Experimenting with Digital Twins: A LEGO®-Based Modular Testbed for Systematic Evaluation

Digital twins (DTs) promise improved decision-making under project uncertainty, but real-world implementations are costly and hard to compare. As DT research moves toward tighter feedback loops and greater autonomy, affordable and controllable environments for evaluating such DTs are lacking. This paper presents a modular DT testbed that combines LEGO®-based physical components with Raspberry Pi computers to support controlled variation of DT scenarios, feedback loops and automation levels. Two studies conducted in the testbed illustrate how DTs can be systematically evaluated across computational processes and physical execution. The testbed facilitates cost-effective and repeatable future research on autonomous DTs for construction management.