The Micro-Droid Machine was an invention created by Professor Farnsworth. It was created to allowed the Planet Express crew to go inside of Fry's body in an effort to stop worms which were attacking his body. The user would be scanned and a small capsule would come out of a hole, inside of which was the Micro-Droid. To control the micro-droids, the crew would use virtual reality net suits, similar to using the internet.
The machine is a parody of a gotcha machine or a kinder surprise egg.