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C.Donciu, O.Costea
VISION BASED INTELLIGENT SEMAPHORING SYSTEM

The present paper suggest making an intelligent video system of command over crossroads with traffic lights, its main goal being to diminish of traffic congestions, to improve vehicle speed, to reduce environment pollution and to improve negative effects of traffic congestion over the physic and psychic state of the population. The architecture of the suggested system is made on a hardware level from three different areas: the video sensor’s level, the computer process level and the represented execution level and the traffic-lights that exist in the crossroad. The software architecture of this system is made out of the main routine and a number of secondary routines of image processing and of the Fuzzy command. The existing systems are useful only in low traffic crossroads, being able to interpret informations only from the near proximity of the sensors, but unable to estimate the number of vehicles waiting in line on a traffic lane.

Biserka Mladinic, Tijana Parlic-Risovic
ADDITIONAL CONTROL OF AMBIENT CONDITIONS IN MASS METROLOGY AND ITS INFLUENCE ON MEASUREMENT QUALITY

Mass determination by use of mass comparators is influenced by different parameters including the conditions of ambient air. Having a look at the temperature of weights and the gravitational field gradients, the relatively small impact of these parameters on mass determination can be easily determined on the base of reproducible measurement results. Of metrological interest is the air density determination and control during a measurement series that could be used to improve the quality of measurement. The influence of temperature change as a function of time and its control simultaneously during the weighting process is discussed. The implementation and use of small climate chambers around the mass comparators to smooth out the temperature and relative moisture variations is described and discussed.

Paul Hohmann
CONCEPT OF A TORQUE CALIBRATION UNIT FOR LOW RANGES BASED ON AIR BEARING COMBINATION

The need to calibrate torque in low ranges is given in case of dentist tools, viscometry or friction measurement in ball bearings. Ranges starting about 0,005 N·m as an example, is the target of the following description. A theoretic possibility is shown how to handle all disturbing influences in using mass beam systems as a basic quantity.

Aimo Pusa
TRACEABILITY OF THE CALIBRATION OF TEST CAR FOR ROLL BRAKE TESTER

The calibration of the roll brake tester for trucks has been made general by direct loading of the force transducer. That means to ignore the complete force transmission to rollers, which are in contact to trucks wheel. To be able calibrate exactly the braking force the Finnish institute YTOL has developed a test car to measure direct this braking force. The car has an extra axle with free rotating wheels and braking equipments as well the torque measuring devices. The axle can be moved in vertical position to have the weight maximum 4000 kg on the axle. Raute-MIKES had the task to realise the calibration of this measurement device. The calibration has been made with a 20 kN·m reference torque transducer, which is calibrated static by PTB. The calibration of the brake measurement system has been made as dynamic with the speed of braking as static.

C. Dogan, O. Akkoyunlu, C. Kuzu
DEVELOPMENT OF THE 1 kN·m STATIC TORQUE STANDARD MACHINE AT UME

In the last decade, the increase in the need for the accuracy of the torque metrology created an obligation to produce a new torque standard machine for precise measurement of torque. This paper summarizes the torque standard machine designed and manufactured at UME with the range from 2 N·m up to 1 kN·m. In this machine torque is realized by a lever-mass system. Nominal force arm length of the lever is 0.5 m and constant. In each side of the lever, there are 6 different weight sets; and each set is containing 13 individual mass-stacks. For minimizing the torque loss at fulcrum an aerostatic bearing is used, and the change in the lever position due to the dead weights loading is corrected.

Jong-Ryeol Noh, Jae-Young Jeon
DEVELOPMENT AND EVALUATION OF 6-COMPONENT LOAD CELL FOR LAND-BASED TEST OF HELICOPTER ROTOR DYNAMICS

A 6-component force transducer was developed and evaluated for small-scale model test of helicopter rotor dynamics. The evaluation of the transducer was done mainly through interference check using multi-component calibration procedures. In this paper, the design and analysis process and the related results are verified through calibration results. The force transducer was designed to fix to rotating hub, and dominant force component was lifting force with maximum 1000 lb. From rotating characteristics, fail-safe structure was required to prevent the rotor from bursting out in case of rotor failure. The sensing element was designed with structural symmetry for selfcompensation by full bridge circuit and the expected deformation was analyzed by using finite element method.

Yon-Kyu Park, Rolf Kumme, Dae-Im Kang
DYNAMIC INVESTIGATION OF MULTI-COMPONENT FORCE SENSORS USING HARMONIC EXCITATION

This paper describes the dynamic investigation of a 3-component and a 6-component forcemoment sensors using the facilities in the PTB (Physikalisch-Technische Bundesanstalt) in Germany. The 3-component sensor has the transverse forces Fx and Fy of each having 200 N capacity and a twisting moment Mz of 10 N·m capacity and the 6-component sensor has force components Fx, Fy and Fz each having 200 N capacity and moment components Mx, My and Mz each having 20 Nm capacity. The sensitivity of the sensors decreases as the frequency increases and the sensors show almost 90o symmetry due to their geometry.

Jorge C. Torres-Guzmán, Amritlal Sawla, Daniel Ramírez-Ahedo
FORCE STANDARDS COMPARISON BETWEEN PTB (GERMANY) AND CENAM (MEXICO)

A force comparison was carried out between the Centro Nacional de Metrología, CENAM (in Mexico) and the Physikalisch-Technische Bundesanstalt, PTB (in Germany), in order to estimate the level of agreement for the realization of the quantity and the uncertainty associated to its measurement. The comparison was carried out in a range starting at 2 kN and up to 150 kN. In order to achieve best accuracy of the force transducers used was made of 5 sub ranges (5 kN, 20 kN, 50 kN, 100 kN and 150 kN). The results obtained, the deviations graphs that include the uncertainty for each laboratory are presented in this document.

Heikki Kajastie, Jorma Manninen, Kari Riski
DENSITY CALIBRATIONS AT MIKES

The density measurement instruments at MIKES will be described. Also a construction of a instrument for weights 1 g – 200 g will be presented. The main test results will be given.

Željko Alar, Mladen Franz
TRACEABILITY IN FORCE MEASUREMENT IN REPUBLIC OF CROATIA

In this study, based on results of the previously performed calibrations and factory specifications, an analysis of force measurement equipment in Republic of Croatia has been done. Transfer force standards of the Laboratory for Testing Mechanical Properties ( LIMS) have been calibrated in HBM, Germany. Calibration curves for specific transfer standards were obtained, to be used for estimation of standard uncertainties. Also, expanded measurement uncertainty was calculated at each measuring point, according to the document EA-4/15. This was used for determining the best measuring capability of the Laboratory, as well as for developing of the equipment calibration scheme for force measurement in Croatia. The previous and last calibration results for the same transfer standards were compared and, further to it, certain conclusions were made on how characteristics of the standards are influenced by use during certain period of time.

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