This book covers a variety of topics in the field of mechanical engineering, with a special focus on methods and technologies for modeling, simulation, and design of mechanical systems. Based on a set of papers presented at the 1st International Conference “Innovation in Engineering”, ICIE, held in Guimarães, Portugal, on June 28–30, 2021, it focuses on innovation in mechanical engineering, spanning from engineering design and testing of medical devices, evaluation of new materials and composites for different industrial applications, fatigue and stress analysis of mechanical structures, and application of new tools such as 3D printing, CAE 3D models, and decision support systems.  This book, which belongs to a three-volume set, provides engineering researchers and professionals with extensive and timely information on new technologies and developments in the field of mechanical engineering and materials.