A Practical Validation of Uncooled Thermal Imagers for Small RPAS
Abstract
:1. Introduction
Previous Work
2. Materials and Methods
2.1. RPAS Airframes and Cameras
2.2. Blackbody Indoor Camera Validation
2.2.1. Thermal Radiation
2.2.2. Indoor Camera Validation—Blackbody Radiator
2.3. Outdoor Field Trial
2.3.1. Study Site Set-up
2.3.2. RPAS TIRI Acquisition
3. Results
3.1. Indoor Blackbody Validation
3.2. Outdoor Field Trial
Environmental Conditions
3.3. TIRI
3.3.1. Brightness Temperature
3.3.2. InfraGold Panel
3.3.3. Concrete Patio Stone Target
3.3.4. Grass and Soil
4. Discussion
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Appendix A
Camera | Distance (m) | Mean Blackbody Temp. (+/−0.4 °C) | Mean Measured Temp. (°C) | Stdev. (°C) |
---|---|---|---|---|
M2EA | 2 | 5 | 1.87 | 0.13 |
M2EA | 2 | 10 | 7.77 | 0.12 |
M2EA | 2 | 15 | 13.57 | 0.11 |
M2EA | 2 | 20 | 19.10 | 0.10 |
M2EA | 2 | 25 | 24.37 | 0.11 |
M2EA | 2 | 30 | 30.03 | 0.10 |
M2EA | 2 | 35 | 35.63 | 0.11 |
M2EA | 2 | 40 | 41.20 | 0.10 |
M2EA | 4 | 5 | 3.70 | 0.16 |
M2EA | 4 | 10 | 8.90 | 0.15 |
M2EA | 4 | 15 | 13.77 | 0.10 |
M2EA | 4 | 20 | 18.35 | 0.10 |
M2EA | 4 | 25 | 24.40 | 0.11 |
M2EA | 4 | 30 | 29.80 | 0.12 |
M2EA | 4 | 35 | 34.77 | 0.13 |
M2EA | 4 | 40 | 39.97 | 0.13 |
XT-R | 2 | 5 | 3.23 | 0.11 |
XT-R | 2 | 10 | 9.83 | 0.09 |
XT-R | 2 | 15 | 13.27 | 0.09 |
XT-R | 2 | 20 | 18.93 | 0.07 |
XT-R | 2 | 25 | 23.33 | 0.08 |
XT-R | 2 | 30 | 30.53 | 0.07 |
XT-R | 2 | 35 | 33.20 | 0.09 |
XT-R | 2 | 40 | 39.60 | 0.08 |
XT-R | 4 | 5 | 3.13 | 0.10 |
XT-R | 4 | 10 | 8.97 | 0.10 |
XT-R | 4 | 15 | 15.43 | 0.07 |
XT-R | 4 | 20 | 18.17 | 0.08 |
XT-R | 4 | 25 | 23.80 | 0.06 |
XT-R | 4 | 30 | 30.00 | 0.06 |
XT-R | 4 | 35 | 34.13 | 0.07 |
XT-R | 4 | 40 | 37.13 | 0.08 |
XT2 | 2 | 5 | 4.23 | 0.11 |
XT2 | 2 | 10 | 8.87 | 0.10 |
XT2 | 2 | 15 | 14.80 | 0.09 |
XT2 | 2 | 20 | 20.57 | 0.10 |
XT2 | 2 | 25 | 25.43 | 0.08 |
XT2 | 2 | 30 | 29.17 | 0.08 |
XT2 | 2 | 35 | 35.43 | 0.08 |
XT2 | 2 | 40 | 39.80 | 0.08 |
XT2 | 4 | 5 | 4.23 | 0.12 |
XT2 | 4 | 10 | 9.03 | 0.10 |
XT2 | 4 | 15 | 14.90 | 0.10 |
XT2 | 4 | 20 | 19.90 | 0.08 |
XT2 | 4 | 25 | 25.07 | 0.09 |
XT2 | 4 | 30 | 30.43 | 0.09 |
XT2 | 4 | 35 | 34.57 | 0.08 |
XT2 | 4 | 40 | 40.07 | 0.10 |
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RPAS | Take-Off Weight (kg) | Max. Take-Off Weight (Kg) | Max. Flight Time (min.) | Dimensions L × W × H (mm) | ~Cost (USD) | Year of Launch |
---|---|---|---|---|---|---|
M2EA | 0.909 * | 1.10 | 31 | 322 × 242 × 125 | 7200 | 2021 |
M600P ** | 9.5 | 21.0 | 38 | 1668 × 1518 × 727 | 9200 | 2016 |
M300 | 6.3 | 9.0 | 55 | 810 × 670 × 430 | 12,000 | 2020 |
Camera | Weight (g) | Range (μm) | Resolution (pixels) | FOV (°) | Pixel Pitch (µm) | Visual Camera | ~Cost (USD) | Year of Launch |
---|---|---|---|---|---|---|---|---|
M2EA | 639 | 8–14 | 640 × 512 | 46.2 | 12 | Y | Incl. | 2021 |
XT-R | 270 | 7.5–13.5 | 640 × 512 | 45° × 37° | 17 | N | 12,000 | 2016 |
XT2 | 588 | 7.5–13.5 | 640 × 512 | 45° × 37° | 17 | Y | 12,000 | 2018 |
Camera | Dist. (m) | Best Fit Equation | R2 | RMSE (°C) | 95% CI Slope | Bias (°C) | Mean Diff. (°C) | SD (°C) |
---|---|---|---|---|---|---|---|---|
M2EA | 2 | 1.117X − 3.451 | 0.9998 | 0.18 | 1.104X − 1.131 | −0.81 | 0.29 | 0.11 |
M2EA | 4 | 1.041X − 1.723 | 0.9993 | 0.36 | 1.014X − 1.068 | −0.80 | 0.18 | 0.13 |
XT-R | 2 | 1.018X − 1.415 | 0.9952 | 0.94 | 0.947X − 1.089 | −1.00 | 0.26 | 0.09 |
XT-R | 4 | 0.984X − 0.788 | 0.9926 | 1.12 | 0.899X − 1.069 | −1.15 | 0.29 | 0.08 |
XT2 | 2 | 1.023X − 0.736 | 0.9978 | 0.63 | 0.975X − 1.071 | −0.21 | 0.13 | 0.09 |
XT2 | 4 | 1.024X − 0.775 | 0.9992 | 0.39 | 0.995X − 1.054 | −0.23 | 0.08 | 0.10 |
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Leblanc, G.; Kalacska, M.; Arroyo-Mora, J.P.; Lucanus, O.; Todd, A. A Practical Validation of Uncooled Thermal Imagers for Small RPAS. Drones 2021, 5, 132. https://doi.org/10.3390/drones5040132
Leblanc G, Kalacska M, Arroyo-Mora JP, Lucanus O, Todd A. A Practical Validation of Uncooled Thermal Imagers for Small RPAS. Drones. 2021; 5(4):132. https://doi.org/10.3390/drones5040132
Chicago/Turabian StyleLeblanc, George, Margaret Kalacska, J. Pablo Arroyo-Mora, Oliver Lucanus, and Andrew Todd. 2021. "A Practical Validation of Uncooled Thermal Imagers for Small RPAS" Drones 5, no. 4: 132. https://doi.org/10.3390/drones5040132