Abstract Non-line-of-sight (NLOS) imaging is a rapidly growing field seeking to form images of objects outside the field of view, with potential applications in autonomous navigation, reconnaissance, and even medical imaging. The critical challenge of NLOS imaging is that diffuse reflections scatter light in all directions, resulting in weak signals and a loss of directional information. To address this problem, we propose a method for seeing around corners that derives angular resolution from vertical edges and longitudinal resolution from the temporal response to a pulsed light source. We introduce an acquisition strategy, scene response model, and reconstruction algorithm that enable the formation of 2.5-dimensional representations—a plan view plus heights—and a 180∘field of view for large-scale scenes. Our experiments demonstrate accurate reconstructions of hidden rooms up to 3 meters in each dimension despite a small scan aperture (1.5-centimeter radius) and only 45 measurement locations. 
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                            Source Seeking by Dynamic Source Location Estimation
                        
                    
    
            This paper focuses on the problem of multi-robot source-seeking, where a group of mobile sensors localizes and moves close to a single source using only local measurements. Drawing inspiration from the optimal sensor placement research, we develop an algorithm that estimates the source location while approaches the source following gradient descent steps on a loss function defined on the Fisher information. We show that exploiting Fisher information gives a higher chance of obtaining an accurate source location estimate and naturally leads the sensors to the source. Our numerical experiments demonstrate the advantages of our algorithm, including faster convergence to the source than other algorithms, flexibility in the choice of the loss function, and robustness to measurement modeling errors. Moreover, the performance improves as the number of sensors increases, showing the advantage of using multi-robots in our source-seeking algorithm. We also implement physical experiments to test the algorithm on small ground vehicles with light sensors, demonstrating success in seeking a moving light source. 
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                            - Award ID(s):
- 2003111
- PAR ID:
- 10379018
- Date Published:
- Journal Name:
- 2021 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)
- Page Range / eLocation ID:
- 2598 to 2605
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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