Asked by: Rhys Abul, Southampton

Sending out sound waves and listening for their echo is a great way to detect obstacles in water – submarines can detect objects many kilometres away. But sound doesn’t travel nearly so well in air. Bats can only detect objects up to 20 metres away, falling to around two metres in poor conditions. Light is less affected by atmospheric conditions, which is why self-driving cars use LIDAR (‘light detection and ranging’), bouncing infrared laser light off objects in order to detect them.

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Authors

Dr Peter Bentley
Dr Peter Bentley

Dr Peter Bentley is a computer scientist and author who is based at University College London. He is the author of books including 10 Short Lessons in Artificial Intelligence and Robotics and Digital Biology: How nature is transforming our technology and our lives.

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