TEAM PEREGRINE Chemical Agent Detection from Small Unmanned Aerial System Using Hyperspectral Sensor at the Office of the Secretary of Defense Rapid Reaction Technology Office (RRTO) THUNDERSTORM February 2015 Camp Shelby, MS
Objectives THUNDERSTORM 15-3 Focus Area: Explore emerging technologies for their technical applications and their potential to use a battery-powered Vertical Take-Off and Land (VTOL) Unmanned Aerial System (UAS) to support the detection and identification of chemical and/or biological Weapons of Mass Destruction (WMD). TEAM PEREGRINE: Integrate sUAS and Nano-Hyperspec ® Hyperspectral (HSI) Sensor Adapt sUAS Flight Characteristics to Accommodate HSI Data Collection Demonstrate Chemical Agents Detection Through Hyperspectral Data Analysis
Camp Shelby, Hattiesburg Mississippi Combined Arms Collective Training Facility (CACTF) Data was collected on 24 February 2015 at approximately 1030hrs Location/Environment 23 FEB 50% 46/34 24 FEB 25FEB 40%100% 38/32 42/35 Weather CACTF
Simulant Chemical Target Material Methyl Salicylate (MES) Target Environment Urban environment of various building materials, structures and sizes. Dispersal Method: Placed on black plastic, clear plastic, soil and concrete Target Characteristics Standard US Army Chemical Simulant Complex organic ester naturally produced by many species of plants, particularly wintergreens
sUAS System Overview Hyperspectral Sensor Key Specifications: 640 spatial bands 270 spectral bands ~2.2nm spectral sampling interval 5nm spectral resolution (FWHM with 20-micron slit) 17mm lens (others available and switchable) 480GB storage capacity (~ 130 minutes at 100 fps) Connectivity: Gigabit Ethernet Size 3" x 3" x 4.72" (76.2mm x 76.2mm x mm) Weight: less than 1.6 lb. (0.72kg) Small Unmanned Aerial System Key Specifications: Hex Multicopter Frame 3DR Pixhawk Open-Source Flight Controller Fully Autonomous Flight Control and Mission Planning Endurance min with options for longer flights Data processed post-flight Weight: less than 8 lbs 640px 270 “Layers”
Planned Mission Flown Mission Mission Planning Autonomous Route 5-meter/second Speed 300 Feet Altitude Flight Duration 7 Minutes MES Target Information Provided Located within Polygon Dispersed on and near structures Flight Pattern Target Boundary Mission As Flown Nadir coverage from sensor Computer controlled (Autonomous) flight
Target Detection / Identification Detection 2 Detection 1 Detection 3
Data Processing Parameters Visible-Near Infrared (VNIR) ( nm) Hyperspectral (HSI) data was calibrated to spectral radiance and ortho-rectified Calibrated images were atmospherically corrected using a modified flat field technique Bad bands were removed from each image Target detection for the MES lab signature was performed using Matched Filter Spectral Angle Mapper Constrained Energy Minimization Adaptive Coherence Estimator Positive detections and false positives suppression used thresholds employing a weights of evidence model for the performance of all four algorithms Calibration factors for modified flat field correction
Lab spectrum for MES plotted in RED vs detected spectral signatures for MES in-scene Detection 1 depicts a much higher concentration of the MES chemical than Detection 2 Detection 3 depicts a higher concentration than Detection 2 but lower than Detection 1 Detection 2 Detection 1 Detection 3 Spectral Identification
Accomplishments sUAS Frame-Mounted Hyperspectral Sensor Collects Push Broom Imagery that enables Detailed Analytics of the Data Cube, such as target detection and identification Data Cube Analytics Enable Positive Identification of Target Simulant Material (Methyl salicylate) No “False Positive” Detections Within the Data Cube Identify Areas for Improvements in Optimal System sUAS, Sensor, Data Analytic Software Integration Real-Time Analysis and Reporting for Collected Data Autonomous Flight Control Able to Collect Actionable Data Despite Overcast Skies