Research on the Online Initial Value Calibration Method for the Wheel Force Transducer

Some initial values of the wheel force transducer (WFT) change after being mounted in the vehicle. The traditional static calibration is inadequate to fully obtain these initial values. Aiming to this problem, an online initial value calibration method is proposed. The method does not require any additional calibration equipment or manual operation and just requires the vehicle mounted with the WFT to be driven on a flat road with constant speed. In this way, an initial value mode is constructed and then converted to an optimization problem. To solve this problem and acquire the right initial value, an improved Memetic framework based on particle swarm optimization (PSO) and Levenberg-Marquardt (LM) is adopted. To verify the effect of the proposed method, the real WFT data is used and the comparative test is carried out. The experiment result shows that the proposed method is superior to the traditional one and can improve the measurement accuracy effectively.

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Real-Time Signal Denoising Algorithm in Wheel Force Transducer

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.615.244 ◽

2014 ◽

Vol 615 ◽

pp. 244-247

Author(s):

Dong Wang ◽

Guo Yu Lin ◽

Wei Gong Zhang

Keyword(s):

Kalman Filter ◽

Real Time ◽

Extended Kalman Filter ◽

Unscented Kalman Filter ◽

Force Transducer ◽

Time Signal ◽

Signal Denoising ◽

Observation Function ◽

Simulation Results ◽

Wheel Force Transducer

The wheel force transducer (WFT) is used to measure dynamic wheel loads. Unlike other force sensors, WFT is rotating with the wheel. For this reason, the outputs and the inputs of the transducer are nonlinearly related, and traditional Kalman Filter is not suitable. In this paper, a new real-time filter algorithm utilizing Quadrature Kalman Filter (QKF) is proposed to solve this problem. In Quadrature Kalman Filter, Singer model is introduced to track the wheel force, and the observation function is established for WFT. The simulation results illustrate that the new filter outperforms the traditional Unscented Kalman Filter (UKF) and Extended Kalman Filter (EKF).

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FORCE CALIBRATION OF NANO UNIVERSAL TESTING MACHINE USING MILLIGRAM WEIGHTS

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194513600318 ◽

2013 ◽

Vol 24 ◽

pp. 1360031

Author(s):

CHUNG-LIN WU ◽

CHING-FEN TUAN

Keyword(s):

Force Measurement ◽

Testing Machine ◽

Calibration Method ◽

Force Transducer ◽

Force Measurements ◽

Universal Testing Machine ◽

Universal Testing ◽

Small Force ◽

Force Calibration ◽

Force Range

This paper presents an approach for calibrating the force transducer on the nano universal testing machine using milligram weights. Previous research on force calibration of such a system focused on the range from 10 mN to 200 mN, ignoring forces below 10 mN. The main purpose of this study is to analyze and calculate the uncertainty of force measurements within the range from 0.2 mN to 10 mN. The ABA calibration method in accordance with OIML R111-1 is adopted to determine the uncertainty in force measurement. The results indicate that the maximum relative uncertainty of force measurement is 7.0 × 10−3 with a 95% confidence level. The investigation can be used as the basis for evaluating measurement uncertainty of the system in small force range.

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Effect of Added Mass of Spindle Wheel Force Transducer on Vehicle Dynamic Response

10.4271/2012-01-0210 ◽

2012 ◽

Cited By ~ 5

Author(s):

Shawn S. You

Keyword(s):

Dynamic Response ◽

Added Mass ◽

Force Transducer ◽

Vehicle Dynamic ◽

Wheel Force Transducer

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Interactions between intracellular calcium and phosphate in intact mouse muscle during fatigue

Journal of Applied Physiology ◽

10.1152/japplphysiol.01404.2010 ◽

2011 ◽

Vol 111 (2) ◽

pp. 358-366 ◽

Cited By ~ 28

Author(s):

D. G. Allen ◽

E. Clugston ◽

Y. Petersen ◽

I. V. Röder ◽

B. Chapman ◽

...

Keyword(s):

Tibialis Anterior Muscle ◽

Complete Recovery ◽

Force Transducer ◽

Partial Recovery ◽

Initial Value ◽

Intact Mouse ◽

Mouse Muscle ◽

Intracellular Ca ◽

Intracellular Phosphate ◽

Distal Tendon

Fatigue was studied in intact tibialis anterior muscle of anesthetized mice. The distal tendon was detached and connected to a force transducer while blood flow continued normally. The muscle was stimulated with electrodes applied directly to the muscle surface and fatigued by repeated (1 per 4 s), brief (0.4 s), maximal (100-Hz stimulation frequency) tetani. Force declined monotonically to 49 ± 5% of the initial value with a half time of 36 ± 5 s and recovered to 86 ± 4% after 4 min. Intracellular phosphate concentration ([Pi]) was measured by 31P-NMR on perchloric acid extracts of muscles. [Pi] increased during fatigue from 7.6 ± 1.7 to 16.0 ± 1.6 mmol/kg muscle wet wt and returned to control during recovery. Intracellular Ca2+ was measured with cameleons whose plasmids had been transfected in the muscle 2 wk before the experiment. Yellow cameleon 2 was used to measure myoplasmic Ca2+, and D1ER was used to measure sarcoplasmic reticulum (SR) Ca2+. The myoplasmic Ca2+ during tetani declined steadily during the period of fatigue and showed complete recovery over 4 min. The SR Ca2+ also declined monotonically during fatigue and showed a partial recovery with rest. These results show that the initial phase of force decline is accompanied by a rise in [Pi] and a reduction in the tetanic myoplasmic Ca2+. We suggest that both changes contribute to the fatigue. A likely cause of the decline in tetanic myoplasmic Ca2+ is precipitation of CaPi in the SR.

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