A maintenance time estimation method based on virtual simulation and improved modular arrangement of predetermined time standards

In the early stage of product design, it is important for maintainability design to evaluate accurate and efficient maintenance time by using the virtual simulation technology. However, the difference between the virtual world and reality results in inaccurate estimation of the maintenance time. Besides, few characteristics of the maintenance tasks and actions are considered, leading to a large estimation error. To solve these problems, this paper presents a maintenance time estimation methodology considering the maintenance action elements (MAEs) and modular arrangement of predetermined time standards (MODAPTS) based on the virtual simulation. To consider fully the features of the maintenance operations, a MAE system is designed and integrated with the MODAPTS to decompose the maintenance task into different basic units for the preliminary time estimation. Meanwhile, to bridge the gap caused by the virtual environment, the association relationship of the MAEs and maintainability is analysed to compensate the extra time spent in the interaction among the humans, machines and environment. Through a case study of an auxiliary power unit starter of a Boeing 737, the proposed method is validated to be capable to describe the difficulty in the practical maintenance process and perform an accurate, efficient and stable maintenance time prediction.