ABSTRACT
A behavior tree (BT) is a way to structure the switching between different tasks1 in an autonomous agent, such as a robot or a virtual entity in a computer game. An example of a BT performing a pick and place task can be seen in Figure 1.1(a). As will be explained, BTs are a very efficient way of creating complex systems that are both modular and reactive. These properties are crucial in many applications, which has led to the spread of BT from computer game programming to many branches of AI and robotics.
