Case-based reasoning systems have traditionally been used to perform h
igh-level reasoning in problem domains that can be adequately describe
d using discrete, symbolic representations. However, many real-world p
roblem domains, such as autonomous robotic navigation, are better char
acterized using continuous representations. Such problem domains also
require continuous performance, such as on-line sensorimotor interacti
on with the environment, and continuous adaptation and learning during
the performance task. This article introduces a new method for contin
uous case-based reasoning, and discusses its application to the dynami
c selection, modification, and acquisition of robot behaviors in an au
tonomous navigation system, SINS (self-improving navigation system). T
he computer program and the underlying method are systematically evalu
ated through statistical analysis of results from several empirical st
udies. The article concludes with a general discussion of case-based r
easoning issues addressed by this research.