Intelligent Open Architecture Control of Manufacturing Systems

Interface Standards to Ease Integration and Enhance Functionality

Need

This program addresses control and interoperability at the unit process level

Over the past two decades, information technology has dramatically increased the intelligence of the upper levels of manufacturing systems. In the next twenty years, this intelligence will reach down to the factory floor as individual machines become much smarter, able to communicate more broadly, to integrate more easily, to predict results and avoid or diagnose mistakes, to use extensive in-process gaging, and to use scientific models to optimize productivity.

These trends-echoed in the IMTR Roadmap have great potential to decrease time and cost to market, improve quality, and increase productivity. However, they require a seamless flow of information and total integration throughout the enterprise, and today, in the words of one workshop attendee, "all the links are broken."

Open architecture control-a common architecture of system components and interfaces-is the key to connecting the links and to realizing the benefits of increased intelligence in manufacturing processes.

Industry is looking to NIST to play a leadership role in working with them to turn the vision of open architecture control into reality, and in much less time than the normative standards process typically takes.

"We don't have time to wait. NIST must play a leadership role in resolving these standards problems."-Daimler Chrysler.

In this program we are responding to this challenge by establishing testbeds and using them to help industry validate the architecture and interface standards needed to get open architecture controls for machine tools, robots, and automated metrology equipment into the marketplace. We will also develop conformance tests that companies can use to make sure that the systems they buy work together.

How much is the current lack of interoperability costing U.S. industry? Taking industrial robots as an example, the total installed system cost is typically 3 to 5 times the cost of the robot itself (1999 Robotics Industry Forum). In a $1 B U.S. robot market (1999), this equates to $2 B to $4 B of added costs. If only 25 % of these were attributable to software integration, and if they could be reduced by 50 % through the development and use of standardized open architecture controllers, the potential savings would be $250 M to $500 M per year. A look at cell integration costs in the aerospace industry paints a picture of comparable potential savings: $10 M of capital equipment takes 100 person-years to integrate (Boeing data).

Ultimately, success for this program means a dramatic reduction of these software integration costs, and market availability of commercial open architecture controllers and software modules that improve manufacturing equipment productivity and product quality.

The time is ripe for open architecture control standardization:

Goals

By 2005, Develop and validate the following key interface standards, and conformance tests for those standards, to achieve interoperability of control systems for machines on the factory floor with design and planning systems, with factory data networks and with each other:

Approach

Our approach is to realize interoperability by facilitating and participating in industry efforts to standardize open architecture control. Interoperability requires three steps:

We are involved in each of these steps. We hold workshops-in collaboration with industry and government agencies-to identify the most pressing interoperability problems. We facilitate and participate in industry efforts to develop suitable architectures as a basis for interface specifications. We establish testbeds with real manufacturing equipment to implement and test candidate specifications. In cases where conformance tests are needed to ensure interoperability, we work with industry members to develop them.

Currently we are currently working closely with groups representing three market sectors. These include:

We are also collaborating with the Integrated Manufacturing Technology Initiative to identify and address control-related problems that need to be solved to achieve the long-sought goal of First Part Correct.

Through this program, we hope to accelerate the implementation and commercial availability of controllers with advanced capabilities, and to reduce controller life cycle costs due to easier integration of controller components and increased competition among controller component vendors. This benefits U.S. controller vendors and users differentially by helping them achieve a competitive advantage in implementing and applying advanced capabilities at lower costs.

Progress

Robotic Industries Association R15.04 Communication Committee Reconvened
The Robotic Industries Association (RIA) R15.04 Communication and Information Committee was reconvened as a result of interest in standards for network integration of robot controllers arising from the NIST/RIA workshop series on open architecture control. The committee is comprised of robot vendors (Fanuc Robotics North America, Kuka Development Laboratories), robot users (General Motors, Ford), and third parties (B2D Solutions, Radix Controls, Pilz Automation, NIST, RIA). At a meeting held April 19 in Detroit, MI, the group discussed publishing a technical report derived from the communication requirements in GM's General Requirements Specification for robot controllers. These include Ethernet, TCP/IP, and FTP, with additional classification of robot controller data files intended to enable uniform file upload, download, and compare (UDC) across vendors. The draft report has been circulated and was presented at the RIA Robots and Vision conference in Chicago in June 2001.

Interoperability Testing Tools for Metrology Equipment Successfully Demonstrated
Shortening time to market is a strategic imperative for U.S. manufacturers in an increasingly competitive global marketplace. Achieving a seamless flow of data from CAD part models to equipment on the factory floor is a key requirement to shorten product cycles. In the area of metrology equipment, one of the key interfaces that NIST has identified to focus on is the interface between the metrology hardware, the coordinate measuring machine for example, and the control system for that hardware. NIST is working with the Metrology Automation Association to develop a standard for this interface, which is called the Common Machine Interface (CMI). Industry is setting the specifications and NIST is providing testing tools. At the SIMA Annual Review in July, NIST researchers teamed with one of the leading manufacturers of metrology equipment, LK Metrology, to demonstrate the CMI test suite. John Horst, Hui-min Huang, and Harry Scott of NIST and Dave Smith of LK Metrology successfully presented and demonstrated the CMI test suite effort. Developers of the demonstrated system also included Keith Stouffer, Joe Falco and Tom Kramer. Demonstrated were the NIST-developed common sender and receiver utilities, a common test artifact, and an implementation of CMI on a Coordinate Measurement Machine by LK. The demonstration of the test suite included the transmission of a CMI compliant test file from the NIST AMSANT lab to the facility at LK in the U.K., execution of the file on the CMM at LK to inspect features on the test part, monitoring and collection of status information, and review of test log files with preliminary analysis tools. The demonstration included transmission of live video and audio over the internet from the LK location in England to the AMSANT Lab at NIST. Other major participants in defining the CMI include Brown & Sharpe and Zeiss.

NIST Encourages Harmonization of Conflicting Standards for Dimensional Inspection
In developing standards for closely related activities, it is inevitable that separate standards groups will rework the same turf. To make interoperable standards, when turf overlaps the groups involved must harmonize their efforts. At a meeting hosted by Brown & Sharpe in Wixom, Michigan, November 14 - 16, representatives of three MEL divisions (ISD, MSID, and PED) participated in an effort to harmonize a developing ISO standard (ISO 10303, AP 219, Dimensional Inspection) with an existing CAM-I/ANSI standard undergoing revision (Dimensional Measuring Interface Standard Version 4.0). Other attendees included vendors, users, and federal laboratories representing both standards committees. Good progress was made in achieving mutual understanding. The goal of achieving semantic equivalence in areas common to the two standards was adopted, and a model was developed providing semantic equivalence of inspection features. NIST is playing a proactive role, having initially proposed this harmonization effort and having committed to providing an EXPRESS schema for DMIS 4.0 and a DMIS to STEP converter to enable interoperability.

Workshops on Open Architecture Control for Robotics
NIST and RIA co-sponsored a series of workshops on open architecture control for robotics. The series has included these meetings:

November 2000 - NIST Encourages Harmonization of Conflicting Standards for Dimensional Inspection
Three MEL divisions (ISD, MSID, and PED) participated in an effort to harmonize a developing ISO standard (ISO 10303, AP 219, Dimensional Inspection) with an existing CAM-I/ANSI standard undergoing revision (Dimensional Measuring Interface Standard Version 4.0). The meeting took place at the Brown and Sharpe facility in Wixom, MI. The goal of achieving semantic equivalence in areas common to the two standards was adopted, and a model was developed providing semantic equivalence of inspection features.

November 2000 - Demonstration of STEP/NC by NIST ATP awardee STEP Tools, Inc.
STEP Tools, Inc. demonstrated the integrated design, process planning, and execution of a standard test part using STEP data and the proposed ISO 14649 standard for integration of STEP with machining. STEP Tools is conducting this work under NIST ATP funding, and NIST is a member of the industrial review board that oversaw planning for the demonstration.

November 2000 - Presentations on open architecture control at the SPIE annual conference on Sensors and Controls for Intelligent Manufacturing
John Michaloski, Fred Proctor, and Keith Stouffer presented NIST's work on open architecture control, including software application programming interfaces, open source availability of control software, and real-time simulation.

November 2000 - Presentation on open architecture control at the RIA Annual Forum
John Evans presented NISTŐs work in open architecture control for the robotics industry, including related work for machine tools and automated metrology equipment.

November 2000 - General Motion Control Requirements for the Packaging Industry
John Michaloski and guest researcher Sri Kolla met with representatives from large packaging equipment users, including Hershey's, M&M Mars, and Procter & Gamble, at the OMAC Packaging meeting during Pack Expo in Chicago. Also participating were principal packaging equipment suppliers such as SIG Pack, R.A. Jones, and Klockner. Other informal meetings were held with ARC, RA Jones, and SIG Pack. A meeting with Dennis Daniels, Bill Krah, and Sal Spada of ARC was held about further promoting open architecture and how ARC could help NIST with its General Motion Control Testbed.

September 2000 - Parallel Kinematics International Conference
Al Wavering participated in the Year 2000 Parallel Kinematic Machines International Conference. Majority attendance was by oversees representatives. U.S. participation included Ingersoll, General Motors, Caterpillar, TRW Automotive, Hardinge, Bosma Machine and Tool, Pathfinders, and Federal Mogul. Presentations included updates on new machines being built, and descriptions of work in calibration, modeling, and optimization of PKM machines.

September 2000 - OMAC API Presentation to OMAC Human-Machine Interface Working Group
John Michaloski participated in the OMAC Human-Machine Interface Working Group meeting at the International Manufacturing Technology Show (IMTS) in Chicago, IL on September 8. At this meeting, the OMAC Application Programming Interface (API) was discussed, and its relationship to the communication link between the graphical operator display and control panel devices and machine tool controllers.

July 2000 - Ad Hoc planning meeting of members of ISO TC184/SC1/WG7
The committee members responsible for the proposed ISO 14649 standard for STEP integration with machine tool control met at the University of Aachen to discuss coordinating international efforts at validating the standard. Coordination of STEP Tools, Inc.'s work for the NIST ATP with the international IMS project was discussed. U.S. participation in the IMS project through STEP Tools as the principal was proposed, and agreed to during follow-up discussions.

Projects Associated with this Program

General Motion Control Testbed

National Metrology Testbed

OMAC Application Programming Interfaces

Robot Integration Testbed

STEP/NC

Welding Testbed

Contact

Mr. Frederick M. Proctor
NIST
Intelligent Systems Division
100 Bureau Drive Stop 8230
Gaithersburg, MD 20899-8230
Phone: 301-975-3452
Fax: 301-990-9688
E-mail:frederick.proctor@nist.gov

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Date created: 1/25/2001
Last updated: June 13, 2001