Papers by Keyword: Measurement

Abstract: Industrial robots are usually not suitable for high-precision applications due to their limited absolute accuracy. This issue can be solved by calibrating the robot using an adequate model of its kinematic chain and physical behaviour. However, this presupposes a deep understanding of the effects that influence the absolute accuracy and repeatability of the robot. This paper outlines a set of experiments to gain this knowledge by analysing the effects that limit the precision and furthermore presents a way for the proper visualisation of the consequent errors. The investigation includes a range of robots with different characteristics to gather valid and preferably universal information for off-the-shelf industrial robots.

Abstract: The following article suggest an analytical model approach for tool temperature prediction in broaching nickel-based alloys. The presented approach is based on an existing model proposed by Komanduri and Hou in 2001, however, includes several modifications in order to better describe the phenomena observed in thermo-graphic measurements acquired during broaching experiments. The novel model approach includes different assumptions regarding the location of heat sources in the cutting zone as well as adiabatic boundary conditions. Moreover, an advancement of the model was made to regard variable contact conditions between tool clearance face and work piece caused by tool wear.

Abstract: Article discusses the diagnosis and control of the operation of artificial muscle with the ability to predict a steady state actuator arm. This can prevent disrepair and provides diagnostics dynamics shoulders. The article contains information about the function and basic properties of the actuator based on pneumatic artificial muscles. The article presents the measurement results of the response of the actuator arm displacement depending on the input pulse. This dependence enables artificial muscles to be better adjusted to the needs of a practical operation.

Abstract: The Genuine Progress Indicator (GPI) is an indicator of measuring sustainability like Green GDP. Apply it to Liaoning Province, the paper evaluates Liaoning’s GPI from 1978 to 2011. GPI, Per Capita GPI and GDP of Liaoning are compared with each other. It is concluded that GDP and Per Capita GDP of Liaoning grow much faster than GPI and Per Capita GPI. Grouped all components of GPI into three categories (economy, environment and Social), it shows that social and environmental development lags behind economic growth in Liaoning.

Abstract: This paper presents a noncontact technique for displacement measurement based on the variation of the pixels positions of a target object in the images captured by CCD or CMOS sensor. A video from a moving structure is made and then it is analyzed frame by frame and the variation of the pixels position of the target object in the structure is calculated for each frame and related with the position of the object in the image. The proposed approach is evaluated to measuring vibrations of a reduced scale model of two-floor building lab structure, which focuses on the advantage of using a unique camera for measurements of structural vibrations. The results obtained are compared to reference model and have shown good agreement.

Abstract: This paper deals with the experimental measurements and computer analysis of the development of heat of hydratation and shrinkage in a large-scale model of a reinforced concrete slab. A large-scale model was built in situ to experimentally verify the design of the reinforcement, with the aim of preventing the formation of cracks in slab. The model represents a four times four meters cut of a slab structure of a thickness of 1.6 m. Bars in the horizontal direction of the slab were extended behind the concrete body and welded to a steel frame, which simulated the anchorage of horizontal reinforcement of a continuous slab. Before casting, the reinforcement bars were fitted with vibrating wire strain gauges and with resistance gauges for monitoring the strain, as well as with temperature sensors for determining the temperature field caused by heat of hydration. According to the needs of the experiment, the structure was modelled in GiD 11.0 software and calculated in the AtenaWin program. The experimental results and the results obtained by a numerical analysis were compared.

Abstract: This paper deals with the experimental measurements and computer analysis of the development of heat of hydration and shrinkage in a large-scale model of a reinforced concrete wall with a base slab. A large-scale model was built in situ to experimentally verify the design of the reinforcement, with the aim of preventing the formation of cracks in a long massive wall located on a base slab. The model represents a four meter cut of a long wall structure (thickness of 1.6 m) together with its base slab (thickness of 1 m). Bars in the longitudinal direction of the wall and of the base slab were extended behind the concrete body and welded to a steel frame, which simulated an anchorage of longitudinal reinforcement of a continuous wall with a base slab. Before casting, the reinforcement bars were equipped with vibrating wire strain gauges and resistance gauges for monitoring the strain, as well as with temperature sensors for determining the temperature field caused by heat of hydration. According to the needs of the experiment, the structure was modelled in GiD 11.0 software and calculated in the AtenaWin program. The results of the experiment and the numerical analysis were mutually compared.

Abstract: A coordinate measuring machine (CMM) is a measuring system with the means to move probing system and capability to determine spatial coordinates on working surface. CMM is used in many industry fields from few micrometers of work pieces to a 5-meter truck. The verification method of CMM is done following international standard. The artifacts for calibrated reference length are the end standards, such as gauge block and step gauge, or laser interferometer for large size CMM. The current laser interferometer is operated by continuous laser and interference fringe counting. One constraint of continuous laser is an incremental measurement. The measurement path cannot be interrupted during the measurement period. We developed a new absolute interferometer system from a short-pulse mode-locked fiber laser. A Fabry–Pérot etalon (FPE) is used to select high-frequency parts of repetition-frequency modes of the mode-locked comb laser at the wavelength of 1.55 μm. The 5-GHz repetition-modified laser beam, which is realized by a new fiber-type FPE, is transmitted to a fiber-type Michelson interferometer. The interference fringes exhibit a temporal coherence interference and can be used for measuring spatial positioning. The temporal coherence between different pairs of modified pulse trains is referred to as absolute length standards. The performance of CMM was determined directly from different positions of two interference fringe patterns.

Abstract: This paper describes possibilities in the use of recycled rubber granules and textile materials combined with vermiculite panel. The aim of the research is the application of materials that will be absorbing or reflecting sound energy. This objective is based on fundamental physical principles of materials research and acoustics. Method of measurement of sound absorption coefficient is based on the principle of standing wave in the impedance tube. With a sound level meter is measured maximum and minimum sound pressure level of standing wave. From the maximum and minimum sound pressure level of standing wave is calculated sound absorption coefficient α_n, which can take values from 0 to 1. Determination of the sound absorption coefficient has been set in 1/3 octave band and in the frequency range from 50 Hz to 2000 Hz. In conclusion are proposed possibilities of application of these materials in terms of their mechanical and physical parameters.

Abstract: In this study, the theory of factor analysis is used to establish a model for measuring and assessing corporate governance and identify major factors affecting corporate governance. The findings of this study can provide theoretical basis for comprehensive evaluation of corporate governance.