William G. Rippey

Unique sensor fusion system for coordinate-measuring machine tasks

This paper describes a real-time hierarchical system that fuses data from vision and touch sensors to improve the performance of a coordinate measuring machine (CMM) used for dimensional inspection tasks. The system consists of sensory processing, world modeling, and task decomposition modules. It uses the strengths of each sensor -- the precision of the CMM scales and the analog touch probe and the global information provided by the low resolution camera -- to improve the speed and flexibility of the inspection task. In the experiment described, the vision module performs all computations in image coordinate space. The parts boundaries are extracted during an initialization process and then the probes position is continuously updated as it scans and measures the part surface. The system fuses the estimated probe velocity and distance to the part boundary in image coordinates with the estimated velocity and probe position provided by the CMM controller. The fused information provides feedback to the monitor controller as it guides the touch probe to scan the part. We also discuss integrating information from the vision system and the probe to autonomously collect data for 2-D to 3-D calibration, and work to register computer aided design (CAD) models with images of parts in the workplace.

Evaluation of component-based reconfigurable machine controllers

The lack of interoperability and integration standards is severely hindering manufacturing productivity. To address this problem, a general motion control (GMC) testbed has been developed at National Institute of Standards and Technology (NIST) with one of its goals to validate the open modular architecture controller (OMAC) interface specification for reconfigurable, plug-and-play open-architecture controllers. The GMC validation testbed was built using Microsoft component object model (COM) components. This paper reviews software programming issues and the use of Microsoft COM in the development of machine control components. Strategies and tests of COM programming for a controller are discussed.

Quality Information Framework – Integrating Metrology Processes

Abstract As defined by major dimensional metrology system users and suppliers, the Quality Information Framework (QIF) is an integrated and holistic set of information models which, if widely adopted, can enable the effective exchange of metrology data throughout the entire manufacturing quality measurement process – from design to planning to execution to analysis. This paper introduces the philosophy and rationale behind QIF, as well as some of its detailed content. Past standards efforts in manufacturing quality systems have had a variety of shortcomings, which QIF plans to overcome. The QIF data models have been encoded in Extensible Modeling Language (XML) schemas. Schemas developed during the first year of the QIF project include the QIF schema library and the Quality Measurement Results (QMResults) schema. QIF models quality characteristics and measurement features as defined in the ASME Y14.5 specification, and is able to cover use cases including reverse engineering, batch quality measurement, and discrete quality measurement. Correct semantic associations between measurement feature and quality characteristics, and between nominal values and actual values, are guaranteed by implementing strong typing using identifiers. The next step of the QIF project is to conduct a set of pilot tests to validate the information models.

Network communications for weld cell integration – status of standards development

Network technology is being used more and more to replace direct‐wired links to integrate equipment making up automated and semi‐automated welding systems. Two formal welding standards efforts, one by the American Welding Society A9 Committee and the other by the Open DeviceNet Vendor Association (ODVA) are described. This paper should be useful to users and integrators of weld cells as part of their evaluation of the different network technologies available for implementation of welding systems.

Toward Better Integration of Vehicle Assembly Production Systems

In today’s manufacturing world, system integration often necessitates composing systems of technology that are not designed to interoperate with each other. This inherent incompatibility results in redundant, non–value added work that is required for information to be properly transferred and processed in order for the total system to function properly. As a result, current approaches to systems integration tend to be complicated, costly, time–consuming, and error–prone. In the automotive industry, this integration predicament is found most dramatically in vehicle assembly systems, which are built from a collection of different, incompatible, and multi–vendor “silo” subsystems. This paper investigates the problems associated with integration of vehicle assembly systems and proposes a standard information and communication model to address the integration problems due to incompatible data models. Benefits to the standard information and communication model, including better integration, improvements to the efficiency of the existing vehicle assembly operations, and additional capabilities to increase productivity, is discussed. NOMENCLATURE API Application Programming Interface CNC Computer Numerical Control COM Microsoft Component Object Model DA Data Access DCOM Distributed Component Object Model COTS Commercial–Off–The–Shelf ERP Enterprise Resource Planning FTP File Transport Protocol HMI Human Machine Interface HTTP Hypertext Transfer Protocol IO Input/Output IP Internet Protocol IT Information Technology MAP Manufacturing Automation Protocol MMS Manufacturing Message Specification MES Manufacturing Execution Systems OLE Object Linking and Embedding OPC OLE for Process Control PC Personal Computer PLC Programmable Logic Controller REST REpresentational State Transfer SCADA Supervisory Control and Data Acquisition SDK Software Development Kit SOA Service Oriented Architecture SOAP Simple Object Access Protocol W3C World Wide Web Consortium WS Web Services XML eXtensible Markup Language XSD XML Schema Definition BACKGROUND Assembly efficiency and capability is a competitive discriminator in every product manufacturing sector [1]. In theory, advances in robotics, sensors, controls, effectors, and material handling could support the easy deployment and routine production of customized products in a single assembly production line. However, the problems associated with integration, configuration, and programming of assembly systems has hampered the cost–effective use and production efficiency of assembly systems. The problems with assembly systems can be attributed to incompatibilities between assembly subsystems that are not designed to interoperate and communicate with each other. This inherent incompatibility results in redundant, non–value added work that is required for information to be properly transferred and processed in order for the total system to function properly. As a result, current