# I4.0I: A New Way to Rank How Involved a Company Is in the Industry 4.0 Era
## 1 Introduction  
The Industry 4.0 (I4.0) concept has been growing during the last years and has become one of the most discussed topics in the industrial and academic fields [1, 2]. Many countries have already implemented local programs to improve the development and adoption of the Industry 4.0 methodology. For example, in 2012, the German government launched the initiative called \"High-Tech Strategy 2020\" [3]; before that, in 2011, the USA introduced the \"Advanced Manufacturing Partnership\" [4]; in China, the \"Made in China 2025\" was presented in 2015 [5] and two years earlier, France created \"La Nouvelle France Industrielle\" [6]. Accordingly, [PERSON] et al. [7] stated that \"the Industry 4.0 paradigm and its technologies are transforming the economy and its production\". The fourth industrial revolution aims to focus on intelligent manufacturing [3], which involves the integration of factory with supply-chain activities, product life cycle [8], and even the workforce [9], through applying digital technologies. With big-data approaches and cyberphysical systems (CPS), it is possible to implement real-time monitoring methods, develop optimization algorithms, and control precisely all devices. Beyond that, the integration, cooperation, and communication between the virtual and real environments can be easily deployed [10]. Overall, multinationals have also structured several optimization initiatives that include business technologies approaches, such as enterprise resource planning (ERP), manufacturing execution systems (MES), and others [11]. Furthermore, itis possible to conclude that factory optimization has a very sophisticated technology architecture. Due to the high precision, control, reliability, and efficiency required by Industry 4.0, the implementation of smart manufacturing is not an easy and inexpensive task. To be successful in today's competitive environment, manufacturing companies must be able to fabricate high-quality, low-cost products and provide better customer service [12]. Accordingly, manufacturing companies are striving to sustain their specific characteristics of productivity, efficiency, and product quality [13]. While companies' profits are growing marginally, competition is becoming fierce [14] and therefore, those companies that fail to adopt Industry 4.0 will struggle to remain competitive and active on the market. Some studies have been carried in the field with the intent to assess a manufacturer's capability and measure the maturity and readiness level of a company on implementing smart manufacturing and create road maps [15; 16; 17; 18; 19; 20; 21; 22; 23]. However, performance measurements of the Industry 4.0 transformation are still uncertain [24], and none of the models mentioned focus only on the technologies of Industry 4.0 and present all their characteristics. Moreover, there is a lack of a linear, numerical, and more straightforward indicator that classifies each company individually, enabling them to see and understand at what level of Industry 4.0 they are. Furthermore, we envisage that this index must be useful for companies to compare themselves with competitors, creating a more competitive industrial environment, in which all companies constantly seek the highest index to capture customers' attention. In this context, we analyzed the state of the art, compared relevant solutions already present until January 2023, and separated and described all technologies involved with Industry 4.0. This analysis promoted the creation of a classifying ranking named I4.0I (Industry 4.0 Index). The I4.0I measures the degree of maturity and suitability of a particular company in the context of I4.0 technologies. To evaluate the I4.0I, we developed a questionnaire that was sent to industries in Brazil. Based on the answers, we established how involved a company was in the Industry 4.0 era. The results were passed as feedback to the companies, and final discussions were encouraging, showing our proposal's assertiveness.