Allison Barnard Feeney

A Portrait of an ISO STEP Tolerancing Standard as an Enabler of Smart Manufacturing Systems

The International Organization for Standardization (ISO) has just completed a major effort on a new standard ISO 10303-242 titled “Managed Model Based 3D Engineering.” It belongs to a family of standards called STEP (STandard for the Exchange of Product model data). ISO 10303-242 is also called the STEP Application Protocol 242 (STEP AP 242, for short). The intent of STEP AP 242 is to support a manufacturing enterprise with a range of standardized information models that flow through a long and wide “digital thread” that makes the manufacturing systems in the enterprise smart. One such standardized information model is that of tolerances specified on a product’s geometry so that the product can be manufactured according to the specifications. This paper describes the attributes of smart manufacturing systems, the capabilities of STEP AP 242 in handling tolerance information associated with product geometry, and how these capabilities enable the manufacturing systems to be smart.

The STEP Modular Architecture

The first Technical Note in this series [1] introduced the international standard ISO 10303, informally known as STEP (STandard for the Exchange of Product model data). Subsequent Technical Notes discussed various issues faced by users of STEP and how the ISO TC184/SC4 committee is addressing these issues. This paper presents the current move to modularize the STEP application protocol architecture. This paper describes the initial STEP architecture, requirements for improvements to the architecture, features of the new modular architecture, status and issues.

Technical note: Recent advances in sharing standardized STEP composite structure design and manufacturing information

Composite structures have been developed and used in the aerospace, automobile, sports, and marine industries since the early 1940s. Compared to conventional metallic structures, newer high-performance composite structures provide benefits such as decreased weight and reduced energy consumption. An international standards subcommittee on industrial automation systems and integration has developed and implemented a standard, ISO 10303-209, for sharing the manufacturing information for these complex composite structures. This standard, part of the family of standards commonly known as the Standard for Exchange of Product model data (STEP), is considered essential for improving the design, analysis, and manufacturing productivity of composite structures. The ISO 10303-209 standard also enables the long-term data retention necessary to support the composite structures throughout the lifetime of the products that use them. This paper describes recent advances that led to the development of ISO 10303-209 data models for composite structural shape and composition. The paper also reports the status of ongoing implementation and testing efforts. Varied usage scenarios have motivated several areas for future improvement, such as full three-dimensional representation and the efficient cost-effective visualization of composite structural parts. Issues and their proposed solutions, along with their anticipated impacts on the design, analysis, manufacturing, and long-term support of composite structures are also discussed.

Toward a Lifecycle Information Framework and Technology in Manufacturing

Industry has been chasing the dream of integrating and linking data across the product lifecycle and enterprises for decades. However, industry has been challenged by the fact that the context in which data is used varies based on the function / role in the product lifecycle that is interacting with the data. Holistically, the data across the product lifecycle must be considered an unstructured data-set because multiple data repositories and domain-specific schema exist in each phase of the lifecycle. This paper explores a concept called the Lifecycle Information Framework and Technology (LIFT). LIFT is a conceptual framework for lifecycle information management and the integration of emerging and existing technologies, which together form the basis of a research agenda for dynamic information modeling in support of digital-data curation and reuse in manufacturing. This paper provides a discussion of the existing technologies and activities that the LIFT concept leverages. Also, the paper describes the motivation for applying such work to the domain of manufacturing. Then, the LIFT concept is discussed in detail, while underlying technologies are further examined and a use case is detailed. Lastly, potential impacts are explored.

Testing STEP-NC implementations

STEP (STandard for the Exchange of Product model data, ISO 10303) data for numerical control, or STEP-NC, is intended to provide full product and process data interoperability between computer-aided manufacturing systems and machine tool controllers. Numerous prototype and several commercial implementations of STEP-NC are currently being developed. Testing is an essential step toward ensuring conformance to a specification and achieving interoperability between different implementations. Test methods and valid test cases that address specific operational scenarios are vital to speed the development process. This paper describes proposed test methods and metrics, validation methods for test data, and test case development.

TOWARDS KNOWLEDGE MANAGEMENT FOR SMART MANUFACTURING

The need for capturing knowledge in the digital form in design, process planning, production, and inspection has increasingly become an issue in manufacturing industries as the variety and complexity of product lifecycle applications increase. Both knowledge and data need to be well managed for quality assurance, lifecycle-impact assessment, and design improvement. Some technical barriers exist today that inhibit industry from fully utilizing design, planning, processing, and inspection knowledge. The primary barrier is a lack of a well-accepted mechanism that enables users to integrate data and knowledge. This paper prescribes knowledge management to address a lack of mechanisms for integrating, sharing, and updating domain-specific knowledge in smart manufacturing. Aspects of the knowledge constructs include conceptual design, detailed design, process planning, material property, production, and inspection. The main contribution of this paper is to provide a methodology on what knowledge manufacturing organizations access, update, and archive in the context of smart manufacturing. The case study in this paper provides some example knowledge objects to enable smart manufacturing.

Systems Engineering Foundations of Software Systems Integration

This paper considers systems engineering processes for software systems integration. Systems engineering processes, as intended here, concern how engineering capability should be factored into problem-solving agencies for performance of software systems integration tasks. Systems engineering processes also concern how the results produced by these agencies should be communicated and integrated into a system solution. The environment in which systems integration takes place is assumed to be model-driven. In the proposed solution, problemsolving agencies, working from various viewpoints, employ differing notations and analytical skills. In the course of identifying the systems engineering process, the paper presents a conceptual model of systems engineering, and reviews a classification of impediments to software systems integration.

Promoting Model-Based Definition to Establish a Complete Product Definition

The manufacturing industry is evolving and starting to use 3D models as the central knowledge artifact for product data and product definition, or what is known as Model-based Definition (MBD). The Model-based Enterprise (MBE) uses MBD as a way to transition away from using traditional paper-based drawings and documentation. As MBD grows in popularity, it is imperative to understand what information is needed in the transition from drawings to models so that models represent all the relevant information needed for processes to continue efficiently. Finding this information can help define what data is common amongst different models in different stages of the lifecycle, which could help establish a Common Information Model. The Common Information Model is a source that contains common information from domain specific elements amongst different aspects of the lifecycle. To help establish this Common Information Model, information about how models are used in industry within different workflows needs to be understood. To retrieve this information, a survey mechanism was administered to industry professionals from various sectors. Based on the results of the survey a Common Information Model could not be established. However, the results gave great insight that will help in further investigation of the Common Information Model.

Ambulance Design Survey 2011: A Summary Report.

Current ambulance designs are ergonomically inefficient and often times unsafe for practical treatment response to medical emergencies. Thus, the patient compartment of a moving ambulance is a hazardous working environment. As a consequence, emergency medical services (EMS) workers suffer fatalities and injuries that far exceed those of the average work place in the United States. To reduce injury and mortality rates in ambulances, the Department of Homeland Security Science and Technology Directorate has teamed with the National Institute of Standards and Technology, the National Institute for Occupational Safety and Health, and BMT Designers & Planners in a joint project to produce science-based ambulance patient compartment design standards. This project will develop new crash-safety design standards and improved user-design interface guidance for patient compartments that are safer for EMS personnel and patients, and facilitate improved patient care. The project team has been working with practitioners, EMS workers’ organizations, and manufacturers to solicit needs and requirements to address related issues. This paper presents an analysis of practitioners’ concerns, needs, and requirements for improved designs elicited through the web-based survey of ambulance design, held by the National Institute of Standards and Technology. This paper also introduces the survey, analyzes the survey results, and discusses recommendations for future ambulance patient compartments design.

Gaps Analysis of Integrating Product Design, Manufacturing, and Quality Data in the Supply Chain Using Model-Based Defintion

Advances in information technology triggered a digital revolution that holds promise of reduced costs, improved productivity, and higher quality. To ride this wave of innovation, manufacturing enterprises are changing how product definitions are communicated - from paper to models. To achieve industrys vision of the Model-Based Enterprise (MBE), the MBE strategy must include model-based data interoperability from design to manufacturing and quality in the supply chain. The Model-Based Definition (MBD) is created by the original equipment manufacturer (OEM) using Computer-Aided Design (CAD) tools. This information is then shared with the supplier so that they can manufacture and inspect the physical parts. Today, suppliers predominantly use Computer-Aided Manufacturing (CAM) and Coordinate Measuring Machine (CMM) models for these tasks. Traditionally, the OEM has provided design data to the supplier in the form of two-dimensional (2D) drawings, but may also include a three-dimensional (3D)-shape-geometry model, often in a standards-based format such as ISO 10303-203:2011 (STEP AP203). The supplier then creates the respective CAM and CMM models and machine programs to produce and inspect the parts. In the MBE vision for model-based data exchange, the CAD model must include product-and-manufacturing information (PMI) in addition to the shape geometry. Todays CAD tools can generate models with embedded PMI. And, with the emergence of STEP AP242, a standards-based model with embedded PMI can now be shared downstream. The on-going research detailed in this paper seeks to investigate three concepts. First, that the ability to utilize a STEP AP242 model with embedded PMI for CAD-to-CAM and CAD-to-CMM data exchange is possible and valuable to the overall goal of a more efficient process. Second, the research identifies gaps in tools, standards, and processes that inhibit industrys ability to cost-effectively achieve model-based-data interoperability in the pursuit of the MBE vision. Finally, it also seeks to explore the interaction between CAD and CMM processes and determine if the concept of feedback from CAM and CMM back to CAD is feasible. The main goal of our study is to test the hypothesis that model-based-data interoperability from CAD-to-CAM and CAD-to-CMM is feasible through standards-based integration. This paper presents several barriers to model-based-data interoperability. Overall, the project team demonstrated the exchange of product definition data between CAD, CAM, and CMM systems using standards-based methods. While gaps in standards coverage were identified, the gaps should not stop industrys progress toward MBE. The results of our study provide evidence in support of an open-standards method to model-based-data interoperability, which would provide maximum value and impact to industry.