Surgical End Effector Cable Folding for Compact Diameter
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surgical robot systems face challenges in reducing the diameter and size of the surgical tool unit, which limits the compact arrangement of surgical tool units and the robotic system, and hinders precise automatic replacement of surgical tools during surgery.
Innovation Solution
The proposed solution involves an end effector unit with a cable and pulley system that folds back the cable, connected to a linear motion transmission device with one degree of freedom, allowing for a compact layout that reduces the diameter and size of the surgical tool unit. This configuration includes a rotation suppression device to prevent rod rotation, enabling precise linear motion transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of moving object
If a conventional cable transmission layout is used, then the surgical tool unit can transmit driving force, but the diameter and size of the surgical tool unit become large
Solution Approach 1:
The patent applies dimensionality change by transitioning from a conventional planar cable layout to a three-dimensional folded cable configuration. The cable is folded back multiple times in different spatial dimensions, allowing the transmission path to utilize vertical and radial spaces more efficiently. This dimensional reorganization reduces the overall diameter and volume of the surgical tool unit while maintaining the cable transmission function.
Solution Approach 2:
The patent implements nesting by arranging the cable folds and pulleys in a compact, concentric configuration. The cable is folded back multiple times with each fold nested within the space created by the previous fold, similar to nested dolls. This nested arrangement maximizes space utilization and minimizes the external dimensions of the surgical tool unit.
2Length of stationary object
If the linear motion transmission device is positioned away from the center, then the cable layout is simpler, but the diameter of the surgical tool unit increases
Solution Approach 1:
The patent applies segmentation by dividing the cable transmission path into multiple discrete folded segments. Each fold creates a separate transmission path segment that can be independently positioned and secured. This segmentation allows the cable to be routed through precise intervals around the longitudinal axis, enabling the linear motion transmission device to be positioned close to the center while maintaining manufacturability through standardized folding patterns.
3Manufacturing precision
If the rod is allowed to rotate freely, then the linear motion transmission is simpler, but the precision of force transmission is reduced
Solution Approach 1:
The patent introduces a rotation suppression mechanism as an intermediary component between the linear motion transmission device and the cable connection. This intermediary device prevents rotational movement of the rod while allowing linear motion, thereby ensuring precise force transmission along the cable's transmission path. The rotation suppression mechanism acts as a mediator that decouples rotational and linear degrees of freedom.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces the size and diameter of the surgical tool unit, facilitating a more compact arrangement of the robotic system and enabling accurate automatic replacement of surgical tools, thereby enhancing surgical precision and efficiency.
Implementation Method 1
a pulley configured to fold back the cable extending toward a root side in a tip end direction
Implementation Method 2
a linear motion transmission device having one degree of freedom in linear traveling in a longitudinal direction and connected to the other end of the cable folded back by the pulley
Data Source
AI summary
Provided is an end effector unit that is exchangeably attached to a drive unit and operates by a driving force transmitted from the drive unit. The end effector unit includes a cable having one end on a tip end side connected to an end effector, a pulley configured to fold back the cable extending toward a root side in a tip end direction, and a linear motion transmission device having one degree of freedom in linear traveling in a longitudinal direction and connected to the other end of the cable folded back by the pulley. The linear motion transmission device and the pulley are alternately arranged in a circumferential direction around a longitudinal axis, and are reduced in size and diameter.