Stapler Beam Architecture for Flexible Wrist Actuation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Minimally invasive surgical techniques, such as laparoscopy, face challenges in maintaining the flexibility and efficiency of actuation components due to the strain caused by large yaw and pitch angles in telesurgically controlled stapling devices, leading to potential buckling and reduced force transmission.
Innovation Solution
A flexible actuation assembly with a pulling and pushing assembly, where the pulling assembly transmits tensile force and the pushing assembly transmits compressive force, is integrated within a wrist assembly that can yaw and pitch at large angles, using configurations like coiled springs and braided cables to maintain efficiency and prevent buckling, with inner links constraining the actuation mechanism to limit lateral movement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the wrist assembly yaws and pitches at large angles to enhance flexibility, then the adaptability of the surgical device is improved, but the actuation components experience increased strain and potential buckling
Solution Approach 1:
The actuation mechanism is divided into multiple segments including outer links, inner links, a pulling assembly, and a pushing assembly. This segmentation allows each component to handle specific forces and movements independently, reducing the strain on any single component while enabling large yaw and pitch angles.
Solution Approach 2:
The inner links are nested within the outer links, and the pulling and pushing assemblies are housed within the wrist structure. This nested configuration allows the actuation components to operate within the constrained space of the wrist assembly while maintaining structural integrity during large angular movements.
2Adaptability or versatility
If the actuation mechanism is compressed within the wrist to enable high degree of flexibility, then the wrist assembly compactness is improved, but buckling occurs and force transmission efficiency decreases
Solution Approach 1:
The outer links are designed with specific geometric features that provide lateral support to the inner links and actuation assemblies at critical locations. This local reinforcement prevents buckling without requiring the entire structure to be rigid, maintaining flexibility while ensuring force transmission efficiency.
Solution Approach 2:
The inner links act as intermediary components between the outer links and the pulling/pushing assemblies. They provide structural support and constraint to prevent lateral movement and buckling of the actuation mechanism, ensuring efficient force transmission while allowing the wrist to achieve large angular movements.
3Device complexity
If a single actuation component is used for both pushing and pulling, then the device complexity is reduced, but the component experiences buckling under compression
Solution Approach 1:
The pulling assembly and pushing assembly are combined into a single integrated actuation mechanism housed within the wrist assembly. This merging allows both tensile and compressive forces to be applied through a unified structure, reducing overall device complexity while maintaining component stability through the segmented design of inner and outer links.
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
Enables the surgical device to effectively apply both compressive and tensile forces for actuating end effectors at high yaw and pitch angles, enhancing the flexibility and efficiency of the wrist assembly while preventing buckling, thus improving the performance of minimally invasive surgical procedures.
Implementation Method 1
the pushing component includes a coiled spring
Implementation Method 2
the pulling component includes a braided cable
Data Source
AI summary
An end effector that can have an upper jaw and a lower jaw. A wrist can connect the end effector to an elongated shaft. A beam member can be arranged to translate within the upper and lower jaw. An actuation assembly can have a pushing assembly configured to transfer compressive force to the beam member and a pulling assembly configured to transfer tensile force to the beam member.