IIT Bombay researchers show one way how animals find their way home

IIT Bombay researchers use robots to study homing behavior in animals, mimicking foraging and navigation with light-based cues.

Researchers at IIT Bombay are using robots to understand how animals find their way back home from unfamiliar places, a skill called homing.

Nitin Kumar, assistant professor at the Department of Physics at IIT Bombay, explained, “The primary goal of our research group is to understand the physics of active and living systems. We achieve this by performing experiments on centimetre-sized self-propelled programmable robots. In simple words, we model these robots to mimic the dynamics of living organisms, both at the individual and collective levels.”

Homing is crucial for many life-forms, from birds flying thousands of kilometres during migration to ants finding their way back to their colonies after foraging. Humans have even harnessed this ability to train homing pigeons to deliver messages over long distances.

Dr. Kumar’s team has now developed a robot that mimics foraging and homing behaviour. This robot is designed to move on its own and use light as a guide to return home. In a new study, they have reported some principles of homing based on their studies with the robot.

The foraging robot is programmed to move semi-randomly, like how animals might wander when looking for food. This type of movement is called active brownian (AB) motion. The robot’s direction changes frequently due to rotational diffusion, a mechanism that introduces a certain level of randomness to its path. When the robot needs to return home, it shifts to a different mode that doesn’t include randomness inputs.

The researchers shone a beam of light on the robot; the light’s intensity changed gradually. The robot was programmed to follow this gradient light to find its way back, mimicking the way some animals use the Sun or other environmental light sources to find their way.

“The homing motion is similar to the AB model, except the robot undergoes frequent course corrections whenever it deviates significantly from its intended homing direction, as expected in actual living organisms” Dr. Kumar said.