Real-World Planning with PDDL+ and Beyond

TL;DR

Nyx, a novel PDDL+ planner built to emphasize lightness, simplicity, and, most importantly, adaptability, is presented, designed to be effortlessly customizable to expand its capabilities well beyond the scope of PDDL+.

Abstract

Real-world applications of AI Planning often require a highly expressive modeling language to accurately capture important intricacies of target systems. Hybrid systems are ubiquitous in the real-world, and PDDL+ is the standardized modeling language for capturing such systems as planning domains. PDDL+ enables accurate encoding of mixed discrete-continuous system dynamics, exogenous activity, and many other interesting features exhibited in realistic scenarios. However, the uptake in usage of PDDL+ has been slow and apprehensive, largely due to a general shortage of PDDL+ planning software, and rigid limitations of the few existing planners. To overcome this chasm, we present Nyx, a novel PDDL+ planner built to emphasize lightness, simplicity, and, most importantly, adaptability. The planner is designed to be effortlessly customizable to expand its capabilities well beyond the scope of PDDL+. As a result, Nyx can be tailored to virtually any potential real-world application requiring some form of AI Planning, paving the way for wider adoption of planning methods for solving real-world problems.

Figures (4)

• Figure 1: Examples of PDDL plan metrics.
• Figure 2: PDDL-style implementation of sin($\theta^\circ$) and cos($\theta^\circ$) using Bhaskara's approximation.
• Figure 3: Absolute value of some variable $z$ and the magnitude of some vector $\vec{v}$, using Nyx's added power operator $^\wedge$.
• Figure 4: Fuel system Modelica model simulated inside Nyx's semantic attachment as an FMU.