Flexible electronics with continuous monitoring ability a extensively preferred in various medical applications. In this work, a flexible pressure sensor based on porous graphene (PG) is proposed for continuous cardiovascular status monitoring. The whole sensor is fabricated in situ by ink printing technology, which grants it the potential for large-scale manufacture. Moreover, to enhance its long-term usage ability, a polyethylene terephthalate/polyethylene vinylacetate (PET/EVA)-laminated film is employed to protect the sensor from unexpected shear forces on the skin surface. The sensor exhibits great sensitivity (53.99/MPa), high resolution (less than 0.3 kPa), wide detecting range (0.3 kPa to 1 MPa), desirable robustness, and excellent repeatability (1000 cycles). With the assistance of the proposed pressure sensor, vital cardiovascular conditions can be accurately monitored, including heart rate, respiration rate, pulse wave velocity, and blood pressure. Compared to other sensors based on self-supporting 2D materials, this sensor can endure more complex environments and has enormous application potential for the medical community.

Joint-related diseases can cause chronic symptoms and severe pain, which can be prevented and evaluated by accurate joint status monitoring. Soft strain sensors with high skin compatibility can detect strains from joint bending, making them a promising solution for joint health monitoring. Practically, over half of free-moving joints on the human body can perform omnidirectional bending, but current soft strain sensor cannot accurately quantify such angles. Moreover, strain-angle relations vary significantly with joint sizes, making sensor calibration difficult or unfeasible. Herein, this work designed and implemented an omnidirectional and size-adaptive soft bending sensor with a 3-D structure to capture pose angles for arbitrary joint bending. A dice manufacture-inspired procedure is proposed to precisely position four soft strain sensing channels. Moreover, by mathematically decoupling strain for deformation distributions, the sensor can calculate omnidirectional bending angles regardless of different joint sizes for the first time. The ability of the sensor was verified by mounting on three vulnerable joints for motion detection, thereby demonstrating its potential for reliable and accurate joint health monitoring.