Multi-Sensor Catheter for Six-Degree-of-Freedom Positioning
Solution Overview
Problem
Current catheters with single sensors can only determine the location of the distal end within five degrees-of-freedom, limiting their ability to accurately navigate and reposition during procedures like bronchoscopy without a separate locatable guide.
Innovation Solution
A flexible catheter design incorporating a first sensor at the distal end and a second sensor spaced a known distance apart, allowing determination of the distal end's position within six degrees-of-freedom, eliminating the need for a separate locatable guide and enabling continuous location tracking during procedures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single sensor is used in the catheter, then the device complexity is reduced, but the measurement precision of the catheter position is limited to five degrees-of-freedom
Solution Approach 1:
The catheter is segmented into multiple sensing zones with at least two sensors positioned at different locations along the catheter body. Each sensor independently detects position information, and the combination of readings from multiple sensors enables determination of all six degrees-of-freedom (three positional coordinates and three orientational angles), thereby achieving complete spatial localization without requiring a single complex sensor.
Solution Approach 2:
The patent transitions from single-point sensing to distributed multi-point sensing along the catheter length. By adding the spatial dimension of sensor distribution and utilizing the known separation distance between sensors, the system gains additional measurement capabilities that enable full six-degree-of-freedom position and orientation determination.
2Measurement precision
If multiple sensors are added to achieve six degrees-of-freedom positioning, then the measurement precision is improved, but the device complexity increases
Solution Approach 1:
The patent employs sensors that perform multiple functions: each sensor not only detects positional coordinates but also contributes to determining orientational angles when combined with readings from other sensors. The sensors are integrated into the catheter structure such that they serve both localization and orientation functions, reducing the need for separate sensing systems and thereby limiting the increase in device complexity.
Solution Approach 2:
The patent combines multiple sensing elements into a unified catheter system where the sensors are integrated along the catheter body. The known separation distance between sensors is utilized as a geometric reference, merging position and orientation measurement capabilities into a single coherent system that determines all six degrees-of-freedom without requiring separate positioning and orientation devices.
3Measurement precision
If sensors are added to the catheter wall, then the measurement precision is improved, but the wall thickness increases
Solution Approach 1:
The sensors are nested within the catheter wall structure rather than adding external layers. The sensing elements are embedded in the existing wall, utilizing the wall material itself as part of the sensor housing or mounting structure. This nesting approach allows integration of sensing functionality without proportionally increasing the overall wall thickness.
Solution Approach 2:
The patent implements sensors at specific localized positions along the catheter body rather than uniformly thickening the entire wall. The sensing elements are concentrated at discrete locations where they are most effective, allowing the catheter wall to maintain its baseline thickness in non-sensing regions while achieving precise localization capabilities at sensor positions.
4Measurement precision
If sensors are added to the catheter, then the measurement precision is improved, but the overall diameter of the catheter increases
Solution Approach 1:
The sensors are nested within the existing catheter wall structure, utilizing the wall thickness and internal space to accommodate sensing elements. This approach allows integration of multiple sensors without requiring a proportional increase in the outer catheter diameter, as the sensors are housed within the existing structural envelope rather than adding external bulk.
Solution Approach 2:
The patent employs thin-film or flexible sensor technologies that can be integrated into the catheter wall with minimal dimensional impact. These thin-film sensors require minimal space and can be deposited or bonded to the inner or outer surface of the catheter wall, achieving sensing functionality without significantly increasing the overall catheter diameter.
Data Source
AI summary
A flexible catheter includes an elongated body, a first monolithic wire, and a second monolithic wire. The first monolithic wire forms a first sensor that is disposed in the distal end portion of the elongated body. The first sensor is configured to detect the position of a distal end of the elongated body within anatomy of a patient. The second monolithic wire forms a second sensor that is disposed in the distal end portion of the elongated body a known distance from the first sensor. The first and second sensors are configured to determine the position of the distal end portion within six degrees-of-freedom. A method of manufacturing the flexible catheter is also provided.