The Concurrent, Continuous Fluent Calculus

The Fluent Calculus A Specification Language for Robots with Sensors in Nondeterministic, Concurrent, and Ramifying Environments

From Discrete Task Plans to Continuous Trajectories

We present a logic-based framework to provide robots with high-level reasoning, such as planning. This framework uses the action description language C+ to represent actions and changes, and the system CCALC to reason about them. In particular, we can represent action domains that involve concurrent actions and additive fluents; based on this description, we can compute shortest plans to a plan...

Continuous Processes in the Fluent Calculus

Among the known predicate calculus formalisms for axiomatizing commonsense reasoning about actions, the Fluent Calculus stands out in offering a solution not only to the representational but also the inferential aspect of the fundamental Frame Problem. In this paper we extend this formalism to modeling hybrid systems, which involve both discrete and continuous change. We borrow basic notions fr...

Event Calculus

The event calculus [45, 66, 74, 98, 100] is a formalism for reasoning about action and change. Like the situation calculus, the event calculus has actions, which are called events, and time-varying properties or fluents. In the situation calculus, performing an action in a situation gives rise to a successor situation. Situation calculus actions are hypothetical, and time is tree-like. In the e...

On the Combination of Partial Action Descriptions

We investigate the problems of precondition interactions and eeect cumulations, typically caused by the concurrent execution of actions. Our analysis leads to an integration of property oriented and resource oriented approaches to the representation of action and change. We formalize our ideas by introducing an extension AORC of the Action Description Language AC 2]. In order to enable sound an...