Coded Aperture Seeker Using SWIR Imaging for Inertial Drift Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current imaging systems in guided munitions face challenges in navigational accuracy, especially in GPS-denied environments, and require smaller package sizes with increased capabilities to correct inertial measurement drift and navigate effectively.
Innovation Solution
A guided munition system equipped with coded aperture imaging devices, including a sensor sensitive to short-wave infrared wavelengths and a spatial light modulator, which can change its pattern for situational adaptability, is used to collect and process images of celestial bodies, horizon, and terrain for navigation, enabling the determination of direction, orientation, and rotational position of the munition.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional imaging systems are used in guided munitions, then the package size can be smaller, but navigational accuracy and capability to correct inertial measurement drift are insufficient
Solution Approach 1:
The imaging system is divided into multiple coded aperture imaging devices, each with specialized sensors (e.g., SWIR-sensitive sensors) positioned at different locations on the munition. This segmentation allows each device to capture specific navigational information (celestial bodies, horizon, terrain) while maintaining a compact overall package size.
Solution Approach 2:
The coded aperture imaging devices are designed to perform multiple navigational functions simultaneously - celestial navigation, horizon sensing, and terrain mapping - using the same basic hardware platform. This multi-functionality increases navigational capability without proportionally increasing package size.
2Adaptability or versatility
If GPS-denied navigation is implemented, then navigation capability in denied environments is improved, but measurement drift correction becomes more difficult
Solution Approach 1:
The system continuously captures images of celestial bodies, horizon, and terrain, processes this visual information to determine munition orientation and position, and feeds this data back to correct inertial measurement drift in real-time, enabling sustained accurate navigation without GPS.
Solution Approach 2:
The patent replaces reliance on GPS satellite signals with optical imaging-based navigation using coded aperture devices. This substitution enables navigation in GPS-denied environments by using visual landmarks (celestial bodies, horizon, terrain) instead of satellite-based positioning.
3Area of stationary object
If coded aperture imaging devices are mounted on the munition body, then field of view and navigational data are improved, but device complexity increases
Solution Approach 1:
Multiple coded aperture imaging devices are merged into a single integrated navigational system that shares processing resources and control electronics. This combining approach increases the effective field of view and navigational data availability while managing system complexity through shared architecture.
Solution Approach 2:
The coded aperture mask introduces an additional dimensional layer to the imaging system, enabling super-resolution and enhanced field of view without proportionally increasing physical sensor size. This dimensional addition improves navigational data quality while controlling hardware complexity.
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 solution enhances navigational accuracy and adaptability by providing a larger field of view, reducing measurement errors, and allowing multiple sensors to be strategically placed on a munition for combined data, effectively navigating in GPS-denied environments and improving inertial navigation correction.
Implementation Method 1
The coded aperture can include a spatial light modulator (SLM) configured to change the pattern in the mask for situational adaptability
Implementation Method 2
The sensor can include a focal plane array (FPA). The FPA can be sensitive to short-wave infrared (SWIR) wavelengths
Data Source
AI summary
A guided munition system includes a munition body including at least one fluid dynamic control for changing course of the munition body in flight. A seeker onboard the munition body is operatively connected to control the at least one fluid dynamic control. The seeker includes a coded aperture imaging device facing outward from the munition body for image based control for guiding the munition body in flight.