Like its cousins radar and sonar, lidar (light detection and ranging), works by broadcasting electromagnetic waves towards a target and then building up a picture from the reflection.

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These include GPS, stereo cameras, radar and Light Detection and Ranging (LIDAR) laser tracking.

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The approach du jour for most researchers is something known as Light Detection and Ranging ( LIDAR) -- a laser-based technology capable of creating precise maps over relatively large areas.

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