ChronoLLM: Customizing Language Models for Physics-Based Simulation Code Generation

TL;DR

This paper demonstrates how refining large language models can create virtual assistants that effectively generate and assist with physics-based simulation scripts, exemplified by PyChrono, enhancing usability for experts.

Contribution

It introduces a framework for customizing LLMs to generate and improve simulation scripts for PyChrono, facilitating easier access and use of complex physics simulation tools.

Findings

Refined LLMs produce higher quality simulation scripts.

Generated scripts serve as effective starting points for users.

LLMs can answer API questions and suggest modeling approaches.

Abstract

This contribution is concerned with the following issue: can pretrained large language models (LLMs) be refined and customized to the point where they become virtual assistants helping experts with the effective use of a simulation tool? In this case study, the ``simulation tool'' considered is PyChrono, an open source multi-physics dynamics engine for multibody systems. We present a framework for refining and customizing both open- and closed-source LLMs to harness the power of AI in generating scripts that perform PyChrono virtual experiments. We refine and customize several classes of LLMs through a process that leads to a quantifiable improvement in the quality of the generated PyChrono simulation scripts. These scripts can range from simple single-pendulum simulations to complex virtual experiments involving full vehicles on deformable terrain. While the generated scripts are rarely perfect, they often serve as strong starting points for the user to modify and improve on. Additionally, the LLM can answer specific API questions about the simulator, or recommend modeling approaches. The framework discussed is general and can be applied to lower the entry barrier for simulation tools associated with other application domains.