Book excerpt: Smart Materials in Additive Manufacturing, Volume Three: 4D-Printed Robotic Materials, Sensors, and Actuators covers the principles, real-world use, and advances in the cutting-edge field of 4D printed smart robotic materials. It discusses the mechanics of these materials, techniques by which to manufacture them, and different applications. Detailed modeling and control techniques are outlined, illustrating their use in real-world settings. Shape memory polymers, hydrogels, shape memory alloys, biomaterials, natural fibers, dielectric elastomers, liquid crystal elastomers, electroactive polymers, and more materials are covered, featuring in-depth discussion of their responses to stimuli, fabrication, multi-physics modeling, control techniques, and applications. - Discusses the design, modeling, simulation, and manufacturing processes of various 4D-printed robotic materials - - Outlines modeling and control techniques to illustrate the use of smart robotic materials - Provides case studies demonstrating real-world situations where the techniques, materials, and concepts discussed have been successfully deployed - Covers applications including robotics, metamaterials, micromachines, sensors, bioprinting, and actuators