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5. Refine each behavior, 5 Designing a Reactive Implementation
6. Test each behavior independently,
7. Test with other behaviors,

and repeat the process as needed. A behavior table serves as a means of repre-
senting the component schemas and functions of the behavioral system. For
each behavior, it shows the releasers, the motor schemas, the percept, and
the perceptual schemas.
These steps emphasize the need to fully specify the ecological niche of the
robot in order to design useful behaviors. Since the idea of behaviors in the
Reactive Paradigm is derived from biology, it is not strange that the idea of
a robot being evolved to fit its environment should also be part and parcel
of the design process. Regardless of the implementation of the coordination
program , the control should rely on the world to inform the robot as to what
to do next, rather than rely on the program to remember and maintain state.

5.7 Exercises

Exercise 5.1
What is the difference between a primitive and an abstract behavior?
Exercise 5.2
Define:

a. behavior table
b. causal chain
c. coordinated control programy

Exercise 5.3
Can the perceptual schema and the motor schema for a behavior execute asynchro-
nously, that is, have different update rates?
Exercise 5.4
Fig. 5.2 shows two methods of implementing a potential fields-based follow-corridor
behavior. A third way is to have two instances of a move-away-from-wall (perpen-
dicular) behavior with a move-parallel-to-wall behavior. What are the advantages
and disadvantages of such an implementation?

Exercise 5.5
List and describe the steps in designing a reactive system.