As industries need more real-time monitoring and interconnected systems, the demand for wireless sensors expands. Vibrational energy harvesters are a potential solution for powering these sensors, as vibrations commonly exist where monitoring occurs. Developments in low-power circuitry have also led to the feasibility of these types of harvesters. Electromagnetic harvesters are a standout among various types of vibrational harvesters due to their ability to capture kinetic energy in a low-frequency range. This leads to these devices being more applicable in real-world applications where ambient vibrations are typical of having low frequencies. Hence, extensive research has been undertaken to make electromagnetic harvesters more efficient and compact. This review study aims to examine recent literature that has made advancements and demonstrated the full potential of such devices.
1 December 2020 in Journal of Science: Advanced Materials and Devices
Carbon nanotube yarns are employed to develop environment-friendly, low cost and lightweight paper-based flexible devices for wearable applications in temperature and respiratory monitoring, and personal healthcare.
An integrated vehicle dynamics control (IVDC) algorithm, developed for improving vehicle handling and stability under critical lateral motions, is discussed in this paper. The IVDC system utilises integral and nonsingular fast terminal sliding mode (NFTSM) control strategies and coordinates active front steering (AFS) and direct yaw moment control (DYC) systems. When the vehicle is in the normal driving situation, the AFS system provides handling enhancement. If the vehicle reaches its handling limit, both AFS and DYC are then integrated to ensure the vehicle stability. The major contribution of this paper is in improving the transient response of the vehicle yaw rate and sideslip angle tracking controllers by implementing advanced types of sliding mode strategies, namely integral terminal sliding mode and NFTSM, in the IVDC system. Simulation results demonstrate that the developed control algorithm for the IVDC system not only has strong robustness against uncertainties but also improves the transient response of the control system.
The orientation dependence of the piezoresistive effect of p-type single crystalline 3C-SiC thin film grown on a (100)Si wafer was characterized. The longitudinal, transverse gauge factors in [100] orientation, and longitudinal gauge factor in [110] orientation were found to be 5.8, −5.2, and 30.3, respectively. The fundamental piezoresistive coefficients π11, π12, and π44 of p-type 3C-SiC were obtained to be 1.5 × 10−11 Pa−1, −1.4 × 10−11 Pa−1, and 18.1 × 10−11 Pa−1, respectively. From these coefficients, the piezoresistive effect in any crystallographic orientation in p-type single crystalline 3C-SiC can be estimated, which is very valuable in designing micro-mechanical sensors.
13 May 2008 in Journal of Micromechanics and Microengineering