From Molecules to Machines: A Multiscale Roadmap to Intelligent, Multifunctional Soft Robotics.

Soft robots, with their exceptional compliance, adaptability, and ability to safely interact with delicate objects, are redefining human-machine interfaces and expanding robotic capabilities into environments inaccessible to rigid systems. However, creating intelligent, multifunctional soft robots demands navigating a complex, multiscale design landscape, ranging from molecular-level building blocks through multifunctional soft robotic materials to fully integrated systems. In this review, we present a structured roadmap that addresses key challenges at three critical scales. At the molecular level and nanoscale, we examine an extensive library of soft matter and functional nanomaterials that impart tunable mechanical, electrical, optical, and stimuli-responsive properties to soft robotic materials. At the microscale, we highlight effective assembly strategies, such as heterogeneous blending, bilayer integration, and additive manufacturing, enabling reconfigurable, multifunctional materials that combine rapid response, robust functionality, large deformation tolerance, and fatigue resistance. Finally, at the system level, we explore how integrating actuation mechanisms, sensing technologies, and computational tools with these advanced materials can yield intelligent, adaptive, and energy-efficient soft robotic systems. By bridging these multiscale gaps and fostering interdisciplinary collaborations, this review provides near-, mid-, and long-term perspectives to guide future research, ultimately driving the development of transformative soft robots that elevate human-machine interactions.