One-minute videos · 3D perception

LiDAR Explained

Short, accurate explainers on LiDAR and 3D perception. Each video takes about a minute and assumes no background. I'm a LiDAR perception engineer with a PhD in AI, and I've spent years building systems that turn laser measurements into an understanding of the world.

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Explainer 01

What is LiDAR and how does it work?

LiDAR (Light Detection and Ranging) is a sensor that measures distance with light. It fires short laser pulses, up to millions every second, and times how long each one takes to bounce back. Light travels about 30 cm every nanosecond, so the round-trip time, multiplied by the speed of light and halved, gives the distance. Millions of these measurements build a 3D point cloud of everything around the sensor, in darkness as well as daylight. LiDAR is used in self-driving cars and robots, and to map forests, coastlines and cities.

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Explainer 02

LiDAR vs camera: what's the difference?

Cameras see the world; LiDAR measures it. LiDAR brings its own light, so it works in total darkness, and it measures distance directly, typically to within a few centimetres. A stereo camera has to infer depth, and its error grows with the square of the distance. FMCW LiDAR can also measure each point's speed using the Doppler effect. Cameras still win at colour, fine detail, reading signs and traffic lights, and cost. Radar copes best in heavy fog, rain and snow. That's why the best systems combine them.

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New videos are added regularly. Watch the full series on YouTube: https://www.youtube.com/@akandaashrafphd

Contact: akanda@akandaashraf.com