Human–Machine Systems Reliability: A Series–Parallel Approach for Evaluation and Improvement in the Field of Machine Tools

Abstract

Machine workshops generate high scrap rates, causing non-compliance with timely delivery and high production costs. Due to their natural characteristics of a low volume, high-mix production batches, and serial and parallel configurations, generally the causes of their failure are not well documented. Thus, to reduce the scrap rate, and evaluate and improve their reliability, their system characteristics must be considered. Based on them, our proposed methodology allows us to evaluate the system, subsystem, and component–subsystem relationship by using either the Weibull and/or the exponential distribution. The strategy to improve the system performance includes reliability tools, expert interviews, cluster analysis, and root-cause analysis. In the application case, the failure sources were found to be mechanical and human errors. The component maintenance/setup, institutional conditions/attitude, and subsystem process/operation were the machine factors that presented the lowest reliability indices. The improved activities were monitored based on the Weibull β and η parameters that affect the system reliability. Finally, by using a life–effort analysis, and the method of comparative analysis of two sequential periods, we identified the causes that generated a change in the Weibull parameters. The contribution of this methodology lies in the grouping of the tools in the proposed application context.

Reliability of Mechatronic Systems and Machine Elements: Testing and Validation

“…In this context, current challenges are related to research on new reliability approaches, but also on machine elements to be used in intelligent mechatronic systems [3,4]. Especially in human-machine systems, interactions with humans and the environment are highly sophisticated [16,17].…”

Reliability of main fan coal mining plants

“…Mine-pit main ventilation fans, and especially those in methane pits and pits where explosive gas and explosive coal dust may occur, are precisely monitored according to regulations, standards, norms, and ordinances [12].…”

“…Using the mathematical functions, forms (1), ( 2), (5), and (12), of the given model for determining the reliability of the fan plant and its indicators and the EXCEL programme, based on the obtained data, a basic reliability analysis was obtained.…”

Monitoreo de la confiabilidad del sistema hombre-máquina del área de mecanizado mediante la distribución de Weibull

“…This is to incorporate the monitoring information into the Series-Parallel statistical model, for the control and improvement of the reliability of the man-machine system, reducing the number of failures that generate scrap and can thus fulfill orders promptly. The monitoring of the changes in the Weibull parameters was done by monitoring the magnitudes of the stresses applied when manufacturing the parts [10].…”