# Projection-Based Augmented Reality Assistance for Manual Electronic Component Assembly Processes
## 1 Introduction  
It is evident that initiatives such as the German paradigm of \"Industry 4.0\" or some other similar ones all around the world are having a deep impact on the manufacturing sector, and thus are reshaping the industry. The development of such paradigms is accelerating the development and deployment of advanced ITC-related technologies [1], transforming many aspects, such as the industrial workforce and the way they develop their tasks. Even though customer-centric and demand-driven production is moving forward through the progress of industrial automation, the need for a better and more empowered human workforce is more demanding than ever. The next human workforce should have new and more powerful tools that allow them to improve their decision-making processes, to more easily adapt to changing production conditions and to adopt strategies for continuous training. Along with the development of the Industry 4.0 paradigm appears the concept of Operator 4.0 [2]. This concept is driven by several objectives, such as to simplify the day-to-day work, while improving efficiency and autonomy by focusing on added value tasks, all in a comfortable and healthy working environment. This paper proposes a new system based on augmented reality (AR) for assisting operators during manual assembly of electronic components. As mentioned before, a customer-centric oriented and personalized production requires continuous changes in production lines. The electronics sector is not an exception in this regard. This industry has many automated processes for the assembly of electronic components for electronic boards, also known as printed circuit boards (PCB), but there are also many manual assembly stages along the production lines. Operators perform the monotonous task of board assembly over considerable periods of time; therefore, they are likely to experience fatigue and distractions. Furthermore, the low profile needed for this task favors rotation of personnel, which is undesirable because new employees take a certain amount of time to adapt. As a consequence, manual processes have the highest error ratio of the production process; electronic manufacturers have identified the necessity of improving these processes as a key point. Therefore, This paperproposes a system which aims to reduce assembly errors and adaptation times for new employees while increasing operator comfort, confidence and assembling speed by means of AR.  
This paper is structured as follows: Section 2 describes the current state of the art related works with the application of augmented reality to the manufacturing sector. In Section 3, we show our approach to assist the operators during the manual assembly of electronic components. Section 4 outlines the results of a usability test we carried out with several operators using the proposed approach. Section 5 discusses the proposed approach and shows how a significant and positive impact has been achieved in the production line evaluated. Finally, Section 6 gives some conclusive remarks and also mentions some future research directions for improving the next generation of the system.