Non-Linear Navigation Sensor Strain Relief for Flexible Catheters
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Inductive coils on flexible catheters experience strain, leading to kinking or breakage due to deflection, which affects the accuracy of position sensing.
Innovation Solution
A sensor assembly with inductive coils wound around a tubular member, providing strain relief through a support member that flexes to reshape the catheter's distal portion, using a tubular member to indirectly couple with the support member, allowing the coils to move relative to each other, and incorporating dual cables for additional strain relief.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If inductive coils are wrapped directly around a flexible catheter structure, then the catheter can be deflected to navigate, but the coil wiring experiences strain leading to kinking or breakage
Solution Approach 1:
The catheter is divided into modular sections with inductive coils mounted on separate tubular members that can move independently relative to the main catheter body, allowing deflection without transmitting strain to the coil wiring
Solution Approach 2:
Tubular members act as intermediary structures between the flexible catheter body and the inductive coils, absorbing mechanical strain and preventing direct transmission of stress to the coil wiring during catheter deflection
2Measurement precision
If inductive coils are fixed rigidly to maintain position accuracy, then measurement precision improves, but the catheter loses flexibility for navigation
Solution Approach 1:
The system transitions from rigid fixed mounting to dynamic mounting where tubular members can move relative to the catheter body, maintaining coil alignment and measurement precision while allowing catheter flexibility for navigation
Solution Approach 2:
The mounting system allows change in mechanical parameters (position, orientation) of the tubular members relative to the catheter body, enabling the catheter to adapt its shape while keeping the inductive coils properly aligned for accurate position sensing
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 strain on the inductive coils, preventing kinking and breakage while maintaining accurate position sensing during catheter navigation.
Implementation Method 1
A magnetic field can be sensed by positioning a conductive coil in the magnetic field and observing electrical current and/or voltage induced in the coil by a change in the magnetic field that is aligned with an axis of the conductive coil
Data Source
AI summary
The distal end of the catheter can be constructed to include one or more features to provide strain relief to wiring of multiple single axis sensors. In some examples, the multiple single axis sensors and associated wiring can be manufactured over a flexible tube that can be placed over a movable support member. In some examples, wiring can be wound an increased number of consecutive traverse turns on a distal and/or proximal side of a single axis sensor, and a shrink sleeve may be positioned over the traverse turns. In some examples a wire shield transition point can be positioned on a straight portion in a proximal direction to the distal portion of the catheter.