Retention Assembly for Surgical Instrument End Effector Positioning
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing articulating remote access tools, such as handheld surgical instruments, face challenges in accurately controlling the position and orientation of the end effector during minimally invasive surgical procedures, particularly when inserting the device into a trocar, due to the need for additional support and the complexity of locking mechanisms.
Innovation Solution
A retention assembly that includes a first body, a second body, one or more joints, and a retention body, which can be moved between a first position and a second position to partially or more constrain the degrees of freedom between the first body and the second body, allowing for precise control of the end effector using only the input body.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a locking apparatus with locking units and unlocking units is used to lock the output body in position, then the position control precision is improved, but the device complexity increases due to indirect locking functionality acting on control members rather than rigid bodies
Solution Approach 1:
The patent extracts the locking function from complex multi-unit locking/app unlocking mechanisms and implements it through a simpler retention body that can be moved between positions to directly constrain the articulating joint. This reduces the number of components while maintaining the locking capability.
Solution Approach 2:
Instead of using locking units that act on control members indirectly, the patent inverts the approach by having the retention body directly constrain the articulating joint's rigid bodies. This direct action simplifies the mechanism while achieving the same position control precision.
2Measurement precision
If additional support (opposite hand or nurse assistance) is used to control device position during insertion, then the position control precision is improved, but the ease of operation deteriorates due to requiring multiple hands or assistance
Solution Approach 1:
The patent enables the device to be self-sufficient during insertion by incorporating the retention body that can be operated from the handle to directly control and stabilize the end effector position. This eliminates the need for external assistance (opposite hand or nurse support) while maintaining precise position control.
3Stability of the object's composition
If the retention body is moved to the second position to constrain degrees of freedom, then the stability of the articulating joint is improved, but the ease of operation deteriorates due to requiring precise positioning control
Solution Approach 1:
The patent implements the retention body as a movable component that can dynamically transition between positions (first position for freedom of motion, second position for constraint). This dynamic capability allows the system to adapt between stability and operability as needed during different surgical tasks.
Solution Approach 2:
The retention body is periodically moved between constrained and unconstrained positions based on surgical needs. During insertion, it is positioned to constrain the joint for stability; during manipulation, it is moved to allow freedom of motion. This periodic switching optimizes both stability and ease of operation at different times.
Data Source
AI summary
A retention assembly is provided that can be equipped in a handheld surgical tool or instrument or other medical device, as well as potentially in non-medical devices, among other possible applications. In the application of the handheld surgical instrument, the retention assembly furnishes partial or more constraint between bodies such as a handle body and a frame body, which in turn serves to partially or more constrain an end effector of the handheld surgical instrument. Such constraint at the end effector, whether partial or full, can be useful in certain scenarios amid a minimally invasive surgical (MIS) procedure such as during initial insertion of the end effector through a surgical trocar at a patient's body.