Additive manufacturing methods: techniques, materials, and closed-loop control applications

Additive manufacturing encompasses a set of low-cost and highly versatile tools used to prototype and fabricate three-dimensional (3D) objects with ease. In most of the additive manufacturing techniques, materials are deposited layer by layer until a 3D object is reproduced. Several additive manufacturing techniques have been developed in the previous decade, and the application of additive manufacturing has increased in various industrial sectors. However, there are still drawbacks associated with additive manufacturing techniques, necessitating further study and development. In this study, we review the techniques and materials used in additive manufacturing. The vast majority of additive manufacturing processes are still based on open-loop control or implement some local controllers for specific variables (such as temperature), making them susceptible for errors. This study presents a review of the different additive manufacturing techniques, examples of academic and commercial efforts to improve the control systems for additive manufacturing, as well as the application of additive manufacturing in different fields such as aerospace, electronics, arts, and biomedical. The article ends highlighting the advantages of utilizing a closed-loop control system in additive manufacturing and discussing the work needed for further development.