Detection and tracking of moving objects hidden from view


The ability to detect motion and track a moving object hidden around a corner or behind a wall provides a crucial advantage when physically going around the obstacle is impossible or dangerous. Previous methods have demonstrated that it is possible to reconstruct the shape of an object hidden from view. However, these methods do not enable the tracking of movement in real time. We demonstrate a compact non-line-of-sight laser ranging technology that relies on the ability to send light around an obstacle using a scattering floor and then detect the return signal from a hidden object within only a few seconds of acquisition time. By detecting this signal with a single-photon avalanche diode (SPAD) camera, we follow the movement of an object located a metre away from the camera with centimetre precision. We discuss the possibility of applying this technology to a variety of real-life situations in the near future.

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Figure 1: Looking around a corner.
Figure 2: Retrieving a hidden object's position.
Figure 3: Experimental results for position retrieval of the hidden object.
Figure 4: Non-line-of-sight tracking of a moving target.


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We acknowledge support from the European Research Council under the European Union's Seventh Framework Programme (FP/2007-2013)/ERC GA 306559, the Engineering and Physical Sciences Research Council (EPSRC, UK, grants EP/M006514/1, EP/M01326X/1, EP/ K03197X/1), and ST Microelectronics, Imaging Division, Edinburgh, for their support in the manufacture of the Megaframe chip. The Megaframe project has been supported by the European Community within the Sixth Framework Programme IST FET Open. G.G. acknowledges the financial support of the Fonds de Recherche Nature et Technologies du Quebec (grant no. 173779).

Author information




D.F. and J.L. conceived the experiment. R.K.H. designed the CMOS SPAD pixel architecture. G.G.performed the experiment. F.T. developed the tracking algorithm. G.G. and F.T. analysed the data and drafted the manuscript. All authors discussed the data and contributed to the manuscript.

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Correspondence to Genevieve Gariepy or Daniele Faccio.

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The authors declare no competing financial interests.

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Gariepy, G., Tonolini, F., Henderson, R. et al. Detection and tracking of moving objects hidden from view. Nature Photon 10, 23–26 (2016).

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