Braided Steerable Medical Device Wire Integration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing intraluminal medical devices with electroactive polymers (EAP) face challenges in securely integrating and managing small, sensitive electrically-conductive wires, which are prone to damage due to electrostatic forces and are difficult to assemble using conventional methods.
Innovation Solution
The development of a steerable medical device featuring a braided structure that securely integrates electrically-conductive wires with a support member, combined with an ionic electroactive polymer actuator and electrodes, allows for improved steering control and positioning of the device within a body lumen.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional mechanical assembly techniques are used to integrate electrically-conductive wires into the catheter shaft, then the assembly process is simple and straightforward, but the wires are too small (around 25 microns or smaller) to be assembled effectively and are vulnerable to damage from electrostatic forces
Solution Approach 1:
The patent combines the support member and electrically-conductive wires into a single integrated braided structure. The wires are braided together with the support member to form a unified assembly that is then introduced into the catheter shaft as one unit, eliminating the need for separate assembly steps and reducing wire damage risk
Solution Approach 2:
The braided structure acts as an intermediary that protects the sensitive electrically-conductive wires during assembly and operation. The braiding process creates a protective framework that shields the thin wires from electrostatic forces and mechanical damage while maintaining their electrical functionality
2Ease of manufacture
If the catheter shaft wall is made thin to facilitate wire integration, then wire assembly becomes easier, but the shaft becomes more vulnerable to damage and less structurally sound
Solution Approach 1:
The support member and wires are merged into a braided assembly that provides structural reinforcement. This integrated structure maintains catheter shaft strength while creating sufficient internal space for wire integration without requiring thin walls
Solution Approach 2:
The braided structure combines the support member material with electrically-conductive wire material to create a composite assembly. This composite structure provides both mechanical strength for shaft integrity and electrical conductivity for wire functionality, eliminating the need to compromise wall thickness
3Ease of operation
If the catheter is made flexible to navigate bodily passages, then the device can be inserted and guided through lumens, but directional control and steering become more difficult
Solution Approach 1:
The catheter incorporates a bendable portion with electroactive polymer actuators that can dynamically change shape in response to electrical signals. This dynamic capability allows the flexible catheter to be actively steered by controlling the bending of specific segments, providing directional control without requiring complex mechanical steering mechanisms
Solution Approach 2:
The patent replaces traditional mechanical steering mechanisms with an electroactive polymer-based actuation system. Electrical signals applied to the EAP elements control the bending and shaping of the catheter, substituting complex mechanical linkages with a simpler electrical control system that maintains flexibility while enabling precise steering
4Adaptability or versatility
If electroactive polymers are used to enable shape changing and steering, then the catheter can be selectively bent and positioned, but the structure becomes more complex and difficult to manufacture
Solution Approach 1:
The catheter is divided into distinct segments including a flexible portion and a bendable portion with separate electroactive polymer actuators. This segmentation allows each section to have optimized functionality while simplifying the overall manufacturing process by enabling modular assembly of the EAP components
Solution Approach 2:
The electroactive polymer elements serve multiple functions: they provide shape changing capability for steering, enable positioning control, and can potentially adapt to different anatomical configurations. This multi-functionality reduces the need for separate mechanical components, simplifying the overall catheter structure despite the advanced actuation mechanism
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
This solution enhances the stability and maneuverability of the medical device, reducing wire damage and facilitating more efficient and controlled movement within the body, thereby improving the accuracy and effectiveness of medical procedures.
Implementation Method 1
at least one ionic electroactive polymer actuator, the actuator including at least one polymer electrolyte layer secured adjacent to the distal end of the elongate, flexible inner member and defining an exterior surface, a plurality of electrodes circumferentially distributed about the exterior surface of at least one polymer electrolyte layer, and wherein at least one of the plurality of electrically-conductive wires, at the distal end thereof, is electrically connected to one of the electrodes, and, the at least one polymer electrolyte layer is configured to deform asymmetrically in response to the application of an electrical signal through at least one of the plurality of electrically-conductive wires to at least one of the plurality of electrodes
Data Source
AI summary
An elongate, flexible, medical device having distal and proximal ends, including an inner member having a proximal and distal end, a support member extending around the inner member between the proximal and distal end, a plurality of electrically-conductive wires, each braided with the support member having a proximal and distal end, an outer member surrounding the inner member, the support member, and the plurality of electrically-conductive wires and an actuator including a polymer electrolyte layer secured adjacent to the distal end of the elongate, flexible inner member and defining an exterior surface, electrodes distributed about the exterior of the polymer electrolyte layer. The distal end of one of the electrically-conductive wires is electrically connected to one of the electrodes. The polymer electrolyte layer is configured to deform asymmetrically in response to the application of an electrical signal through the plurality of electrically-conductive wires to the plurality of electrodes.