The light body of PeP just follows the person. To compare this behaviour to the active behaviour, a following behaviour is also implemented in PeP+ and adjusted to fit the body of PeP+. The dynamic characteristics, the way of moving, match the algorithm of the active behaviour. Moreover, in this implementation of the following behaviour, the position of the light body is still completely determined by the sensor input at that moment; the light body just follows. In the active behaviour, the direct coupling between sensing and acting applies. Curiosity and expectation motivate the light body to explore the person and the environment. The light body is more active than in the following behaviour. In the following behaviour, the light body is sensitive at all sides all the time and follows the person one-to-one. Exploratory movements are animated, and by these actions the light body does not actually explore. The design notions are more thoroughly implemented in the active behaviour, and it connects more strongly to the theoretical outline and examples than the following behaviour.
Besides the following and active behaviour, PeP+ can show a third behaviour, namely random behaviour. The random behaviour functions as control condition in the experiment. The random behaviour completely relies on the algorithm of the active behaviour, but the sensor input is generated randomly. The activity of the light body is random, and thus PeP+ does not sense the person in this behaviour.