Hydrogels possess exceptional physical and chemical properties that render them appealing components for soft actuators, wearable technologies, healthcare devices, and human interactive robots. Especially, the stimuli-responsive hydrogels can sense and perform smart functions in the presence of various stimuli that collectively contribute to the intelligence of the soft machine systems. Furthermore, facile modification of hydrogels with other functional groups/additives/nanofillers substantially expands their functionalities and further broadens the scope of their application. Designing suitable hydrogels with adequate capabilities and engineering effective configurations are of supreme importance for the development of advanced hydrogel-based soft machines. Herein, this review summarizes recent advances of stimuli-responsive hydrogels in multifunctional soft machines, such as robotics, actuators, and sensors. Functions including multistimuli responsiveness, self-healing, and high biocompatibility can be endowed to the soft machines through designing advanced hydrogel materials, which would not be possible with an approach based on conventional elastic materials (e.g. rubbers, elastomers). To close, future opportunities and challenges this field faces are emphasized and discussed for the development of exciting new hydrogel-based devices in real-world conditions.

水凝胶具有出色的物理和化学特性，使其成为软致动器，可穿戴技术，医疗保健设备和人机交互机器人的理想之选。特别是，在多种刺激的共同作用下，刺激响应性水凝胶可以感知并执行智能功能，这些刺激共同有助于软机系统的智能化。此外，用其他官能团/添加剂/纳米填料容易地修饰水凝胶大大扩展了它们的功能性并进一步拓宽了其应用范围。设计具有足够功能和工程有效配置的合适水凝胶对于开发先进的基于水凝胶的软机至关重要。在这里 这篇综述总结了在诸如机器人，致动器和传感器等多功能软机中刺激响应水凝胶的最新进展。通过设计先进的水凝胶材料，软机可以赋予多种刺激响应性，自我修复和高生物相容性等功能，而这是基于传统弹性材料（例如橡胶，弹性体）的方法所无法实现的。最后，强调并讨论了该领域面临的未来机遇和挑战，以开发在现实条件下令人兴奋的新型水凝胶基设备。这是基于常规弹性材料（例如橡胶，弹性体）的方法所无法实现的。最后，强调并讨论了该领域面临的未来机遇和挑战，以开发在现实条件下令人兴奋的新型水凝胶基设备。这是基于常规弹性材料（例如橡胶，弹性体）的方法所无法实现的。最后，强调并讨论了该领域面临的未来机遇和挑战，以开发在现实条件下令人兴奋的新型水凝胶基设备。