On the effectiveness of Large Language Models in the mechanical design domain
Daniele Grandi, Fabian Riquelme
TL;DR
This work probes the effectiveness of large language models in the mechanical design domain by leveraging domain-specific semantic names from the ABC CAD dataset. It introduces two unsupervised evaluation tasks—binary sentence-pair entailment and zero-shot assembly-name prediction—and demonstrates that a contrastively pre-trained Bert variant substantially outperforms baselines on assembly-name prediction, achieving a top-1 accuracy of 0.386. The results reveal notable failure modes tied to data scarcity, high lexical diversity, and non-semantic labels, while offering concrete guidance on fine-tuning strategies (learning rate, sequence length, dropout, and multi-head attention) to mitigate overfitting. Overall, the study provides a foundation for applying domain-adapted transformer models to CAD-related language and suggests directions for generative and data-augmentation approaches to better support mechanical designers.
Abstract
In this work, we seek to understand the performance of large language models in the mechanical engineering domain. We leverage the semantic data found in the ABC dataset, specifically the assembly names that designers assigned to the overall assemblies, and the individual semantic part names that were assigned to each part. After pre-processing the data we developed two unsupervised tasks to evaluate how different model architectures perform on domain-specific data: a binary sentence-pair classification task and a zero-shot classification task. We achieved a 0.62 accuracy for the binary sentence-pair classification task with a fine-tuned model that focuses on fighting over-fitting: 1) modifying learning rates, 2) dropout values, 3) Sequence Length, and 4) adding a multi-head attention layer. Our model on the zero-shot classification task outperforms the baselines by a wide margin, and achieves a top-1 classification accuracy of 0.386. The results shed some light on the specific failure modes that arise when learning from language in this domain.
