MAE

This paper presents the development of a ring shaped force sensor for sensorized guidewire applications. The sensor comprises a suspended ring structure located at the center of four suspended beams that can be integrated on the distal tip of a guidewire. SiNWs with a length of 6 µm and a cross section of 90 nm x 90 nm are embedded at the anchor of each silicon bridge as the piezoresistive sensing elements. Taking advantage of the high sensitivity of SiNWs, the fabricated sensor was capable to detect small displacement in nm ranges with a sensitivity of 13.4 x 10 -3 µm -1 in the z-direction. This force sensor showed high linearity (>99.9%) to the applied load and no obvious hysteresis was observed.

Vibration based diagnosis to detect damage in gearboxes has been studied to schedule maintenance and reduce possible capital losses from gearbox failures. However, such vibration based techniques are difficult to implement in planetary gearboxes due to the complex nature of measured vibration spectrum. Motor current signal analysis (MCSA) provides an alternative and non-intrusive way to detect mechanical faults through electrical signatures. However, literature still lacks reported investigation to monitor a planetary gearbox in an electro-mechanical drive-train using MCSA. A successful practical implementation of MCSA to planetary gearboxes is challenging because of the harmonics present in the measured current signal that ariseg from: 1) the structural properties of the electrical machines, and 2) the errors in manufacturing and assembly of large number of gears. This paper proposes a novel fault detection method that extends the resonance demodulation technique from vibration analysis to MCSA for detection of the gear faults where the measured stator current signal may contain high background noise. The capability of this approach is demonstrated through simulation. A nonlinear multi-DOF lumped parameter model is developed for an electro-mechanical drive-train consisting of a driving motor connected through a back-to-back planetary gearbox to a load generator. Afterwards, a seeded gear tooth fault is introduced in this electro-mechanical model to investigate its effect on the stator current. Simulation results result in a higher fault indicator under faulty gear conditions which demonstrate the feasibility of using resonance demodulation based MCSA for monitoring of mechanical faults such as those arising from gearboxes.

The addition of ionic liquids with MXene nanofluid has a substantial impact on the solar thermal collectors’ working fluid’s optical properties that effectively absorb and distribute solar radiation. Increased solar radiation absorption potential ensures that heats are transported more rapidly and effectively. This research endeavors to investigate the concept of accumulating solar energy via the usage of ionic liquid-based 2D MXene nanofluid (Ionanofluids) for solar applications. In this study, the optical potential of Diethylene Glycol/MXene nanofluid incorporated with 1-ethyl-3-methyl imidazolium octyl sulfate ([Emim][OSO4]) ionic liquid was extensively investigated with respect to MXene concentration (0.1 to 0.4 wt%) and time (first day and seventh day) through UV-Vis Spectroscopy. A two-step approach was employed to synthesize the proposed ionanofluids with nanoparticle concentrations from 0.1 to 0.4 wt%. In wavelengths between 240 to 790 nm, the effect of ionic liquids, MXene ...