The Driving Severity Number (DSN) — A Step Toward Quantifying Treadwear Test Conditions

1986 ◽  
Vol 14 (3) ◽  
pp. 139-159 ◽  
Author(s):  
A. G. Veith
Keyword(s):  
Signal Processing ◽  
Ambient Temperature ◽  
Lateral Acceleration ◽  
Force Distribution ◽  
Single Index ◽  
Tire Force ◽  
Test Conditions ◽  
Wheel Revolution ◽  
High Degree ◽  
Revolution Counter

Abstract A system, called the “Driving Severity Monitor” (DSM), has been developed for characterizing tire force distribution as related to treadwear in either normal tire use or in tire fleet testing in a convoy. The system consists of an accelerometer for monitoring lateral accelerations, a wheel revolution counter, and a module for signal processing and read-out. The output of the DSM is reduced to a single index, the Driving Severity Number (DSN), which characterizes a vehicle journey. The DSN is equal to the sum of squares of lateral acceleration measured once per tire revolution during a trip, divided by the number of wheel revolutions. The DSN had a high degree of correlation (R ≧ 0.95) with treadwear in two wear programs when pavement abrasiveness was held constant. This supports the concept that the three basic treadwear components: tire force distribution, pavement abrasiveness, and ambient temperature, can be separated for better understanding of tire treadwear.

Simultaneous Optimal Distribution of Lateral and Longitudinal Tire Forces for the Model Following Control

2004 ◽  
Vol 126 (4) ◽  
pp. 753-763 ◽  
Author(s):  
Ossama Mokhiamar ◽  
Masato Abe
Keyword(s):  
Lateral Force ◽  
Longitudinal Force ◽  
Equality Constraints ◽  
Steering Wheel ◽  
Slip Angle ◽  
Force Distribution ◽  
Distribution Method ◽  
Tire Force ◽  
Model Following Control ◽  
Tire Forces

This paper presents a proposed optimum tire force distribution method in order to optimize tire usage and find out how the tires should share longitudinal and lateral forces to achieve a target vehicle response under the assumption that all four wheels can be independently steered, driven, and braked. The inputs to the optimization process are the driver’s commands (steering wheel angle, accelerator pedal pressure, and foot brake pressure), while the outputs are lateral and longitudinal forces on all four wheels. Lateral and longitudinal tire forces cannot be chosen arbitrarily, they have to satisfy certain specified equality constraints. The equality constraints are related to the required total longitudinal force, total lateral force, and total yaw moment. The total lateral force and total moment required are introduced using the model responses of side-slip angle and yaw rate while the total longitudinal force is computed according to driver’s command (traction or braking). A computer simulation of a closed-loop driver-vehicle system subjected to evasive lane change with braking is used to prove the significant effects of the proposed optimal tire force distribution method on improving the limit handling performance. The robustness of the vehicle motion with the proposed control against the coefficient of friction variation as well as the effect of steering wheel angle amplitude is discussed.

scholarly journals Alternative digital filltering scheme for LumiCal read-out

2019 ◽  
Vol 201 ◽  
pp. 04004
Author(s):  
Evgenii Lutsenko
Keyword(s):  
Signal Processing ◽  
Electromagnetic Calorimeter ◽  
Beam Test ◽  
Forward Region ◽  
Test Beam ◽  
Test Conditions ◽  
Electron Positron

The LumiCal electromagnetic calorimeter is designed for the forward region of future electron-positron colliders, such as CLIC and ILC. It is intended to improve hermeticity of detectors by detecting electrons, positrons, and photons at small angles. Currently, the detector prototypes are studied in the beam test conditions. An important part of the signal processing is the digital filltering implemented in the read-out electronics, influencing the precision and quality of gathered data. In this article two schemes of digital filltering of gathered signal from test beam for the LumiCal detector prototype are presented.

Recycling Scrap Crosslinked Urethane Polymers

1975 ◽  
Vol 48 (5) ◽  
pp. 972-980 ◽  
Author(s):  
R. M. Gerkin ◽  
F. E. Critchfield ◽  
W. A. Miller ◽  
R. Roberts ◽  
C. G. Seefried
Keyword(s):  
Particle Size ◽  
Ambient Temperature ◽  
Size Reduction ◽  
Minor Effect ◽  
Particle Size Reduction ◽  
Foam Formulation ◽  
A Minor ◽  
High Degree ◽  
Sulfur Curing

Abstract A. Scrap LRM polymers can be ground to powder on the Banbury operating at ambient temperature with cooling of the rotors and jacket. Particle size reduction can be accomplished in 5 min at 180 rpm. B. Powdered LRM polymer can be blended with TPU up to 50 wt.% and the composite compression molded to give the same properties as the TPU. C. Powdered LRM polymer can be blended with nitrile, chloroprene, and EPDM rubbers to give incompatible composites. The powdered LRM polymer acts in a manner similar to typical nonreinforcing fillers. D. It is possible to degrade powdered LRM polymers to a tacky mass at 180°C, which behaves much like a typical extender oil, when blended with nitrile and chloroprene rubbers. It is speculated that the degraded urethane should show a high degree of permanency in such blends. E. Addition of the urethane polymer to the rubber stocks does not interfere with the standard sulfur-curing mechanisms. F. Scrap HR foam can be ground to a powder in the Banbury in a manner similar to LRM scrap. G. A blend of 5 phr of powdered foam with a new HR foam formulation was machine processable. Addition of the powder had only a minor effect on the properties of the new foam.

Soft Synthesis of FAU Nanozeolites and Microporous Membranes

2014 ◽  
Vol 87 ◽  
pp. 24-29
Author(s):  
Teresa Fina Mastropietro ◽  
Enrico Drioli ◽  
Teresa Poerio
Keyword(s):  
Ambient Temperature ◽  
Industrial Applications ◽  
High Yield ◽  
Sem Images ◽  
Ceramic Substrates ◽  
Dry Gel Conversion ◽  
Gel Layer ◽  
High Degree ◽  
Uniform Particle Size ◽  
Tubular Alumina

An alternative strategy to the conventional seeded-assisted synthesis of Faujasite (FAU) nanozeolites and their assembling into thin films on ceramic substrates are reported. The method, which can be easily extended to other zeolite topologies, offers good opportunities for industrial applications. The molar composition of the precursor gel used for the synthesis of FAU nanozeolites and membranes was conceived to achieve a high degree of supersaturation and trigger a uniform and abundant nucleation. Tubular alumina supports seeded with NaX particles of 2μm have been used to address the crystallization process. The synthesis was carried out in “soft condition” at near ambient temperature (30°C). Pure-phase FAU zeolites having uniform particle size dimensions in the range of 35-56 nm have been produced in high yield. Moreover, a uniform gel layer containing precursor entities has been concomitantly formed on the inner surface of the support after immersion in the synthesis gel. Thin and dense FAU membranes have been prepared through dry-gel conversion at higher temperatures. SEM images showed that the FAU layers have a thickness of ca. 2 μm and are constituted by closely packed, well intergrown nanocrystals, whose dimension was ca. 20-30 nm. The mass transport properties of the prepared membranes were probed by feeding dry single gases (N2 and CO2) at ambient temperature, obtaining low permeance (ca. 3.8·10-9 molm-2s-1Pa-1 for N2) and ideal selectivity higher than the corresponding Knudsen value.

Theoretical Research on Ideal Brake Force Distribution of Tractor-Semitrailer Cornering Braking

2013 ◽  
Vol 467 ◽  
pp. 451-455
Author(s):  
Chen Li ◽  
Xing Hu Li ◽  
Wei Zhou ◽  
Wei Liang Dai
Keyword(s):  
Load Transfer ◽  
Lateral Acceleration ◽  
Theoretical Research ◽  
Force Distribution ◽  
Vertical Load ◽  
Traditional Design ◽  
Brake Force ◽  
Braking Control ◽  
Brake Force Distribution ◽  
The Ideal

For tractor-semitrailer, load transfer during cornering braking caused big difference of the vertical load between coaxial wheels. As a result, braking efficiency and directional stability were affected seriously, the traditional design of braking force distribution between axles couldnt meet the requirements. In this paper, a dynamic model of tractor-semitrailer was established according to the motion and force during cornering braking. The rule of vertical load changing of each wheel with longitudinal acceleration and lateral acceleration was obtained. Combining with the tire and road adhesion conditions, the ideal brake force distribution was achieved. The research could provide theoretical reference to better control strategy of tractor-semitrailer braking control system.

scholarly journals Conflict and Sensitivity Analysis of Vehicular Stability Using a Two-State Linear Bicycle Model

2021 ◽  
Vol 2021 ◽  
pp. 1-17
Author(s):  
Mohamed A. Hassan ◽  
Mohamed A. A. Abdelkareem ◽  
Gangfeng Tan ◽  
M. M. Moheyeldein
Keyword(s):  
Critical Role ◽  
Lateral Acceleration ◽  
Vehicle Stability ◽  
Vehicle Speed ◽  
Sideslip Angle ◽  
Tire Force ◽  
Operation Conditions ◽  
Bicycle Model ◽  
Tire Stiffness ◽  
Longitudinal Position

Vehicle parameters and operation conditions play a critical role in vehicular handling and stability. This study aimed to evaluate vehicle stability based on cornering tire stiffness integrated with vehicle parameters. A passenger vehicle is considered in which a two-state linear bicycle model is developed in the Matlab/Simulink. The effect of the vehicle parameters on lateral vehicle stability has been investigated and analyzed. The investigated parameters included CG longitudinal position, wheelbase, and tire cornering stiffness. Furthermore, the effects of load variation and vehicle speed were addressed. Based on a Fishhook steering maneuver, the lateral stability criteria represented in lateral acceleration, yaw rate, vehicle sideslip angle, tire sideslip angles, and the lateral tire force were analyzed. The results demonstrated that the parameters that affect the lateral vehicle stability the most are the cornering stiffness coefficient and the CG longitudinal location. The findings also indicated a positive correlation between vehicle properties and lateral handling and stability.

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