Papers by Keyword: Error

Abstract: As with any measuring device, it is important to install and operate water meters that are calibrated within an acceptable international standard (ISO) and regulatory acceptable relative error, in accordance with the requirements of the international standard. The article deals with the issue of correct installation of measuring devices during operation and checking on high-precision equipment. Production In order to increase the technical level and meet people's needs, there is a need to use the latest modern measuring tools of equipment and technology in the economy and production. For this reason, it is important to provide citizens with new measuring devices and provide them with regular technical service in our country. It is necessary to create modern equipment and laboratories for checking measuring instruments. As the devices are used, their life ends after a certain period of time, and they need to be checked. A malfunctioning device leads to incorrect information, incorrect calculations and losses, depending on where it is used for its intended purpose. By checking the measuring devices in modern laboratories with high accuracy, removing the defect and re-using it after calibration, we get correct calculations, correct information exchange, and elimination of losses. For example, the correct installation of water measuring devices was also checked on the error determination stand, and the results of their errors at different values ​​were automatically displayed in the error curve table.

Abstract: Cylindrical grating angle sensor is a common angle measuring device with high precision. Due to the reflecting arc surface of the cylindrical grating the effects of relative displacement of graduation line and gap variation will interact. Significant residual errors still exist even with high precision cylindrical grating and multiple reading heads around the scale disc .In this paper, based on the principle of circumference closure, the principle of self-calibration is deduced and analyzed in detail. The calibration curve is obtained by obtaining the deviation between the certain position and an ideal position of the graduation line position in real time. A simple self-calibration method of cylindrical grating is acquired. It can calibrate random errors and system errors with time and improve the angle measurement accuracy. The method has the advantages of simple structure and strong maneuverability, and provides technical means for the miniaturization and high precision of cylindrical grating.

Abstract: The article dwells upon the results of study of theshape influence of size of load’s motion using the sigmoidal functions of traversingsingle obstacle on the arc with suppression of load’s oscillations to theaccuracy figure of the trajectory’s realization. The possibility of thereduction of the maximum and average error by means of the little changing of the value ofthe arc’s lateral deformation for a fixed traveling time is shown in thisarticle. The functional dependencies of the maximum and average errors oftrajectory implementation from corrected value of the maximum arc’sdisplacement of required load's trajectory in lateral side to bypass obstaclesand from increasing of corrected value of the maximum displacement of the arcare given too.

Abstract: The experimental researches presented in this paper are aimed to improve the manufacturing accuracy of a contouring machine together with an approach to eliminate the errors which lead to a less precise part after machining.In order to eliminate the errors, the machine's feed drives were tuned leading to a more precise part. In order to validate the proposed approach, the accuracy of the machine was tested before and after the tuning process.

Abstract: Error compensation is a key to reach the geometric accuracies required for high precision machine tools. To prevent errors from affecting the machining process, compensation values for the feed axes can be used. However, conventional feed axes can only compensate deviations in their feed directions. By controlling its integrated hydraulic guiding system, the feed axis presented in this paper is capable of compensating errors in all other degrees of freedom as well. Using a specifically developed program, ideal parameters for the compensation of errors in a realistic 3D-axis-system were calculated. The axis’ characteristics were examined on a test rig for different types of controllers and compared to those parameters. It could be shown that the presented highly integrated hydraulic feed axis is capable of compensating typical errors resulting from such a 3D-setup.

Abstract: Analyzing applications involving industrial robots, these can generally be classified into two categories. In the first category, the robot is used to position an object or a tool in its working space. In the second category, the robot is used for programmed and continuous movement of an object in the working space. These two categories of use of industrial robots determine two families of characteristics considered fundamental for the assessment of performance robots: pose characteristics and tracking path characteristics. The pose characteristics are generally expressed by the pose accuracy and pose repeatability (positioning and orientation). From this category is “distance accuracy”, whose analysis is the subject of this paper. The authors present a method for measuring and evaluating of this characteristic, through 3D triangulation with two digital theodolits. The experimental researches were made for a welding robot type Cloos-Romat. The presented case study validates the results of the experimental research, the method and the used algorithm.

Abstract: Errors was generate when use integral methods to calculate pyrolysis kinetic. It was analyzed by considered the effects of methods and reaction orders. A α-T curve was established for the error discussion depending on basic kenotic theory. For analysis methods, both single curve and multiple curve methods can obtain reliable activation energy values (≤3%), but the error of frequency factor was significant (up to 40%). Frequency factor is sensitive to intercept changing and is also to reaction order. Magnitude error could show if reaction order deviates to true value.

Abstract: To estimate influence of velocity on kinematic accuracy for a cross-linked Stewart type Parallel Machine Tool, position and orientation errors of the moving tool platform are researched. Based on rigid body dynamics, inertial and friction forces and moments are considered. Firstly, analytical expression of driving force is derived for each link. Secondly, change of length is derived using Hooke’s Law for each link. Then mapping matrix between change of link length and change of platform position and orientation is derived based on both Euler angle and revolving angle around a spatial axis. Finally, analytical expression of position and orientation errors of the moving platform is derived. Figures of distribution of position and orientation errors in workspace under two velocities are obtained respectively. The results show that, in frequently used workspace, all of the three components of position error are less than 3.5μm. All of them increase with z coordinate of platform center. Position error is influenced slightly by velocity. The difference of position error between two velocities is less than 2%.

Abstract: The paper devises a computer vision system based on virtual instruments to measure tape. The dark field illumination is chosen as Lampe-house in this system. Use Image processing technologies of Median filter, Image binarization, Template matching, Edge extraction to extract a reticle of tape. And compare it with standard tape enacted in this system to measure reticle error of the tape. Analyze various factors influencing the detection precision of the system. Tests show that the measurement results of this system are accurate, reliable and practicable.

Abstract: The output characteristics of solar cell that researched as the target is analysed at different temperatures and light intensity .Combining with the equivalent circuit of solar cell, mathematical model is established .The system is simulated through MATLAB/Simulink and the data is compared with the actual one. The experimental results show that the model can well reproduce the output characteristics curve of solar cell at arbitrary condition and the error between the model and the actual output is decreased because of the series resistance. The system can satisfy the requirements of engineering design, in addition, the system can provides theoretical basis for simulation study of solar power generation system.