Photon-Efficient Scanning LiDAR System
Sensors
Photon-Efficient Scanning LiDAR System (GSC-TOPS-388)
Optimized Compressive Scanning for Enhanced Remote Sensing
Overview
Scanning LiDAR (Light Detection and Ranging) is an advanced remote sensing technology that uses laser pulses to create high-resolution, three-dimensional maps of surfaces. Traditional LiDAR systems often lack control over uniform scanning patterns, leading to inefficient or redundant information over uniform terrains like deserts and oceans, resulting in unnecessary power consumption and data storage challenges. Scanned data is compressed because much of the data is duplicative and can waste LiDAR resources such as photons, power, and detector capacity while also burdening data transfer, storage, and processing systems.
NASA engineers have developed a novel LiDAR approach utilizing compressive coded aperture scanning to address the inefficiencies of state-of-the-art LiDAR systems to build a 3D map of a selected area more efficiently. This method enhances photon efficiency by selectively omitting certain pixels during the scan and employing sophisticated algorithms to reconstruct the missing data, thereby optimizing resource utilization without compromising data quality.
The Technology
This new methodology selectively scans an area of interest and effectively pre-compresses the image data. Instead of using LiDAR resources to gather redundant data, only the necessary data is gathered and the redundancy can be used to fill in up-sampled data using intelligent completion algorithms. The system utilizes a unique LiDAR system to collect a pattern of specific points across a given area by modulating the incoming light, creating a pattern that can be decoded computationally to reconstruct a scene. By designing specific coding patterns, the system can strategically skip certain measurements during the scanning process to create an under-sampled image area.
The system reconstructs the under-sampled area to recreate an accurate representation of the original object or area being scanned. As a result, redundant data is prevented from being collected by reducing the number of required measurements and data condensed in post-collection to reduce power consumption. By selectively skipping certain pixels during the scan and using sophisticated recovery algorithms to reconstruct the omitted information, the system makes more efficient use of the available photons, thereby enhancing overall data collection.
This technology represents a significant advancement in LiDAR systems, offering a more useful method for data collection and processing and addresses the challenges of power consumption and data redundancy, allowing for more sustainable and effective remote sensing applications. This technology can offer advantages in applications such as mapping for construction, surveying, forestry, or farming as well as computer vision for vehicles or robotics.
Benefits
- Enhanced Photon Efficiency: Optimizes the use of photons without compromising sensing quality.
- Reduced Power Consumption: Extends the operational range, efficiency, and time of LiDAR systems.
- Minimized Data Redundancy: Collects sparser datasets with less redundant information.
- Adaptive Scanning: Utilizes different sampling codes, optimizing data quality and resource allocation for diverse applications.
Applications
- Satellite Mapping: Enhances efficiency in Earth observation.
- Autonomous Navigation: Provides precise 3D mapping for vehicles and robots.
- Construction Surveying: Enables accurate site mapping.
- Environmental Monitoring: Assists in assessing natural hazards.
- Archaeology: Facilitates non-invasive site documentation.
- Forestry and Agriculture: Supports crop and forest management.
- Urban Planning: Aids in developing detailed city models.
- Augmented and Virtual Reality: Improves spatial mapping for immersive experiences.
- Atmospheric Studies: Measures atmospheric particles and structures.
- Space Exploration: Maps planetary surfaces for exploration.
Technology Details
Sensors
GSC-TOPS-388
GSC-18616-1
GSC-18580-1
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