If you're a scientist who studies wild penguins you have one, fairly large, problem: you're not a penguin.
A human going up to penguins in the wild could stress them out and change their behaviour. Then all you have is unhappy penguins and unreliable results.

To get around this predicament scientists have tried sending mini rovers – essentially fancy remote control cars – in to take the readings they need. And it seems to be working.
Scientists tagged 34 king penguins with external heart rate monitors that could be read by an antenna fixed to a rover. The next day they sent a rover (not dressed up as a baby penguin) into the group of penguins.
And it worked! The king penguins' heart rates increased less and returned to normal quicker than when compared to humans approaching them.
In the next experiment scientists dressed the rover up as a penguin chick and sent it to take readings from a group of emperor penguins.

Emperor penguins are shyer than most, but this trick seemed to work on them.The penguins allowed the dressed-up rover to get close enough to take the readings it needed. Some chicks and adults even made noises at the rover. And it was able to infiltrate a baby penguin huddle (as you can see above) without disturbing them.