A Driver’s Seat With Active Suspension of Electro-pneumatic Type

1997 ◽  
Vol 119 (2) ◽  
pp. 230-235 ◽  
Author(s):  
G. J. Stein
Keyword(s):  
Mathematical Description ◽  
Active Suspension ◽  
Full Scale ◽  
Experimental Results ◽  
Pneumatic Suspension ◽  
Pneumatic Transducer ◽  
Short Explanation

The aim of this article is to summarize some of the results of a study of a driver’s seat with an electro-pneumatic active suspension utilizing a pneumatic spring and a proportional electro-pneumatic transducer. Discussion of the system’s simplified mathematical description is followed by a short explanation of the full scale dummy driver’s seat with active pneumatic suspension and discussion of some experimental results.

Experimental results of an ∞-observer for an industrial semi-active suspension

2010 ◽  
Vol 43 (7) ◽  
pp. 318-323 ◽  
Author(s):  
S. Aubouet ◽  
L. Dugard ◽  
O. Sename
Keyword(s):  
Active Suspension ◽  
Experimental Results

A COMPARATIVE STUDY OF PHENOMENOLOGICAL MODELS OF MR BRAKE BASED ON NEURAL NETWORKS APPROACH

2013 ◽  
Vol 11 (01) ◽  
pp. 1350009 ◽  
Author(s):  
WITOLD PAWLUS ◽  
HAMID REZA KARIMI
Keyword(s):  
Neural Networks ◽  
Vibration Suppression ◽  
Feedforward Neural Networks ◽  
Active Suspension ◽  
Full Scale ◽  
Parameters Estimation ◽  
Model Parameters ◽  
Systems Identification ◽  
Active Vibration ◽  
Models Validation

In this paper a full-scale commercially available magnetorheological (MR) brake installed in a semi-active suspension (SAS) system is modeled and simulated. Two well-known phenomenological hysteresis models are explored: Bouc–Wen and Dahl ones. In particular, influence of their parameters on the response is evaluated and assessed. The next step is to introduce the artificial neural networks and discuss their application in the field of systems identification. Subsequently, two feedforward neural networks are created and trained to estimate parameters characterizing each of the MR damper models described. The semi-active suspension (SAS) system equipped with a MR brake is described and the detailed procedure for acquisition of the reference data used in the models validation stage is elaborated. The models outputs obtained by simulating them with the values of coefficients as identified by the networks are compared to each other as well as to the reference experimental data. Thanks to that, the comparative analysis between the suggested vibration suppression models and the full-scale MR brake is done and it is concluded which of the discussed models has a better performance. The usability of neural networks in the field of parameters estimation of the mathematical models of the real world phenomena is described as well. The novelty of the presented methodology is the application of artificial intelligence methods to estimate model parameters of a MR brake utilized in a SAS system. The results of this approach have a strong potential to be successfully implemented in the area of model-based control of semi-active vibration suppression systems.

Modal Strain Energy Based Damage Detection Applied to a Full Scale Composite Helicopter Blade

2013 ◽  
Vol 569-570 ◽  
pp. 457-464 ◽  
Author(s):  
Fabio Luis Marques dos Santos ◽  
Bart Peeters ◽  
Herman van der Auweraer ◽  
Luiz Carlos Sandoval Góes
Keyword(s):  
Structural Health Monitoring ◽  
Damage Detection ◽  
Health Monitoring ◽  
Rotor Blade ◽  
Strain Energy ◽  
Full Scale ◽  
Experimental Results ◽  
Main Rotor ◽  
Helicopter Blade ◽  
Main Rotor Blade

The use of composites in the aircraft industry has generated a great need for structural health monitoring and damage detection systems, to allow for safer use of complex materials. Such is the case with helicopter blades - these components nowadays are mostly composed of carbon fiber or glass fiber reinforced plastics laminates, epoxy and honeycomb filled core structures. The use of composite materials on the main rotor blade also allows for more complex and efficient shapes to be designed, but at the same time, their use requires an additional effort when it comes to structural monitoring, since damage can occur and go unnoticed. This work presents experimental results for structural health monitoring method based on strain energy. The test subject is a full-scale composite helicopter main rotor blade, which is a highly flexible, slender beam that can display unusual dynamic behavior with orthotropic behavior. This damage detection method is based on the modal strain properties, and a damage detection index is used to identify and quantify damage. A test setup was built to carry out an experimental modal analysis on the main rotor blade. For that purpose, a total of 55 uniaxial accelerometers were used on the helicopter blade to measure the displacement modes of the structure. To compute the strain modes from the displacement modes, central differences approximation is used. Damage is introduced on the blade by attaching a small mass to two different locations. Experimental results show the possibility of locating damage in this case.

Some Experimental Results on Internal Fire Whirls in a Vertical Shaft

2013 ◽  
Author(s):  
Y. Gao ◽  
G. W. Zou ◽  
S. S. Li ◽  
W. K. Chow
Keyword(s):  
Full Scale ◽  
Pool Fire ◽  
Experimental Results ◽  
Vertical Shaft ◽  
Remote Site ◽  
Scale Modeling ◽  
Key Factor ◽  
Fire Whirl ◽  
Real Scale

Earlier studies on burning a pool fire in a vertical shaft model indicated that appropriate sidewall ventilation provision is a key factor for the onset of an internal fire whirl. Experiments on burning a pool fire inside a real-scale shaft model of 9 m tall were performed to further investigate the swirling motion. The full-scale modeling burning tests were carried out at a remote site in China. Four different ventilation openings were arranged. Results of onsetting of internal fire whirls for the four tests will be reported.

Experimental Study on Full-Scale Segment Model of Huaian Cable-Stayed Bridge Pylon

2011 ◽  
Vol 243-249 ◽  
pp. 1866-1870 ◽  
Author(s):  
Hong Yuan Tang ◽  
Shao Ping Meng
Keyword(s):  
Experimental Study ◽  
Stress Distribution ◽  
Theoretical Analysis ◽  
Full Scale ◽  
Experimental Results ◽  
Horizontal Load ◽  
Experiment Study ◽  
Segment Model ◽  
Cable Stayed Bridge

Through experiment study on full scale segmental model of Huaian bridge pylon, the stress distribution in the segmental model under the U shaped tendons and the horizontal load was measured. At the same time, the critical cracking load and the coefficient cracking safety class of the anchorage zone were obtained. At last, the theoretical analysis was compared with the experimental results, the theory agreed with the experiment well.

EVALUATION OF DISCRETE ADAPTIVE FAIL-SAFE ACTIVE SUSPENSION

1997 ◽  
Vol 21 (3) ◽  
pp. 205-220 ◽  
Author(s):  
R.V. Dukkipati ◽  
S.S. Vallurupalli ◽  
M.O.M. Osman
Keyword(s):  
Adaptive Control ◽  
Active Suspension ◽  
Full Scale ◽  
Least Square ◽  
Recursive Least Square ◽  
Single Degree Of Freedom ◽  
Computer Controlled ◽  
Fail Safe ◽  
Model Reference Adaptive ◽  
First Time

Hardware implementation of discrete adaptive control for a full scale vehicular single degree of freedom (SDOF) active suspension has been discussed in this paper. This paper describes an experimental evaluation of full scale fail-safe adaptive active (SDOF) suspension system that has been performed for the first time. A servo hydraulic force actuator is installed along with passive suspension components to form a fail-safe active suspension. A discrete model reference adaptive control (DMRAC) approach with recursive least square (RLS) estimation and covariance modification has been used for the software/hardware based digital control. A real time computer controlled adaptive active suspension software which shows the experimental response and animation of the results has been developed.

Numerical Simulation of the Added Mass of the Fluid Adjacent to the Ship Hull in Vibration Measured During Sea-Trials in Tanker Ships to be Converted to Offshore Construction Vessel

2012 ◽  
Author(s):  
Severino Fonseca Silva Neto ◽  
Silvia Ramscheid Figueiredo ◽  
Marta Cecilia Tapia Reyes ◽  
Luiza de Mesquita Ortiz
Keyword(s):  
Numerical Model ◽  
Kinetic Energy ◽  
Natural Frequencies ◽  
Three Dimensional ◽  
Added Mass ◽  
Vertical Vibration ◽  
Full Scale ◽  
Experimental Results ◽  
Vibration Velocity ◽  
Main Engine

This study aims to analyze the influence of the kinetic energy of the fluid adjacent to the hull of a tanker ship in its vertical vibration frequencies, comparing them with experimental measurements obtained during sea-trials. The one-dimensional modeling of ships allows the construction of simple finite element models from the structural elements of its master section, with structural and added masses, and their frequencies are verified by full-scale measurements, during the sea-trials. The numerical results of these models, with the value of the effective shear area as a fraction of the total area of the strength steel are compared to those obtained in full-scale measurements during sea trials of an oil tanker to be converted to Offshore Construction Vessel. Global vibration measurements were carried out in two of the six ships with the same hull. Accelerometers were installed in eleven strategic points of each hull. Vibration data acquisition was performed simultaneously for these locals in thirteen rotations of the main engine. The amplitude spectra of vibration velocity on the frequency range of measurements were obtained and were plotted graphs of the evolution of the main harmonics, depending on the rotation of the main engine, in order to identify four natural frequencies of the overall vibration of the hull, which were compared to the numerical model. The calculation is performed by the added mass formulations from Burrill, Todd, Kumay and Lewis/Landweber [8] curves, including in all three-dimensional effect by Townsin [17] coefficients, which is checked against the experimental results. The comparison between numerical and experimental results allows assessing the influence of the kinetic energy of the fluid surrounding the hull in the natural frequencies of vibration of the numerical model of the tanker ship and simulating their dynamic behavior after conversion in Offshore Construction Vessel.

Dynamic Characteristics of a Jetting Dispenser for Wafer Die Marking

2011 ◽  
Vol 52-54 ◽  
pp. 1713-1717
Author(s):  
Lue Zhang ◽  
Hong Hu ◽  
Yong Cao
Keyword(s):  
Numerical Simulations ◽  
Dynamic Characteristics ◽  
Mathematical Description ◽  
Droplet Generation ◽  
Experimental Results ◽  
Phase Flow ◽  
Key Factors ◽  
Intensive Production ◽  
Wafer Manufacturing

Ink marking is a key process for die sorting of IC wafer manufacturing. Intensive production of wafer is urging the inkers for more rapid and more stable ink marking performance on surface of defective wafer dies safely. In this paper, a non-contact jetting dispenser is introduced to the wafer die marking. After presenting the mathematical description of dynamic fluid for 2-phase flow, numerical simulations are launched to reveal the characteristics of droplet generation and key factors are discussed. A jetting dispenser is developed and experimental results are analyzed. According to the simulative results and the dotting performance shown in experiments, the non-contact jetting dispenser is capable for wafer die marking in dotting efficiency and stability.

Lab scale study on electrocoagulation defluoridation process optimization along with aluminium leaching in the process and comparison with full scale plant operation

2011 ◽  
Vol 63 (12) ◽  
pp. 2788-2795 ◽  
Author(s):  
Poonam Gwala ◽  
Subhash Andey ◽  
Vasant Mhaisalkar ◽  
Pawan Labhasetwar ◽  
Sarika Pimpalkar ◽  
...  
Keyword(s):  
Drinking Water ◽  
Process Optimization ◽  
Current Density ◽  
Fluoride Concentration ◽  
Full Scale ◽  
Experimental Results ◽  
Fluoride Removal ◽  
Electrode Polarization ◽  
Operational Conditions ◽  
Aluminium Leaching

An excess or lack of fluoride in drinking water is harmful to human health. Desirable and permissible standards of fluoride in drinking water are 1.0 and 1.5 mg/L, respectively, as per Indian drinking water quality standards i.e., BIS 10500, 1991. In this paper, the performance of an electro-coagulation defluoridation batch process with aluminium electrodes was investigated. Different operational conditions such as fluoride concentration in water, pH and current density were varied and performance of the process was examined. Influence of operational conditions on (i) electrode polarization phenomena, (ii) pH evolution during electrolysis and (iii) the amount of aluminium released (coagulant) was investigated. Removal by electrodes is primarily responsible for the high defluoridation efficiency and the adsorption by hydroxide aluminium floc provides secondary effect. Experimental data obtained at optimum conditions that favored simultaneous mixing and flotation confirmed that concentrations lower than 1 mg/L could be achieved when initial concentrations were between 2 and 20 mg/L. pH value was found to be an important parameter that affected fluoride removal significantly. The optimal initial pH range is between 6 and 7 at which effective defluoridation and removal efficiencies over 98% were achieved. Furthermore, experimental results prominently displayed that an increase in current density substantially reduces the treatment duration, but with increased residual aluminium level. The paper focuses on pilot scale defluoridation process optimization along with aluminium leaching and experimental results were compared with a full-scale plant having capacity of 600 liter per batch.

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