Two-Cable Hemispherical Grasper for Surgical Articulation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Endoscopic surgical devices face challenges in accessing and manipulating surgical sites due to limited access through small incisions, requiring sophisticated articulation mechanisms to orient tools effectively within the restricted space.
Innovation Solution
A surgical grasper with a two-cable hemispherical articulation assembly that includes jaws, actuation members, an articulation joint, and linkage members, allowing for pivoting and articulation in multiple planes, enabling a full hemispherical reach within the surgical site while minimizing the entrance opening size.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a two-cable hemispherical articulation assembly is used, then tool orientation flexibility and hemispherical reach are improved, but device complexity increases
Solution Approach 1:
The articulation assembly is divided into separate functional components: first and second articulation members, first and second linkage members, and an articulation joint. Each component performs a specific function in the hemispherical reach mechanism, allowing independent optimization and simplifying the overall system while maintaining full range of motion capability.
Solution Approach 2:
The system transitions from single-plane articulation to two-plane articulation by introducing a second articulation member that operates orthogonal to the first. This enables hemispherical reach by adding a second degree of freedom, allowing the tool to pivot both in the first plane and the second plane simultaneously.
2Force
If cable thickness is increased, then clamping force is improved, but device complexity and maneuverability through small incisions worsen
Solution Approach 1:
The cable routing is extracted and optimized by using the articulation joint and linkage members to redirect cables along favorable paths. The cables are routed through the articulation assembly in a manner that maximizes their mechanical advantage while minimizing the required cable diameter, allowing sufficient clamping force without excessive bulk.
Solution Approach 2:
The hemispherical articulation assembly uses curved cable routing paths that follow the spherical geometry of the joint. This curvature allows the cables to achieve optimal leverage arms for generating clamping force while maintaining a compact profile that can pass through small incisions.
3Adaptability or versatility
If articulation mechanism is added to access surgical site, then access to restricted space is improved, but ease of operation worsens
Solution Approach 1:
The articulation control mechanisms are merged with the tool assembly structure itself. The articulation joint integrates the cable routing, linkage members, and pivoting mechanisms into a unified assembly that moves as a coordinated system, reducing the number of separate controls the surgeon must manage while achieving complex spatial repositioning.
Data Source
AI summary
A surgical grasper includes an articulation assembly configured to enable a tool assembly to pivot in a first plane and articulate in a second plane orthogonal to the first plane. The surgical grasper eliminates the center line pivot joint used in conventional articulation mechanism, which, in turn, enables use of thicker cable that provides greater clamping force of first and second jaws of the tool assembly.