Surgical Robot End Effector With Quick-Load Cutting Accessory Coupling

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Solution Overview

Problem

Existing surgical robotic manipulators face challenges in efficiently and easily attaching and detaching cutting accessories, which can interfere with surgical access and require complex locking mechanisms, complicating semi-autonomous operations.

Innovation Solution

The end effector of a surgical robotic manipulator features a nose tube with a clutch assembly and axial, drive connectors that allow for quick and precise attachment and detachment of cutting accessories, reducing bulk and improving access, while enabling semi-autonomous operation through a lever mechanism and sensor feedback.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If complex locking mechanisms are used to securely attach cutting accessories, then reliability of attachment is improved, but device complexity increases

Engineering Contradiction:

Improveattachment reliabilityVSAvoidlocking mechanism complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces complex mechanical locking mechanisms with a magnetic coupling system. The nose tube contains a magnet that magnetically couples with a ferromagnetic material in the cutting accessory, enabling secure attachment without complex mechanical locks. This substitution maintains attachment reliability while significantly reducing mechanism complexity.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent changes the attachment mechanism from mechanical interlocking to magnetic field interaction. By utilizing magnetic field strength as the attachment parameter instead of mechanical engagement, the system achieves reliable attachment with simpler components. The magnetic force can be controlled by adjusting magnet strength and positioning.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If larger locking mechanisms are used to secure cutting accessories, then attachment reliability is improved, but surgical access is worsened due to increased bulk

Engineering Contradiction:

Improveattachment reliabilityVSAvoidend effector bulk

Core Design Contradiction:

ReliabilityVSVolume of moving object

Solution Approach 1:

The magnetic coupling system eliminates the need for large mechanical locking components. The magnet embedded in the nose tube and ferromagnetic material in the cutting accessory create a compact attachment system that maintains reliability without increasing end effector bulk, thereby preserving surgical access.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Productivity

If manual attachment procedures are used, then device complexity is reduced, but productivity decreases due to time-consuming attachment and detachment

Engineering Contradiction:

Improveattachment speedVSAvoidattachment mechanism complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The magnetic coupling system allows for rapid attachment by simply bringing the cutting accessory near the nose tube, where magnetic attraction automatically secures it. Detachment is equally simple by overcoming the magnetic force. This eliminates time-consuming manual locking procedures while keeping the mechanism simple.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The magnetic coupling system provides self-aligning and self-securing functionality. When the cutting accessory approaches the nose tube, the magnetic field automatically guides and secures the attachment without requiring precise manual alignment or activation of locking mechanisms, thereby increasing attachment speed.

Inventive Principle:

Principle #25Self-service

4Reliability

If complex locking mechanisms are used, then attachment reliability is improved, but ease of operation is worsened

Engineering Contradiction:

Improveattachment reliabilityVSAvoidattachment ease

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The magnetic coupling system replaces complex manual locking operations with simple magnetic attraction. The operator only needs to bring the cutting accessory close to the nose tube for automatic magnetic engagement, making the operation intuitive and easy while maintaining secure attachment.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The magnetic system performs the attachment function automatically through magnetic attraction when components are brought into proximity. This self-securing mechanism eliminates the need for operators to manipulate complex locking mechanisms, significantly improving ease of operation while ensuring reliable attachment.

Inventive Principle:

Principle #25Self-service

Data Source

PatentEP4446070B1End effector of a surgical robotic manipulator

Publication Date: 2026.03.25 STRYKER CORP

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AI summary

An end effector of a surgical robotic manipulator comprises a nose tube extending along an axis, a rotatable cutting accessory releasably coupled to the nose tube for cutting tissue of a patient, an actuator coupled to the cutting accessory when the cutting accessory is coupled to the nose tube for rotatably driving the cutting accessory, a removeable guard releasably coupled to the cutting accessory for covering a portion of the cutting accessory, a first circuit mounted to one of the cutting accessory or the removable guard, and a second circuit mounted to the nose tube. The first circuit and the second circuit are configured to communicate with each other. Also disclosed is a method of assembling a cutting accessory to an end effector of a surgical robotic manipulator with the use of a guard that removeably covers a portion of the cutting accessory.