This research is focused on energy harvesting from track vibration in order to provide power for the wireless sensors which monitor railroad health. Considering that has energy, a new method proposed paper harvest based piezoelectric effect. The generator called drum transducer key part harvesting. model of established and simulation results show it can generate 100 mW real situation. In addition, an experiment rig developed its also established. peak open-circuit voltage about 50–70 V at...

Haptic-based tissue stiffness perception is essential for palpation training system, which can provide the surgeon haptic cues improving diagnostic abilities. However, current devices, such as Geomagic Touch, fail to immersive and natural interaction in virtual surgery due inherent mechanical friction, inertia, limited workspace flawed feedback. To tackle this issue, we design a novel magnetic levitation device based on electromagnetic principles augment environment. Users naturally interact...

Abstract The key dimensions of train wheelsets change with the increase running time. To ensure safe operation train, should meet relevant technical requirements. Maintenance and measurement are important part daily maintenance work. A rapid method based on image processing algorithms for hand-held integrating multiple parameter measurements is studied. general framework system examined roles modules described. optical center initial position continuous line spot searched. extraction...

Two novel nonparametric identification approaches are proposed for piezoelectric mechanical systems. The novelty of the is using not only signals but also electric signals. expressions unknown and terms given based on Hilbert transform. decomposed re-assembled to obtain smooth stiffness damping curves. current mapping approach developed identify accurately a system with strongly nonlinear terms. successfully implemented simulate obtained from different systems, including Duffing...

The vibration energy of the track slab can be converted into electric for wireless sensors by piezoelectric harvesters. A laminated circular plate harvester (TLCP harvester) is designed in this paper based on foundation excitation. central frequency 222 Hz, which matched with 222.8 Hz slab. stiffness curve, damping, equivalent capacitance, and electromechanical coupling coefficient are obtained through experiment. harmonic balance method Runge–Kutta's voltage results consistent experimental...

In this paper, a new onboard energy storage system (ESS) is designed. addition, the experiment developed for recovery of metro vehicle braking. The proposed ESS not connected to DC bus, but brake chopper in inverter. has simple structure and high reliability due its independence from traction system, it does feedback system. mathematical model dynamics was studied. A scaled simulate conditions test characteristics ESS. whole modeled simulated Matlab/Simulink software. results show that...

Segmentation of the left ventricle (LV) is essential for quantitative calculation clinical indices analyzing cardiac contractile function. However, it challenging to automatically segment small-contour magnetic resonance (CMR) images traditional convolutional neural networks (ConvNets) because their low robustness scale variation. In this paper, we propose a multi-scale fusion learning method advance performance ConvNets LV segmentation. To realize our learning, single-scale input and output...

To harvest acoustic energy from urban railways, a novel and practical harvester is developed. The consists of piezoelectric circular plate Helmholtz resonator. Based on the field test data resonance frequencies resonator are near 800 Hz. designed to amplify sound pressure. Thus, lumped parameter model established. used convert mechanical into electrical energy. simulation results show that output power approximately 25 μ W maximum voltage 0.149 V under excitation railway noise. experiment...

The effect of aerodynamic noise from high-speed trains on residents living near railway lines is a critical issue. pantograph cavity considered to be major source noise. To address this problem, study proposes the application jetting at leading edge cavity, directly targeting reduction its source. large eddy simulation approach used for flow calculations, and Ffowcs Williams Hawkings aeroacoustic analogy adopted far-field acoustic predictions. Orthogonal designs backpropagation algorithm...

A piezoelectric energy harvester is investigated with the focus on its nonlinear behavior. The core of a circular composite plate. lumped parameter model established parameters identified from experimental data. fifth polynomial employed to approximate restoring force. harvesting system theoretically studied by harmonic balance method arc-length continuation and solutions are supported time-domain numerical simulations experiment results. results display that amplitude-frequency response has...

In this paper, the energy distribution of electrical braking for an urban railway transportation system is studied. order to calculate percentage regenerative and resistance energy, line 2 Shanghai Metro traction power network modeled through analysis approach. An effective method proposed establish equivalent models each part network. The parameters conditions are based on real from 2. When departure interval 200 seconds, accounts 71.8% total simulation data 69.3% measured data. This paper...

As the main noise source of high-speed train, aerodynamic has a great influence on surrounding environment and ride comfort, which thorough understanding should be obtained. In this paper, fluid wave equation is constituted based dynamics theory generation mechanism analyzed. Then, three-dimensional physical model train established, steady flow field around simulated. Finally, surface calculated. The results show that dipole dominant pressure fluctuation root cause noise. sound power level...

Compared with the standard extraction interface circuit (SEH), harvested energy and power of synchronized switching harvesting circuits (SSHI) synchronous charge (SECE) cannot improve more effectively. This article proposes a bias-voltage-SSHI (BV-SSHI), consisting single peak voltage detection switch rectifier, to solve this problem. The proposed BV-SSHI improves output by biasing piezoelectric harvester obtains similar as SSHI. Simulation results show that can obtain than SEH under weak,...