5 papers
CompCPZ: Preserving Multi-Modal Intent in Language-Guided Robot Manipulation
Zhen Zhang, Ahmad Hafez, Peng Xie +3
A robot asked to "place the cup near the red plate or the blue plate" may reach the centroid between them and appear geometrically successful, while satisfying neither disjunct of…
Cross-View Correspondence Is a Measurement Intervention: Two-Sided Validation for Agent Evaluation and Credit Assignment
Zhen Zhang, Ahmad Hafez, Amr Alanwar
Agent evaluations and trace-based learning often compare outputs across transformed views through a post-response correspondence treated as neutral preprocessing. We show that this…
Certifying Plans under Model Mismatch: A Trilemma for Reachability from Scarce Data
Yanliang Huang, Zhen Zhang, Ahmad Hafez +4
Sim-to-real policies are designed under nominal dynamics, but target-system trials may yield only a few isolated one-step transitions. We study pre-execution certification of a fix…
Transformer-Accelerated Interpolated Data-Driven Reachability Analysis from Noisy Data
Zhen Zhang, Ahmad Hafez, Peng Xie +3
Data-driven reachability analysis provides guaranteed outer approximations of reachable sets from input-state measurements, yet each propagation step requires a matrix-zonotope mul…
Safe LLM-Controlled Robots with Formal Guarantees via Reachability Analysis
Ahmad Hafez, Alireza Naderi Akhormeh, Amr Hegazy +1
The deployment of Large Language Models (LLMs) in robotic systems presents unique safety challenges, particularly in unpredictable environments. Although LLMs, leveraging zero-shot…