to correspond to an orientation of the surgical end effector from a viewpoint of the endoscopic camera during the repositioning of at least one of the input handle position, the end effector, or the endoscopic camera. The control system may move the surgical end effector only in a first mode and orients the input handle only in a second mode.

Abstract: A medical robotic system includes an entry guide with articulatable instruments extending out of its distal end, an entry guide manipulator providing controllable four degrees-of-freedom movement of the entry guide relative to a remote center, and a controller configured to manage operation of the entry guide manipulator in response to operator manipulation of one or more input devices. As the entry guide manipulator approaches a yaw/roll singularity, the controller modifies its operation to allow continued movement of the entry guide manipulator without commanding excessive joint velocities while maintaining proper orientation of the entry guide.

Abstract: A medical robotic system includes an entry guide with articulatable instruments extending out of its distal end, an entry guide manipulator providing controllable four degrees-of-freedom movement of the entry guide relative to a remote center, and a controller configured to manage operation of the entry guide manipulator in response to operator manipulation of one or more input devices. As the entry guide manipulator approaches a yaw/roll singularity, the controller modifies its operation to allow continued movement of the entry guide manipulator without commanding excessive joint velocities while maintaining proper orientation of the entry guide.

Abstract: An apparatus includes a reference fixture. The reference fixture includes a joint, and a joint tracker to track motion of the joint. The apparatus also includes a surgical instrument. A tether is connected between the joint and the surgical instrument. A shape sensor extends from the reference fixture through the joint, through the tether, and into the surgical instrument. The shape sensor is substantially free of twist. The joint tracker measures the motion of the joint. Information from the shape sensor in combination with information from the joint tracker provides absolute three-dimensional information relative to the reference fixture, i.e., provides absolute three-dimensional information in a fixed world reference frame.

Abstract: A medical robotic system has a joint coupled to medical device or a slave manipulator or robotic arm adapted to hold and/or move the medical device for performing a medical procedure, and a control system for controlling movement of the joint according to user manipulation of a master manipulator. The control system includes at least one joint controller having a sliding mode control for reducing stick-slip behavior on its controlled joint during fine motions of the joint. The sliding mode control computes a distance to a sliding surface, computes a reaching law gain, and processes the distance and reaching law gain to generate a sliding mode control action that is in absolute value less that a maximum desired feedback control action. The sliding mode control action is then further processed to generate a feedback torque command for the joint motor.