Steerable Instrument Bowden Cable Length Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing steerable instruments for endoscopic and invasive applications face issues with uncontrollable tip deflection when navigating through curved channels, leading to potential damage or misalignment, and require complex assembly processes with high manufacturing costs and variability.
Innovation Solution
A steerable instrument design featuring a Bowden cable arrangement with pre-assembled, integrally manufactured parts from tubes using 3D printing or plating techniques, minimizing assembly effort and parts, and employing laser cutting for precise alignment, reducing manufacturing costs and improving accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional steering cables are used in steerable instruments, then the instrument can be steered through curved channels, but the tip deflection becomes uncontrollable leading to potential damage or misalignment
Solution Approach 1:
The instrument shaft is divided into multiple rigid segments connected by flexible joints, allowing controlled bending at specific locations while maintaining stability of individual segments. This segmentation enables precise tip positioning without the uncontrollable deflection issues of conventional cable-based steerable designs.
Solution Approach 2:
The instrument employs dynamic control of segment orientations through articulated joints, allowing the operator to adjust the bending configuration in real-time. This dynamic capability provides fine control over tip deflection while navigating curved channels, preventing both excessive bending and misalignment.
2Manufacturing precision
If complex assembly processes are used to manufacture steerable instruments, then precise alignment can be achieved, but manufacturing costs increase and variability is reduced
Solution Approach 1:
Multiple components are merged into integrated assemblies where segments, joints, and steering mechanisms are pre-assembled as unified modules. This merging reduces the number of separate assembly steps while maintaining alignment accuracy through precision-engineered integrated components.
Solution Approach 2:
Critical alignment features and pre-bent configurations are prepared in advance during manufacturing. Segments are pre-aligned and pre-assembled with precise geometric relationships established before final instrument assembly, reducing the need for complex post-assembly adjustments and improving manufacturing efficiency.
Data Source
AI summary
A cylindrical instrument has a first tube (1601; 1619), a second tube (1620) surrounding the first tube (1601; 1619), and a third tube (1602; 1621) surrounding the second tube (1620). The instrument has a deflectable tip section (1613), a steering section (1618), a flexible body section (1615) between the tip section (1613) and the steering section (1618), a length compensation section (1617), and one or more steering wires (16(i)) extending from the steering section (1618) to the tip section (1613) such that the tip section (1613) can be deflected by moving the one or more steering wires (16(i)) in a longitudinal direction of the cylindrical instrument. The cylindrical instrument has a Bowden cable arrangement for each steering wire (16(i)) inside the length compensation section (1617), each Bowden cable arrangement has a steering wire (16(i)) surrounded by steering wire guiding portions. The steering wires (16(i)) and the steering wire guiding portions are portions of the first tube (1619), the second tube (1620), or the third tube (1621).