Actograph. Actographs are a family of devices used to measure activity of an animal. Actographs come in many shapes and sizes, typically in the form of a cage. Movements within are recorded using, for instance, mechanical, photoelectric, ultrasonic, acoustical, and video devices. A activity wheel is considered one type of actograph, but generally an actograph measures activity of an animal within its home environment. The actograph pictured here was developed to measure behavior of a crayfish. When the crayfish moves its activity is sensed by a paddle. The more the animal moves the more the paddle moves.