Infrared: Snake Hunt

Landmines are dangerous explosives hidden in the ground in war zones, which are designed to blow up when stepped on. They can stay in the ground for years, or even decades, then explode the next time someone puts their foot in the wrong place.

Teenager Harshwardhan Zala came up with his clever idea after reading about how dangerous it is for soldiers to defuse landmines by hand. Defusing means removing a wire called the fuse from the mine so it can no longer explode. He thought that it was time for a solution that wouldn’t put anyone else’s life in danger.

First, Harshwardhan thought about making a robot to defuse the landmines, but quickly realised that the robot would be destroyed when its own weight caused the mine to explode. His solution was to adapt a small, remote-controlled aircraft called a drone. Harshwardhan’s drone can hover about 60 centimetres above the ground, and uses special sensors to find any landmines hidden beneath the soil.

The sensors work by measuring infrared light – a type of light that is invisible to the human eye. The warmer an object is, the more infrared light it gives off, so an infrared sensor can be used to find things that are hotter or colder than their surroundings.

This is important for Harshwardhan’s invention because the metal landmines absorb more of the Sun’s heat than the surrounding soil, making the mines warmer than the earth around them. So although we can’t see the landmines with our eyes, the drone finds them by looking for places where the temperature of the soil suddenly changes. Once the drone has found a landmine, the plan is to safely carry out a controlled explosion using a small 50-gram bomb.

The Indian government is so impressed with Harshwardhan’s idea that it has given him almost £600,000 to develop it further. Apparently, his design is better than anything the Indian Armed Forces currently uses to clear landmines – so well done, Harshwardhan!

Watch Infrared: Snake Hunt to find out more about how an animal uses infrared light to help it find its prey.