Real-time behavior-based robot control

Abstract

Behavior-based systems form the basis of autonomous control for many robots, but there is a need to ensure these systems respond in a timely manner. Unexpected latency can adversely affect the quality of an autonomous system's operations, which in turn can affect lives and property in the real-world. A robots ability to detect and handle external events is paramount to providing safe and dependable operation. This paper presents a concurrent version of a behavior-based system called the Real-Time Unified Behavior Framework, which establishes a responsive basis of behavior-based control that does not bind the system developer to any single behavior hierarchy. The concurrent design of the framework is based on modern software engineering principles and only specifies a functional interface for components, leaving the implementation details to the developers. In addition, the individual behaviors are executed by a real-time scheduler, guaranteeing the responsiveness of routines that are critical to the autonomous system's safe operation. Experimental results demonstrate the ability of this approach to provide predictable temporal operation, independent of fluctuations in high-level computational loads.

Unified behavior framework in discrete event simulation systems

“…The UBF was developed as a means to address this inflexibility with implementing behavior-based architectures, specifically at the controller level of the three-layer architecture. 1,9 By separating the behaviors from the controller, different architectures can be implemented into the behavior logic without having to change the controller. This also frees the behavior logic from being application specific and encourages reuse.…”

“…Here in this section a description of the UBF is given following the definition from Woolley and co-workers. 1,9…”

“…Different approaches to agent design offer developers different advantages to help combat these effects. 1…”

“…The Unified Behavior Framework (UBF) has been identified as an effective means to improve upon this shortfall without sacrificing the benefits of BTs, as a UBF tree is composed of behaviors which are re-usable through modularity, and also allow for the blending of action outputs of behaviors, as the UBF draws a delineation in design (i.e., a separation of concerns) between the behavior logic and the controller. 1,9…”

“…Next a detailed overview of the UBF is given following the definition from Woolley and co-workers. 1,9 In Section 4 results are presented for implementing the UBF into AFSIM using an attack on an integrated air defense system (IADS) scenario. Lastly conclusions and future work are presented.…”