TITLE:
Exploiting Virtual Elasticity of Production Systems to Respect OTD—Part 3: Basic Considerations for Modelling CPPS Characterized by Non-Ergodic Order Entry and Non-Deterministic Product-Mix for Fully Flexible Addressable Workstations
AUTHORS:
Bruno G. Rüttimann, Martin T. Stöckli
KEYWORDS:
On-Time-Delivery, Production System, Industry 4.0, CPPS, IoT, Stochastic Arrival Rate, Non-Ergodic Process, Virtual Elasticity, Production Capacity, Nominal Mean Exit Rate, Theorem of Non-Ergodicity, Non-Deterministic Product-Mix, TFL, AGV, Scheduling Algorithm, Digital Twin
JOURNAL NAME:
American Journal of Operations Research,
Vol.12 No.2,
February
25,
2022
ABSTRACT: The recently experienced hype concerning the so-called “4th Industrial Revolution” of production systems
has prompted several papers of various subtopics regarding Cyber-Phdysical
Production Systems (CPPS). However, important aspects such as the modelling of CPPS to understand the theory regarding the performance of highly non-ergodic and
non-deterministic flexible manufacturing systems in terms of Exit
Rate (ER), Manufacturing Lead Time (MLT), and On-Time Delivery (OTD) have not
yet been examined systematically and even less modeled analytically. To
develop the topic, in this paper, the prerequisites for modelling such systems are defined in order to be able to derive an explicit and dedicated production mathematics-based understanding of CPPS and its dynamics: switching from
explorative simulation to rational modelling of the manufacturing “physics” led to an own and specific manufacturing theory. The
findings have led to enouncing, among others, the Theorem of Non-Ergodicity as well as the Batch Cycle Time
Deviation Function giving important
insights to model digital twin-based CPPS for complying with the mandatory OTD.