HCSM
- 1 July 1995
- journal article
- Published by Association for Computing Machinery (ACM) in ACM Transactions on Modeling and Computer Simulation
- Vol. 5 (3), 242-267
- https://doi.org/10.1145/217853.217857
Abstract
This paper presents HCSM, a framework for behavior and scenario control based on communicating hierarchical, concurrent state machines. We specify the structure and an operational execution model of HCSM's state machines. Without providing formal semantics, we provide enough detail to implement the state machines and an execution engine to run them. HCSM explicitly marries the reactive (or logical) portion of system behavior with the control activities that produce the behavior. HCSM state machines contain activity functions that produce outputs each time a machine is executed. An activity function's output value is computed as a function of accessible external data and the outputs of lower-level state machines. We show how this enables HCSM to model behaviors that involve attending to multiple concurrent concerns and arbitrating between conflicting demands for limited resources. The execution algorithm is free of order dependencies that cause robustness and stability problems in behavior modeling. In addition, we examine the problems of populating virtual environments with autonomous agents exhibiting interesting behavior and of authoring scenarios involving such agents. We argue that HCSM is well suited for modeling the reactive behavior of autonomous agents and for directing such agents to produce desired situations. We demonstrate use of HCSM for modeling vehicle behavior and orchestrating scenarios in the Iowa Driving Simulator, an immersive real-time virtual driving environment.Keywords
This publication has 16 references indexed in Scilit:
- VRLOCO: Real-Time Human Locomotion from Positional Input StreamsPRESENCE: Virtual and Augmented Reality, 1996
- The Iowa Driving Simulator: an immersive research environmentComputer, 1995
- Multi-level direction of autonomous creatures for real-time virtual environmentsPublished by Association for Computing Machinery (ACM) ,1995
- Dramatic PresencePRESENCE: Virtual and Augmented Reality, 1993
- Control of discrete event systems modeled as hierarchical state machinesIEEE Transactions on Automatic Control, 1993
- Virtual Reality, Art, and EntertainmentPRESENCE: Virtual and Augmented Reality, 1992
- Designing autonomous agents: Theory and practice from biology to engineering and backRobotics and Autonomous Systems, 1990
- STATEMATE: a working environment for the development of complex reactive systemsIEEE Transactions on Software Engineering, 1990
- Statecharts: a visual formalism for complex systemsScience of Computer Programming, 1987
- A robust layered control system for a mobile robotIEEE Journal on Robotics and Automation, 1986