Research of Calibration Method for Industrial Robot Based on Error Model of Position

Based on the current situation of high precision and comparatively low APA (absolute positioning accuracy) in industrial robots, a calibration method to enhance the APA of industrial robots is proposed. In view of the "hidden" characteristics of the RBCS (robot base coordinate system) and the FCS (flange coordinate system) in the measurement process, a comparatively general measurement and calibration method of the RBCS and the FCS is proposed, and the source of the robot terminal position error is classified into three aspects: positioning error of industrial RBCS, kinematics parameter error of manipulator, and positioning error of industrial robot end FCS. The robot position error model is established, and the relation equation of the robot end position error and the industrial robot model parameter error is deduced. By solving the equation, the parameter error identification and the supplementary results are obtained, and the method of compensating the error by using the robot joint angle is realized. The Leica laser tracker is used to verify the calibration method on ABB IRB120 industrial robot. The experimental results show that the calibration method can effectively enhance the APA of the robot.

GRID-SITES: Gridded Solar Iterative Temperature Emission Solver for Fast DEM Inversion

The increasing size of solar datasets demands highly efficient and robust analysis methods. This paper presents an approach that can increase the computational efficiency of differential emission measure (DEM) inversions by an order of magnitude or higher, with the efficiency factor increasing with the size of the input dataset. The method, named the Gridded Solar Iterative Temperature Emission Solver (Grid-SITES) is based on grouping pixels according to the similarity of their intensities in multiple channels, and solving for one DEM per group. This is shown to be a valid approach, given a sufficiently high number of grid bins for each channel. The increase in uncertainty arising from the quantisation of the input data is small compared to the general measurement and calibration uncertainties. In this paper, we use the Solar Iterative Temperature Emission Solver (SITES) as the core method for the DEM inversion, although Grid-SITES provides a general framework which may be used with any DEM inversion method, or indeed any large multi-dimensional data inversion problem. The method is particularly efficient for processing larger images, offering a factor of 30 increase in speed for a 10 megapixel image. For a time series of observations, the gridded results can be passed sequentially to each new image, with new populated bins added as required. This process leads to increasing efficiency with each new image, with potential for a ${\approx\,}100$≈100 increase in efficiency dependent on the size of the images.

Historical Traces of a General Measurement Theory in Psychology

A review of the historical measurement theory literature in psychology reveals a recurring focus on a physical rather than a psychological model of the measurement process, whereas the active measurement research literature points to an emphasis on elements of a psychological measurement process. On the basis of the relevant portions of these anomalous findings the authors outline parts of a general measurement structure for psychology that begins with an essential theoretical base. The review first explores a century-old statement that developed a promising starting point within test development. This is followed by a diversionary statement based on physical measurement that mandated discussions of measurement in psychology to a physical model. The statement appeared to be countered by the theory of scale types ( Stevens, 1946 ), which provided a promising element of the psychological measurement process. The legacy of the theory of scales, however, resulted in confusion and inconsistency about the specifics of psychological measurement. After reviewing some of the contributions in the research literature, a conciliation of the positive theory efforts of the past and the protocols for a measurement process are presented that is based upon the standard system of measurement ( Aftanas, 1988 , 2006 ) as the basic theoretically necessary element of measurement. The theoretical framework based on the standard system promises not only to integrate the components of measurement, and categories of psychological measurement that have been referenced in the past, but also to provide an easily assimilated protocol that can serve as a basis for future research and pedagogical exposition.

Four Parameters for Measuring Democratic Deliberation: Theoretical and Methodological Challenges and How to Respond

Although measuring democratic deliberation is necessary for a valid measurement of the performance of democracies, it poses serious theoretical and methodological challenges. The most serious problem in the context of research on democratic performance is the need for a theoretical and methodological approach for “upscaling” the measurement of deliberation from the micro and meso level to the macro level. The systemic approach offers a useful framework for this purpose. Building on this framework, this article offers a modular approach consisting of four parameters for conceptualization, measurement, and aggregation which can be adjusted to make the measurement of democratic deliberation compatible with the various general measurement approaches adopted by different scholars.