Underwater Dynamic Response at Limited Points Expanded to Full-Field Strain Response

Expansion of measured dynamic response at a limited set of points is of great interest in the study of structural dynamic systems. Measurements at limited points on a structure can be expanded to unmeasured points by using System Equivalent Reduction Expansion Process (SEREP). However, a finite element model is required to obtain the mode shapes of the system. In this work, a non-model based expansion technique is proposed to expand the vibration characteristics at a sparse set of points to a much larger set of points without the use of a finite element model. Shape functions based on orthogonal polynomials can be used to decompose the deformation of vibrating structures into the summation of a set of shape functions with corresponding weighting coefficients. To obtain the vibration characteristics at an augmented set of points, measurements at a sparse set of points can be related to a set of shape functions which have the same mesh resolution as the sparse configuration. The vibration characteristics at an augmented set of points can then be reconstructed from the shape functions of the high resolution and scaled shape function weighting coefficients of the sparse configuration. Only a sparse set of measurements, geometry and coordinates of measured points are needed. In the work studied here, an analytical plate and a Base-Upright (BU) structure are used as samples to study the application of the proposed method. Both analysis and experiment are used to prove the concept.

Non-Model Based Expansion from Limited Points to an Augmented Set of Points Using Chebyshev Polynomials

The trade-off between handling stability and ride comfort is a disadvantage for the bus fitted with passive suspension due to its high center of gravity and heavy load. A novel suspension configura...

Improvement of both handling stability and ride comfort of a vehicle via coupled hydraulically interconnected suspension and electronic controlled air spring

Instability caused by emergency braking and steering during ambulance operation would easily lead to a sharp rise of blood pressure in patient’s head, which would further cause a secondary injury t...

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Improvement of ride quality for patient lying in ambulance with a new hydro-pneumatic suspension

A frequency-based modeling approach has been developed for the vehicle fitted with Hydraulically Interconnected Suspension (HIS) system. This frequency-based model has fewer degrees of freedom (DOF) than the reference time-based model. Several physical parameters of HIS system are selected to analytically investigate their effects on several indicators of vehicle roll, pitch and bounce modes, such as roll and pitch angular acceleration, vertical acceleration, and tire ground force. The HIS system parameters are also coordinately tuned and optimized to meet the ride comfort requirement. The full vehicle drop test is conducted for the experimental validation. The analytical results of the proposed model have a good agreement with the measurements.

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Frequency-Based Modeling of a Vehicle Fitted With Roll-Plane Hydraulically Interconnected Suspension for Ride Comfort and Experimental Validation

A new physical parameter identification method for two-axis on-road vehicle is presented. The modal parameters of vehicle are identified by using the State Variable Method. To make it possible to determine the matrices , , and of the vehicle, a known mass matrix is designed to add into the vehicle in order to increase the number of equations ensuring that the number of equations is more than the one of unknowns. Therefore, the physical parameters of vehicle can be estimated by using the least square method. To validate the presented method, a numerical simulation example and an experiment example are given in this paper. The numerical simulation example shows that the largest of absolute value of percentage error is 1.493%. In the experiment example, a school bus is employed in study for the parameter identification. The simulation result from full-car model with the estimated physical parameters is compared with the test result. The agreement between the simulation and the test proves the effectiveness of the proposed estimation method.

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A New Physical Parameter Identification Method for Two-Axis On-Road Vehicles: Simulation and Experiment

The utility model relates to the technical field of automobile performance test technologies and specifically relates to a fatigue test system for a vehicle hydraulic interconnection suspension rack system The fatigue test system comprises a pedestal, a drive mechanism and a controller, wherein the pedestal is used for arranging all hydraulic cylinders of the vehicle hydraulic interconnection suspension rack system, the drive mechanism is used for driving all the hydraulic cylinders to synchronously compress and stretch, and the controller is used for controlling operation of the drive mechanism According to the fatigue test system for the vehicle hydraulic interconnection suspension rack system, the drive mechanism drives all the hydraulic cylinders of the hydraulic interconnection suspension rack system to synchronously compress and stretch, and the whole hydraulic interconnection suspension rack system is an integral body in fatigue test processes; compared with a fatigue test device of the prior art, the test system is advantageous in that test results are trustable and reliable, the performance of the vehicle hydraulic interconnection suspension rack system can be truly reflected, and improvement of the quality and the safety of a tested vehicle hydraulic interconnection suspension rack system can be facilitated

Fatigue test system for vehicle hydraulic interconnection suspension rack system

The utility model discloses an early warning device of an oil and gas suspension system The early warning device comprises a pressure sensor, a controller and an alarm, wherein the pressure sensor is arranged in a pressure medium loop of the oil and gas suspension system; the signal input end of the controller is electrically connected with the output end of the pressure sensor; the signal input end of the alarm is electrically connected to the signal output end of a single chip microcomputer The utility model further provides the oil and gas suspension system and a motor vehicle By means of the oil and gas suspension system, the early warning device of the oil and gas suspension system and the motor vehicle, vehicle safety is improved to a certain degree

Oil and gas suspension system, early warning device thereof and motor vehicle

Battery energy storage systems (BESSs) alleviate the renewable energy generation intermittency and can also realize revenue through participation in multiple applications, including energy arbitrage and ancillary services. This paper investigates cost effectiveness of behind-the-meter BESSs to reduce system costs and provide frequency regulation service. The BESS is modeled to support different operational modes, including energy arbitrage and frequency regulation service, either one at a time or concurrently. To evaluate the cost effectiveness of the BESS in various operational modes, we conduct simulations based on existing rules of Singapore's electricity market for behind-the-meter BESSs. Our simulation results show that BESSs' multi-application, in general, can reduce the system cost. In Singapore context, the resulting cost reduction becomes limited due to the existing metering rules.

Multi-Application Battery Energy Storage Systems for Energy Arbitrage and Frequency Regulation: Singapore Context Analysis

We propose a two-stage model predictive control (MPC) based optimization framework to enable regulation market participation for battery energy storage systems (BESSs). Specifically, the first stage of the optimization, named “Stage-A”, aims to compute optimal charging and discharging power references for the BESS. The second stage, named “Stage-B”, aims to track the regulation signal closely, while working in conjunction with Stage-A. The proposed framework can be readily extended to multiple number of BESSs and can be also configured to support different regulation market models. We consider Singapore regulation market as a case study and show that the model can strictly abide by market rules of state of charge (SOC) based basepoint setting and prevention of reverse behavior, while following the regulation signal closely.

Peng Peng

Papers

A New Physical Parameter Identification Method for Two-Axis On-Road Vehicles: Simulation and Experiment

Fatigue test system for vehicle hydraulic interconnection suspension rack system

Oil and gas suspension system, early warning device thereof and motor vehicle

Multi-Application Battery Energy Storage Systems for Energy Arbitrage and Frequency Regulation: Singapore Context Analysis

Two-Stage Optimization Framework for Battery Energy Storage System Co-Optimization in Regulation Market