EM Sensor Location Using High-Density Field Maps
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electromagnetic navigation systems face challenges in accurately locating and orienting small-sized sensors, such as single-coil sensors, within a patient's body due to the time-consuming and laborious process of generating detailed EM field strength mappings, which is exacerbated by manufacturing variability and the need for precise measurements at numerous gridpoints.
Innovation Solution
The generation of a high-density EM field strength map, which includes finer gridpoint resolution, is achieved by combining measured EM field strengths with calculated strengths based on geometric configurations of antennas, allowing for accurate sensor location and orientation without the need for extensive measurements at every gridpoint, thereby reducing the burden of map generation and accommodating smaller sensors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple geometrically diverse EM fields are generated to enable accurate location of small-sized sensors, then measurement precision is improved, but the time required for map generation increases significantly
Solution Approach 1:
The patent divides the EM field generation process into two independent parts: (1) generating a low-density map by measuring EM field strength at a limited number of gridpoints, and (2) generating a high-density map by calculating EM field strength at many gridpoints using geometric configurations of antennas. This segmentation allows the system to achieve high measurement precision without the time cost of measuring at every high-density gridpoint.
Solution Approach 2:
The patent introduces calculated EM field strength values as an intermediary between the measured low-density map and the final high-density map. The calculated values, derived from geometric configurations of antennas, serve as a mediator that fills in the gaps between measured points, enabling the system to achieve high-density map resolution without performing time-consuming measurements at all locations.
2Measurement precision
If precise measurements are taken at many gridpoints to improve location accuracy, then measurement precision is improved, but device complexity increases
Solution Approach 1:
The patent segments the map generation task into measurement-based components (low-density map) and calculation-based components (high-density map). This segmentation reduces device complexity by avoiding the need for a complex measurement system at every gridpoint while still achieving high precision through the combination of measured and calculated data.
Solution Approach 2:
The patent creates a high-density map by copying and interpolating the low-density measured data points across the entire EM volume using geometric calculations. Instead of physically measuring at every location, the system generates a computational copy of the EM field distribution, reducing the complexity of the measurement apparatus while maintaining high precision.
3Measurement precision
If a high-density map with many gridpoints is generated, then measurement precision is improved, but loss of time increases
Solution Approach 1:
The patent segments the time-consuming measurement process into two phases: a quick low-density measurement phase and a faster calculation phase. By segmenting the work this way, the system achieves high-density map resolution without the time penalty of measuring at every high-density gridpoint.
Solution Approach 2:
The patent generates a high-density map by computationally copying the low-density measured data across the entire EM volume using geometric configurations of antennas. This copying approach is much faster than performing physical measurements at every location, significantly reducing the time required to generate a high-density map while maintaining high measurement precision.
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 approach enables efficient and accurate identification of sensor location and orientation within the patient's body, minimizing the time and cost associated with map generation while allowing the use of small-sized sensors in electromagnetic navigation procedures.
Implementation Method 1
an antenna assembly, the EM sensor, a processor, and a memory. The antenna assembly is configured to radiate an EM field within the EM volume
Implementation Method 2
receives, from a measurement device, a measured EM field strength at each gridpoint of a first set of gridpoints of the EM volume
Data Source
AI summary
Systems and methods for identifying a location and/or an orientation of an electromagnetic (EM) sensor navigated within an EM volume are provided. Calculated EM field strengths at each gridpoint of a second set of gridpoints of the EM volume are retrieved from a memory. An EM field is generated by way of an antenna assembly. A measured EM field strength is received from the EM sensor. A first gridpoint among a first set of gridpoints of the EM volume is identified based on the measured EM field strength and a high density (HD) map. The location and/or the orientation of the EM sensor is identified based on the HD map, using the first gridpoint as an initial condition, with the second set of gridpoints also including the first set of gridpoints.