Recent progress in materials science and engineering towards flexible omnidirectional sensor

With the rapid development of intelligent electronic technology, flexible omnidirectional sensors attract considerable interest due to their capability to detect complex motions in multiple directions, providing a simple and feasible detection tool in the fields of medical health monitoring, Internet of Things, and artificial intelligence by being an important electronic component for information acquisition and transmission. Researchers are actively exploring flexible omnidirectional sensing technology from multidimensional angles, encompassing materials, design, and flexible electronics, to enhance the accuracy and real-time performance of omnidirectional signal monitoring. Here, our review systematically explores the intricate relationship between sensing materials and flexible omnidirectional sensors. First, we discuss the influence of material structure, composition, and properties on the performance of flexible omnidirectional sensors. Then, our comprehensive analysis encompasses a wide range of sensing materials, including metal-based materials, carbon-based materials, and conductive composites. Following, we delve into cutting-edge manufacturing techniques such as screen printing, 3D printing, and electrospinning, and discuss how these methods enable the creation of high-resolution, designable patterns from a materials perspective. Furthermore, we summarize the main application scenarios of flexible omnidirectional sensors in physiological signal monitoring, motion assistance, environmental monitoring, and artificial intelligence. Finally, we discuss the application challenges and prospects of flexible sensing materials in the field of flexible omnidirectional sensors.