A Performance Comparison Between a Digital Shadow and a Digital Twin in a Mixed Model Stochastic System

The competition in the current global market has highlighted the importance of having a virtual system that can monitor the entire manufacturing process. Industries face challenges such as shorter lead times, high demand in product variety and a need for a virtual system that can link the physical and the digital world. The virtual systems that are currently available and used for linking the physical system and the digital system, and enable product variety, have certain restrictions. As a result, this article aims to develop a digital shadow and a digital twin as a possible solution. The digital shadow and the digital twin in this article are designed and developed using the MATLAB and SIMULINK platforms. Digital twins and digital shadows are the two leading virtual systems in the ongoing digital transformation era. The aim of this article was to design and develop a digital shadow and a digital twin for a mixed-model stochastic assembly line, to monitor the raw materials, predicts bottlenecks that might occur during the manufacturing process and thereby reduce the cycle time. The two virtual models are given the same customer orders to use as inputs, to run simulations and calculate the cycle time. The models are compared based on their performance per customer order and in overall performance. The results show that the digital twin is more reliable in overall performance than the digital shadow, with a cycle time improvement of 19%.