Laser Awareness Sensor Using Delay Map Plane Fit
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional laser strike detection systems on aircraft are limited in their ability to detect laser strikes that do not directly impinge on optical sensors, often missing strikes and providing insufficient information on the origin of the laser beam, making it impractical to cover an entire aircraft and failing to accurately determine the emission direction of the laser.
Innovation Solution
A laser-strike detection system utilizing an imaging sensor and computing device to generate image frames of a field of view, computing a delay map based on the time-of-arrival of scattered laser light, and converting it into a path-length variation map to determine the direction of the laser beam emission, allowing for accurate identification of the laser's origin.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional optical sensors are used to detect laser strikes, then direct impingement strikes can be detected, but strikes that miss the sensor location are missed and coverage is insufficient
Solution Approach 1:
The aircraft surface is divided into multiple regions with distributed optical sensors, each responsible for detecting laser strikes in its local area. This segmentation allows comprehensive coverage without requiring a single complex sensor system, resolving the contradiction between detection coverage and system complexity.
Solution Approach 2:
Each optical sensor is designed to perform multiple functions: detecting direct laser impingement, measuring time-of-arrival, and contributing to delay map construction. This multi-functionality allows a single sensor type to address both local detection and global localization, improving reliability without increasing device complexity.
2Loss of information
If conventional optical sensors are used to detect laser strikes, then detection capability is provided, but origin direction information is insufficient and general only
Solution Approach 1:
The system uses feedback from multiple optical sensors measuring time-of-arrival of scattered laser light to continuously refine the delay map and improve laser origin direction estimation. This feedback mechanism transforms general detection data into precise directional information, reducing information loss while maintaining measurement precision.
Solution Approach 2:
The system transitions from two-dimensional sensor placement to three-dimensional delay map construction by incorporating time-of-arrival measurements as a temporal dimension. This additional dimension enables precise localization of laser origin direction without requiring more sensors, addressing the information loss problem while maintaining measurement accuracy.
3Reliability
If optical sensors are distributed to cover the entire aircraft, then comprehensive detection is achieved, but system complexity and cost become impractical
Solution Approach 1:
The aircraft surface is divided into multiple regions with distributed optical sensors, each responsible for detecting laser strikes in its local area. This segmentation allows comprehensive coverage without requiring a single complex sensor system, resolving the contradiction between detection coverage and system complexity.
Solution Approach 2:
A central computing device acts as an intermediary that receives time-of-arrival data from multiple simple optical sensors, constructs the delay map, and determines laser origin direction. This intermediary approach allows the system to achieve comprehensive detection coverage while keeping individual sensor units simple and the overall system manageable.
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
Enables comprehensive detection of laser strikes across the aircraft and precise determination of the laser beam's emission direction, improving the ability to detect and respond to potential threats by providing accurate directional information.
Implementation Method 1
The optical system is configured to collect, from a field-of-view (FOV) of the optical system, light that is reflected or scattered from a platform
Implementation Method 2
The optical system is configured to collect, from a field-of-view (FOV) of the optical system, light that is reflected or scattered from a platform
Implementation Method 3
The computing device computes, based upon the image frames, a time-of-arrival of scattered laser light at the imaging sensor from various points on the portion of the platform in the FOV
Data Source
AI summary
A laser-strike detection system includes an imaging sensor mounted on a platform, and a computing device. The imaging sensor outputs image frames that are each representative of a portion of the platform at a different time, during which a laser may be striking the platform. The computing device receives the image frames, and computes a delay map that indicates time-of-arrival delays of the laser beam at points on the portion of the platform. The computing device converts the delay map to a path-length variation map by multiplying the delay map by the propagation speed of light. The computing device fits a plane to the path-length variation map constrained by a topological model of the platform. The computing device computes angular deflections in x- and y-directions based upon the fit, which angular deflections define a direction from the platform to an emitter of the laser beam.