I++ DME (Dimensional Measurement Equipment)

Summary

The I++ (Inspection plus-plus) group is a loose consortium of European automobile manufacturers: Daimler, Audi, BMW, Opel, Volkswagen, Porsche, and Volvo. I++ DME is one of two current efforts pursued by the I++ group. I++ DME has demonstrable support from U.S. users and vendors of coordinate measuring machines (CMM) and CMM measurement plan execution software.

The scope of this industry-led effort is on the exchange of dimensional measuring equipment commands and results between measurement execution software and a CMM.

NIST's role is to 1) contribute to the writing of I++ DME, 2) generate conformance tests, 3) design and conduct public interoperability tests, and 4) act as standards consultants and leaders in industry standards organizations through summit meetings and other initiatives.

Description

Industry Impact

• Adoption of  I++ DME by a majority of vendors worldwide with compliant apps has been largely achieved due to

• Strong end user and CMM vendor support through groups such as I++ group, NIST, Dimensional Metrology Standards Consortium, International Association of CMM Manufacturers, and the Automotive Industry Action Group
• NIST I++ DME compliance test suite, allowing quick and compliant implementation development
• Five successful, non-trivial public interoperability tests in Europe and the U.S. initiated and lead by NIST, with willing participation for CMM software and hardware vendors worldwide  
• Implementers meetings and public wiki site for implementer/spec-writer interaction
• Detailed analysis of the I++ DME specification by NIST and others early in the life of I++ DME

Status

• I++ DME is NOT a standard, but rather a tightly controlled specification by a small group of CMM vendors and CMM end users
• Legal problems and concerns expressed at the NIST-organized Metrology Interoperability Summit Meeting 2006, were later addressed satisfactorily by the I++ Group
• I++ DME is for fixed CMMs only, and it remains to extend I++ DME to a variety of other types of CMMs, including CMMs with non-contact optical sensors, laser trackers, and articulated arm CMMs
• The I++ group has a vision for the entire standards infrastructure (includes I++ DMS)
• Commercial-Off-The-Shelf offerings of I++DME-compliant products are rare, even though the capability exists in alpha and beta software versions

To-Do List

• Harmonize America, Europe, Asia visions about the precise information content on the DME interface
• Encourage I++ DME standardization
• Encourage Commercial-Off-The-Shelf offerings of I++DME-compliant products
• Update NIST compliance test suite
• Extend I++ DME to portable metrology devices