From Optimizable to Interactable: Mixed Digital Twin-Empowered Testing of Vehicle-Infrastructure Cooperation Systems

Abstract

Sufficient testing under corner cases is critical for the long-term operation of vehicle-infrastructure cooperation systems (VICS). However, existing corner-case generation methods are primarily AI-driven, and VICS testing under corner cases is typically limited to simulation. In this paper, we introduce an L5 ''Interactable'' level to the VICS digital twin (VICS-DT) taxonomy, extending beyond the conventional L4 ''Optimizable'' level. We further propose an L5-level VICS testing framework, IMPACT (Interactive Mixed-digital-twin Paradigm for Advanced Cooperative vehicle-infrastructure Testing). By enabling direct human interactions with VICS entities, IMPACT incorporates highly uncertain and unpredictable human behaviors into the testing loop, naturally generating high-quality corner cases that complement AI-based methods. Furthermore, the mixedDT-enabled ''Physical-Virtual Action Interaction'' facilitates safe VICS testing under corner cases, incorporating real-world environments and entities rather than purely in simulation. Finally, we implement IMPACT on the I-VIT (Interactive Vehicle-Infrastructure Testbed), and experiments demonstrate its effectiveness. The experimental videos are available at our project website: https://dongjh20.github.io/IMPACT.

Figures (11)

• Figure 1: Schematics for classical DT and mixedDT. (a) In classical DT, virtual entities are typically digital counterparts of the physical ones. (b) In mixedDT, virtual entities exist independently and the physical and virtual entities are integrated into the unified mixed space, where they can coexist and interact with each other.
• Figure 2: Schematic of I-VIT, IMPACT's practical implementation. In the mixed testbed, the physical vehicles and infrastructure in the physical testbed (outlined in gold), the virtual vehicles and infrastructure in the virtual testbed (outlined in cyan), the virtual vehicle in the virtual environment of a driving simulator (outlined in red) and human operators in the HMI testbed operate synchronously and interact seamlessly across environments in real time. Consequently, I-VIT is an interactive VICS-DT testing environment, where human operators can directly interact with the physical and virtual entities in I-VIT. The demonstration videos are available at our project website: https://dongjh20.github.io/IMPACT.
• Figure 3: System architecture of the IMPACT framework, consisting of the physical, virtual, mixed testing environments and the interactive environment.
• Figure 4: Mechanisms for scenario visualization and operational intent processing via HMI devices and their corresponding implementation examples.
• Figure 5: Illustration of data interactions within the IMPACT framework and its implementation, the I-VIT platform.