# Automation and Robotics Pilot Lines in the Context of Industry 5.0
## 1 Introduction
These changes, in hardware, and particularly in software, are becoming even faster and more impactful due to the rapid evolution of AI and robotics [10]. Therefore, it is necessary to have methods, strategies, and tools that help reduce uncertainty on such innovations and serve as a bridge between research and market needs. Often, Technology Readiness Levels (TRLs) are presented as a measure of maturity and as a scale to evaluate the degree of development of a technology. These levels, which originated from NASA [11], range from identifying basic principles to operating the technology in real-world environments. Between these two extremes, there are several intermediate steps that include scientific risk reduction, proof of concepts, laboratory tests, and validation and demonstration in relevant settings such as pilot lines or pilot plants. Pilot lines are a relevant element in this advance along the TRL scale, particularly when developing solutions that facilitate quality improvement and waste reduction. A pilot line is a small-scale version of a production system used to test, evaluate, adapt, or even refine products, processes, or technologies. It serves as an intermediate step between research and full-scale production, facilitating the research and development (R&D) and serving as a test-before-invest environment [12], all without disrupting ongoing production processes. Pilot lines play a crucial role in validating the technical viability and reducing risks. They are also a valuable tool for experimentation during the early stages of product design and for rapid prototyping [13]. Furthermore, pilot lines facilitate the production of proof-of-concept batches, enabling their use in refining the designs. Additionally, they serve as tools for technology adaptation and optimization, and represent a valuable complement in the human-technology-sustainability aspects of Industry 5.0. In this context, this article aims to understand the usefulness of pilot lines as an intermediate step between research and production, while analyzing the status of pilot linesin Industries 4.0 and 5.0. It also seeks to detail how the \"Group of advanced Automation of Machines, Highly complex processes and Environments\" (GAMHE) 5.0 pilot line has been designed and implemented. Additionally, it presents, from an applied perspective, a collection of case studies where this pilot line has been used in the industrial field. To achieve these objectives, the following points are addressed:  
* Analysis of the state of the art related to pilot lines in different industries;
* Critical comparison of pilot lines for automation and robotics;
* Design and implementation of the GAMHE 5.0 pilot line;
* Demonstration of the use of the pilot line in several industrial cases studies;
* Discussion on the benefits and possible negative impacts of pilot lines. These points are detailed in the following sections. Section 2 details the state of the art and provides an extensive review of automation and robotics pilot lines. Section 3 presents the GAMHE 5.0 line and details how it addresses the needs of Industry 5.0. Section 4 provides the information of case studies developed and validated on the pilot line. Finally, Sections 5 and 6 provide the discussion, the conclusions, and future work.