Healthcare applications with the Internet of Things (IoT) are often safety-critical, thus, require extensive testing. Such applications are often connected to smart medical devices from various vendors. System-level testing of such applications requires test infrastructures physically integrating medical devices, which is time and monetary-wise expensive. Moreover, applications continuously evolve, e.g., introducing new devices and users and updating software. Nevertheless, a test infrastructure enabling testing with a few devices is insufficient for testing healthcare IoT systems, hence compromising their dependability. In this paper, we propose a model-based approach for the creation and operation of digital twins (DTs) of medicine dispensers as a replacement for physical devices to support the automated testing of IoT applications at scale. We evaluate our approach with an industrial IoT system with medicine dispensers in the context of Oslo City and its industrial partners, providing healthcare services to its residents. We study the fidelity of DTs in terms of their functional similarities with their physical counterparts: medicine dispensers. Results show that the DTs behave more than 92% similar to the physical medicine dispensers, providing a faithful replacement for the dispenser.

翻译：物联网（IoT）医疗应用通常具有安全关键性，因此需要广泛测试。此类应用常连接来自不同厂商的智能医疗设备。系统级测试需要物理集成医疗设备的测试基础设施，这在时间和成本上均十分昂贵。此外，应用持续演进（如引入新设备和新用户、更新软件）。然而，仅支持少量设备测试的测试基础设施不足以测试医疗物联网系统，从而损害其可靠性。本文提出一种基于模型的方法，用于创建和运行医疗分配器的数字孪生（DTs），以替代物理设备支持大规模物联网应用的自动化测试。我们结合奥斯陆市及其工业合作伙伴为居民提供医疗服务的实际场景，在配备医疗分配器的工业物联网系统中评估该方法。我们研究数字孪生在功能相似性方面与物理对应物（医疗分配器）的保真度。结果表明，数字孪生与物理医疗分配器的行为相似度超过92%，可作为分配器的可靠替代方案。