Information Model for Machine-Tool-Performance Tests - Statistical Data Included

This report specifics an information model of machine-tool-performance tests in the EXPRESS [1] language. The information model provides a mechanism for describing the properties and results of machine-tool-performance tests. The objective of the information model is a standardized, computer-interpretable representation that allows for efficient archiving and exchange of performance test data throughout the life cycle of the machine. The report also demonstrates the implementation of the information model using three different implementation methods

This report specifies an information model of machine-tool-performance tests in the EXPRESS modeling language [1]. It is based on the information model described in the Data Specification for Machine Tool Performance Tests, Version 2.3e [2]. The objective of the information model is a standardized, computer-interpretable representation that allows for efficient archiving and exchange of performance test data throughout the life cycle of a machine tool. It serves as a basis for generating database schemas, database calls, and neutral file formats. Performance test data of machine tools is used for machine acceptance, performance tracking, software compensation, and to evaluate the capability of a machine to manufacture a part to specified tolerances.

The information model specifies the test procedure, the test conditions, the equipment, the measurement set-up, and the test results. The model can be used to describe the properties and results of a performance test at a level close to the raw measurement data. The information elements also enable the user to re-create the set-up, equipment settings, and measurement procedure. The model captures key information on the large variety of possible test set-ups and measurement procedures, which is essential for the interpretation of the test results. A subset of the specification can be used to summarize the test, focusing on performance parameters that are estimated from the measurement results.

The information model addresses machine tool properties that are verified by performance tests. It complements machine-tool-specification data that is not tested, e.g., the machine configuration, the workspace, weight and size of the machine, tool holder standard, auxiliary devices, etc. [3].

The information model is intended to serve as the starting point for a future, standardized representation. The model is expected to change and grow based on further review and future implementation experience.

This report is structured as follows: In the remainder of Sec. 1 the problem statement and scope of the information model are defined; modeling language and implementation methods are identified. In Sec. 2 the information model is presented. In Sec. 3 three sample data files are provided. In Sec. 4 software tools that support the implementation of EXPRESS information models are briefed. Section 5 presents the conclusion of this report. An appendix is provided for describing a set of EXPRESS keywords in Sec. 6. The final section lists the references used in this report.

1.2 Problem Statement

Today's manufacturing industry greatly relies on computer technology to support activities throughout a product's life cycle. Efficient and distributed access to the performance data of machine tools is important in manufacturing. The results of performance tests are used for machine acceptance, predictive maintenance, error compensation, and to evaluate the capability of a machine to manufacture parts to specified tolerances. A critical enabler to the efficient interchange and storage of performance data is a unified information model for the results and properties of performance tests.