Flexible Wrist Element for Surgical Force Transmission
Solution Overview
Problem
Existing mechanisms for transmitting mechanical force around corners and bends, such as in surgical environments, are inefficient due to high drag, complexity, or bulkiness, and fail to effectively combine axial and rotary movements.
Innovation Solution
A flexible wrist-type element with an angularly moveable hub housing and a rotatable end effector driven via a drive train incorporating universal-type joints, allowing for the transmission of axial and rotational forces through a push-pull-rotate mechanism with low-friction components and adjustable guide elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If push-pull cables are used to transmit mechanical force around corners and bends, then the mechanism can achieve flexibility and reach difficult-to-access areas, but the mechanism suffers from high drag and bending forces that reduce efficiency
Solution Approach 1:
The patent replaces traditional flexible push-pull cable mechanisms with a rigid robotic arm system that uses articulated joints and actuators to achieve flexibility. This substitution eliminates the high drag and bending forces inherent in flexible cables while maintaining the ability to reach difficult-to-access surgical sites through controlled articulation of the robotic segments.
Solution Approach 2:
The robotic system is divided into multiple articulated segments or links that can independently move relative to each other through joints. This segmentation allows the system to navigate around corners and bends by coordinating the movement of individual segments, replacing the continuous flexible cable with discrete rigid components that transmit force more efficiently.
2Adaptability or versatility
If cable-pulley mechanisms are used to transmit mechanical force around bends, then the mechanism can achieve rotational movement, but the mechanism becomes complex and feeble
Solution Approach 1:
The patent replaces complex cable-pulley rotational mechanisms with direct-drive or actuated joint systems in the robotic arm. Each joint is equipped with its own actuator (such as a motor) that directly produces rotational movement, eliminating the need for intermediate pulleys and cables while reducing overall system complexity and increasing strength.
Solution Approach 2:
The robotic system uses dynamically controllable joints with integrated actuators that can independently adjust their position and movement characteristics. This dynamic control replaces the static, mechanically coupled cable-pulley system with an actively controlled system that achieves rotational movement through coordinated actuation, simplifying the mechanical structure while maintaining versatility.
3Power
If hydraulic mechanisms are used to transmit mechanical force around bends, then the mechanism can achieve powerful actuation, but the mechanism becomes bulky and limited by hose travel
Solution Approach 1:
The patent replaces bulky hydraulic mechanisms with compact electric or pneumatic actuators integrated directly into each robotic joint. This substitution maintains the required actuation power while dramatically reducing the volume of the mechanism and eliminating the need for extensive hydraulic hoses, allowing for more compact and flexible robotic arm design.
Solution Approach 2:
The hydraulic system is replaced by distributing compact actuators to each segment of the robotic arm. Instead of using a centralized hydraulic power source requiring long hoses to reach each joint, each segment has its own integrated actuator, reducing overall system volume and eliminating hose travel limitations while maintaining powerful actuation capability.
4Adaptability or versatility
If traditional mechanisms are used to transmit both axial and rotary movements, then the mechanism can perform multiple functions, but the mechanism fails to effectively combine these movements
Solution Approach 1:
Each robotic joint is designed as a universal articulation point capable of performing both axial (push-pull) and rotary movements through a single integrated structure. The joints can operate in multiple degrees of freedom, allowing the system to effectively combine different types of movements without requiring separate mechanisms, thereby improving productivity and operational effectiveness.
Solution Approach 2:
The robotic system uses dynamically controllable joints that can switch between axial and rotary movement modes as needed. Each joint is actuated by independent actuators that can produce different types of motion depending on the operational requirements, allowing for effective combination of axial and rotary movements through coordinated dynamic control rather than fixed mechanical configurations.
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 precise and efficient transmission of mechanical forces around corners and bends, improving mechanical efficiency and enabling applications in surgical and other fields where complex movements are required.
Implementation Method 1
a rotatable and operable end effector driven via a drive train having one or more flexible couplings, such as universal-type joints
Data Source
AI summary
A flexible wrist-type element and methods of operation thereof, including variations having an angularly moveable hub housing a rotatable and operable end effector driven via a drive train having one or more universal-type joints and/or other flexible couplings moveable via an input mechanism within a housing.