Abstract:
A medical instrument including a shaft and an actuated structure mounted at a distal end of the shaft can employ a pair of tendons connected to the actuated structure, extending down the shaft, and respectively wound around a capstan in opposite directions. A passive preload system may maintain minimum tensions in the tendons.
Abstract:
Methods, apparatus, and systems for controlling the movement of a mechanical body. In accordance with a method, desired movement information is received that identifies a desired motion of a mechanical body, the mechanical body having a first number of degrees of freedom. A plurality of instructions are then generated by applying the received desired movement information to a kinematic model, the kinematic model having a second number of degrees of freedom greater than the first number of degrees of freedom, each of the instructions being configured to control a corresponding one of the second number of degrees of freedom. A subset of the plurality of instructions are then transmitted for use in controlling the first number of degrees of freedom of the mechanical body.
Abstract:
Methods, apparatus, and systems for controlling the movement of a mechanical body. In accordance with a method, desired movement information is received that identifies a desired motion of a mechanical body, the mechanical body having a first number of degrees of freedom. A plurality of instructions are then generated by applying the received desired movement information to a kinematic model, the kinematic model having a second number of degrees of freedom greater than the first number of degrees of freedom, each of the instructions being configured to control a corresponding one of the second number of degrees of freedom. A subset of the plurality of instructions are then transmitted for use in controlling the first number of degrees of freedom of the mechanical body.
Abstract:
Control systems and methods for a medical instrument use measurements to determine and control the tensions that actuators apply through instrument transmission systems. The use of tension and feedback allows control of a medical instrument having transmission systems that provide non-negligible compliance between joints and actuators even when the positions of joints cannot be directly related to actuator positions. One embodiment determines joint torques and tensions from differences between desired and measured joint positions. Another embodiment determines joint torques and tensions from differences between desired and measured positions of a tip of the instrument. Determination of tensions from joint torques can be performed using sequential evaluation of joints in an order from a distal end of the instrument toward a proximal end of the instrument.
Abstract:
A system comprises a flexible instrument, an input device, an insertion drive system comprising a drive motor, and a control system configured to selectively switch between a computer assisted mode and a manual mode. In the computer assisted mode, the control system causes the drive motor to move the flexible instrument along an insertion axis in response to one or more signals received from the input device. In the manual mode, the control system causes the drive motor to become off or inactive to allow the flexible instrument to be manually moved along the insertion axis.
Abstract:
A robotic medical system with a flexible guide tube such as a lung catheter can record the shape of the guide tube in a target configuration. If the shape includes a bend that is sharper than a sharpest permitted bend for insertion or removal of a tool such as a biopsy needle, a control system can find any locations of sharp bends and automatically retract the guide tube to a location associated with a sharp bend. With the tip backed up to that location, the needle can be inserted into or removed from the catheter. The control system can automatically move the catheter between the target configuration and the retracted configuration of the guide tube.
Abstract:
A medical system including a flexible instrument such as a lung catheter or bronchoscope provides a control mode in which direct manual control of insertion can be used with computer-assisted control of instrument characteristics such as the orientation or rigidity of a portion of the instrument. To facilitate manual insertion control, a mechanism can provide low inertia and friction for movement along an insertion axis. One implementation employs a manual grip of the instrument for control of insertion pressure, a joystick or other input device for computer-assisted steering, and a foot pedal for control of stiffness or compliance in the instrument. Another implementation employs a joystick for computer-assisted steering and for control of stiffness or compliance in the instrument.
Abstract:
A medical system comprising a medical instrument including at least one elongated actuation member used to move at least a portion of the medical instrument, a motor coupled to the medical instrument and used to operate the at least one elongated actuation member, and a control system in communication with the medical instrument and with the motor. The control system is configured to receive at least one input from the medical instrument and determine a force on a tip of the medical instrument by applying the at least one input to a lumped model of the medical instrument. The lumped model comprises a mass of the motor and a spring parameter coupling the mass of the motor to a mass of the portion of the medical instrument.
Abstract:
A system includes a flexible guide tube, an actuator coupled to the flexible guide tube and configured to move at least a portion of the flexible guide tube, a processor, and memory storing computer-executable instructions. When executed by the processor, the computer-executable instructions cause the system to: identify at least one factor associated with insertion or removal of a tool configured to be inserted through or removed from the flexible guide tube; identify, in a first configuration of the flexible guide tube and based on the at least one factor, one or more sections of the flexible guide tube having one or more bends that the tool cannot traverse; and command the actuator to automatically move the flexible guide tube to a second configuration without manual steering by a user, wherein the second configuration does not include the one or more bends that the tool cannot traverse.
Abstract:
A medical device comprises a tube including a wall with a plurality of slits oriented generally transverse to a longitudinal axis of the tube and defined by opposing surfaces. A pair of force transmission elements is actuatable to alter the tube between a flexible state and a stiffened state. A first force transmission element of the pair is coupled to an opposite side of the tube from the second force transmission element of the pair. The surgical device also includes a plurality of routing members coupled to the wall of the tube and configured to receive and route the force transmission elements along a length of the tube while permitting the length of the tube to flex and compress. Equal tension forces applied to the pair of force transmission elements compress the tube to create the stiffened state by deforming regions of the tube disposed between the plurality of slits.