Robots were first glued to the backs of five red-eared slider turtles. The robots comprised a processor, a frame that stuck out in front of the turtle’s head holding five red LEDs spaced apart, and a food-ejecting tube. They then had to ride their turtle through five checkpoints in a tank filled with water.
The turtles were first conditioned to associate a lit-up LED with food. The robot then simply guided it using the LEDs and fed it snacks as a reward for going in the right direction. Using this process, five robot-turtle pairs successfully completed the course, and each sped up with practice.