CN-121971160-A - Dithering system and method for maintaining grip

Abstract

A dithering system and method for maintaining grip includes a computer-aided device. The computer-assisted device includes an instrument having a first jaw and a second jaw, the first jaw and the second jaw configured to grasp a material, one or more actuators configured to actuate the first jaw and the second jaw to apply a force to the grasped material, and a controller coupled to the one or more actuators. The controller is configured to determine that actuation of the one or more actuators should be dithered, and in response to the determination, dither the one or more control signals to the one or more actuators to cause a change in a force or torque applied by the one or more actuators. In some embodiments, the one or more control signals correspond to a force set point, a torque set point, a current set point, or a position set point for the one or more actuators.

Inventors

• A. Lat
• B. D. SAII

Assignees

• 直观外科手术操作公司

Dates

Publication Date

20260505

Application Date

20200910

Priority Date

20190911

Claims (10)

1. 1. A computer-assisted device, comprising: An instrument having a first jaw and a second jaw configured to grasp a material; one or more actuators configured to actuate the first jaw and the second jaw to apply a force to the gripped material, and A controller coupled to the one or more actuators; Wherein the controller is configured to: determining that actuation of the one or more actuators should be dithered, and Responsive to the determination, dithering one or more control signals to the one or more actuators to cause a change in a force or torque applied by the one or more actuators.
2. 2. The computer-assisted device of claim 1, wherein the material is body tissue.
3. 3. The computer-assisted device of claim 1, wherein the one or more control signals correspond to a force setting of the one or more actuators, a torque setting of the one or more actuators, a current setting of the one or more actuators, or a position setting of the one or more actuators.
4. 4. The computer-assisted device of claim 1, wherein the controller is further configured to determine the force applied to the gripped material using one or more sensors on the first and second jaws or on one or more drive mechanisms coupling the one or more actuators to the first and second jaws.
5. 5. The computer-assisted device of claim 1, wherein the jitter is superimposed on the one or more control signals.
6. 6. The computer-assisted device of claim 1, wherein the jitter is applied as a sine wave, a square wave, a triangle wave, a sawtooth wave, or a combination of two or more waves.
7. 7. The computer-assisted device of claim 1, wherein the amplitude of the jitter is a percentage of a set point for a corresponding one of the one or more control signals.
8. 8. The computer-assisted device of claim 1, wherein the amplitude of the jitter is a percentage of a set point limit for a respective one of the one or more control signals.
9. 9. The computer-assisted device of claim 1, wherein the amplitude of the jitter is limited to not violate one or more set point limits of a corresponding one of the one or more control signals.
10. 10. The computer-assisted device of claim 1, wherein the jitter is asymmetric about a set point of a corresponding one of the one or more control signals.

Description

Dithering system and method for maintaining grip The application is a divisional application of Chinese patent application 2020800608025 (PCT/US 2020/050132) entitled "shaking System and method for maintaining grip" filed on 9/10/2020. RELATED APPLICATIONS The present application claims the benefit of U.S. provisional application No. 62/899,085 entitled, "SYSTEM AND Method of Dithering to MAINTAIN GRASP Force," filed on 9, 11, 2019, which is incorporated herein by reference. Technical Field The present disclosure relates generally to operation of devices having repositionable arms and instruments, and more particularly to operation of grasping instruments that use dithering to maintain a consistent grasping force and prevent excessive force generation. Background More and more devices are being replaced by computer-aided electronic devices. This is especially true in industrial, recreational, educational and other settings. As a medical example, today's hospitals find a large number of electronic devices in operating rooms, intervention rooms, intensive care units, emergency rooms and/or the like. For example, glass and mercury thermometers are being replaced with electronic thermometers, intravenous drip lines now include electronic monitors and flow regulators, and traditional hand-held surgical and other medical devices are being replaced with computer-assisted medical devices. These computer-assisted devices are useful for performing operations and/or procedures on materials located in a workspace (e.g., a patient's body tissue). With many computer-assisted devices, an operator (e.g., a surgeon in a medical example) can remotely control the computer-assisted device using one or more controls on an operator console. As the operator manipulates various controls on the operator console, commands are forwarded from the operator console to equipment in or near the workspace to which one or more end effectors and/or instruments are mounted. In this way, an operator can perform one or more procedures on a material or object in a workspace using the end effector and/or instrument. Depending on the desired procedure and/or the instrument used, the desired procedure may be performed in part or in whole under control of the operator using a remote control and/or under semi-automatic control, wherein the instrument may perform or alter the sequence of operations based on one or more activation actions of the operator. Instruments of different designs and/or configurations may be used to perform different tasks, procedures, and/or functions to allow an operator to perform any of a variety of procedures. Computer-assisted instruments, whether manually, remotely controlled, and/or semi-automatically actuated, may be used for various operations and/or procedures, and may have various configurations. Many such instruments include an end effector mounted at the distal end of a shaft that may be mounted to the distal end of a repositionable arm. In many operating scenarios, the shaft may be configured to be inserted (e.g., laparoscopically, thoracoscopically, and/or the like) through an opening (e.g., a body wall incision, a natural orifice, an access port, and/or the like) to reach a remote location within the workspace. In some instruments, an articulating wrist mechanism may be mounted to the distal end of the instrument shaft to support the end effector, wherein the articulating wrist provides the ability to alter the orientation of the end effector relative to the longitudinal axis of the shaft. Examples of such instruments include, but are not limited to, cautery, ablation, suturing, cutting, stapling, fusing, sealing, and the like, and/or combinations thereof. Thus, the instrument may include various components and/or combinations of components to perform these procedures. When access to the workspace is limited, the size and/or strength of the instrument may be limited. As a medical example, when a computer-assisted device is used to perform a minimally invasive surgical procedure, the instrument may have to be fitted through a body orifice and/or a body wall incision that is kept as small as possible to reduce the impact on the patient. In another example, when the workspace is contained (e.g., it is hazardous, climate controlled, sterile, and/or the like), access to the workspace may be controlled through one or more reduced-size apertures. Consistent with the goal of accessing a workspace having limited access, the size of the end effector is typically kept as small as possible while still allowing it to perform its intended tasks. One way to keep the end effector size small is by using one or more inputs at the proximal end of a surgical instrument that is typically located outside the patient's body to accomplish actuation of the end effector. Various gears, levers, pulleys, cables, rods, belts, and/or the like may then be used to conduct motion from one or more inputs along the shaft of the instrument and ac