Organizations: Nanjing University of Aeronautics and Astronautics, Nanjing, China · Tsinghua University, Beijing, China · Nanjing University, Nanjing, China
World-model controllers rely on action-conditioned dynamics for prediction and planning, yet real control systems often execute commands asynchronously due to communication delay, packet loss, reordering, and actuator buffering. We study how asynchronous execution changes the action semantics assumed within world-model controllers, rather than treating it only as an external control disturbance. Through controlled interventions, we identify two architecture-dependent failure modes: planning-based controllers such as TD-MPC2 suffer from a future-action timeline mismatch between imagined and executed action sequences, while recurrent world models such as DreamerV3 can attribute observed transitions to commands that were not actually applied. Our analysis shows that TD-MPC2 requires the correct future action sequence during latent dynamics rollout, whereas DreamerV3 requires timely attribution of each transition to the action that generated it. Based on these findings, we introduce two lightweight execution-consistent interfaces, Future-Sequence for TD-MPC2 and Applied-Action Feedback for DreamerV3, that correct these mismatches without modifying the pretrained world models. Experiments across delays, packet loss, reordering, multiple control domains, measured network traces, and a process-separated asynchronous stack consistently support both diagnoses and the corresponding architecture-specific corrections.
Figures & tables
Figure 1: (a) Synchronous execution keeps commanded and applied actions aligned. Under asynchronous execution, (b) TD-MPC2 suffers from future-action timeline mismatch, while (c) DreamerV3 can suffer from previous-action attribution mismatch.
Figure 2: Effect of execution delay under fixed commands. Error bars denote 95% confidence intervals.
Figure 3: TD-MPC2 execution-information ablations. Left: information type across perturbations. Right: insertion point. Brackets and error bars denote 95% CIs.
Figure 4: DreamerV3 feedback alignment under random delay.
Figure 5: Overview of our execution-consistent world-model control framework.
Table 1: Normalized TD-MPC2 return under different execution interfaces, averaged equally across tasks and normalized by matched clean Single-Action return. Bold and underlined values mark the best and second-best TD-MPC2 results excluding the Oracle.