This paper systematically studies the Influence of microstructure parameters and magnetic intensity on flexible pressure sensor with variable stiffness. As for the fabrication, we firstly fabricate the microstructure array with magnetic induction characteristic by 3D dynamic laser, and than sputter and pattern a pair of 80 nm thick Au electrodes on PET film. Finally, we package the microstructure array and PET film to get a variable stiffness flexible pressure sensor. The stiffness of the magnetically induced microstructure can be increased by applying a magnetic field. The performance of the sensor was tested under different magnetic intensity. The experimental results show that when the magnetic intensity is 0 mT, the sensor had higher sensitivity under low pressure load, but the linearity became worse with the continuous increase of pressure load. When the magnetic intensity is 250 mT, the sensitivity of the sensor decreases under low pressure load, but it had good linearity under both low and high pressure load.
The monitoring of the knee joint angle during lower-limb motions is crucial for knee disorders patients and their rehabilitation. However, commonly used methods for lower-limb motion detection, such as inertial measurement units (IMUs) and motion capture systems, have limitations such as drift and high cost. To address these issues, we developed a wearable kneepad sensor using textile resistive strain sensors to measure knee angle during lower-limb motion. The strain sensors change in resistance signals caused by their deformation of them when the knee joint bends. To improve the accuracy of knee angle measurements, an encoder was integrated with kneepad sensor onto a prosthetic limb and used linear mapping method to calibrate the kneepad sensor with the encoder data as the ground truth. The calibrated kneepad sensor achieved an R$^{2}$ value of 0.956, MAE of 6.15°, and MSE of 64.35 while detecting the knee angle. It was demonstrated that the ability of the kneepad sensor to measure knee angles during two types of lower-limb motions, sit-to-stand (STS) and knee extension. It is shown in this work that this comfortable, wearable kneepad sensor can help detect knee angles during lower-limb motions in various environments and has broad applications in healthcare and robotics.
In this paper, a novel electrodes design for in-plane measurement of single-structure quadruple mass multi-axis MEMS inertial devices is proposed to achieve the closed-loop x/y-axis acceleration measurement. The designed 45 ° tilting comb electrodes combine synovial comb electrodes and laminated comb electrodes and meet the same electrostatic force coefficient on quadruple mass, with structural symmetry design ensured. Theoretical formula is analyzed in detail, which provides guidance for simulation and design.
In this paper, a wearable brain-computer interface system based on flexible and air-permeable electronic skin is implemented. Wearable brain-computer interfaces need to be expanded into more aspects of daily life. Research in these areas requires devices that are closer to life. The flexible electronic skin has the advantages of high permeability (1.904 kg $\cdot \mathrm{m}^{-2} \cdot$ day $^{-1}$ at body temperature) and low skin contact impedance ($4.683 \mathrm{k} \Omega$ at 1 kHz), and can be used to expand the research of single lead brain computer interface in the field of appetite. Because the orbitofrontal cortex plays an important role in food decisions, the device placed electrodes on the forehead to collect electrical signals from people when they were presented with images of different delicacies. Watching their brain activity as they made judgments about their food choices. Found that it was possible to distinguish between delicious pictures and boring ones. To look at the brain’ s attraction and rejection decisions when faced with food cues.
We developed a nano-operating system that features a stereoscopic display of AFM images that is updated in real time. In order to accurately judge the positional relationship between the nanoparticles and carry out operations, the operator is able to use this system to not only observe the change process of the nano-environment in real time while the AFM is operating, but also obtain depth information with the help of a real-time stereoscopic display. At the same time, we give the operator with a corresponding perspective in real time by obtaining the changes in the operator’s head posture. This helps to increase the sense of presence and improves operational efficiency.
