National Physical Laboratory

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    NPL maintains a wide portfolio of internationally visible research programmes that advances measurement science, underpins the SI system and supports various cross-disciplinary technologies.

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    • Measurement in 2020

      Kamal Hossain, Director of Research and International, outlines in QMT magazine, how NPL is rising to meet the measurement challenges of the next two decades.
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    • Order from disorder

      Collaborative research into a protein associated with Parkinson’s disease explores a novel way of organising proteins at the nanoscale.
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    • Radiotherapy doses to be more accurate

      Collaborative research on the distribution of charged particles during treatment will contribute to safer radiotherapy for cancer patients.
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    • The tick-tock of the optical clock

      A new frequency measurement in an ytterbium ion could form the basis for the next generation of optical atomic clocks.
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      Thanks to NPL Training, the measurement associates are now thinking out of the box. We are already seeing a faster turnaround of measurement activities with higher accuracy and increased confidence. NPL is known for its technical expertise in this area, and can provide the highest level validated training. It's added to our professionalism and improved communication with our suppliers.

      Mark Imms
      Metrology Manager
      Bentley Motors

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      NPL has provided us with very valuable services, which have helped ensure that our satellites offer the accuracy needed provide our customers with technology they can trust, and remain ahead of our competitors.

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      Surrey Satellite Technology Ltd

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      BP Exploration has continued to benefit from NPL's world class corrosion testing and modelling capabilities in 2009, and we intend to cooperate even more closely in 2010 and beyond.

      Steve Groves
      Programmes Manager
      Inherently Reliable Facilities Flagship BP
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    We strive to actively promote public awareness and appreciation of science and technology, particularly the importance of measurement and the role of NPL. Here you can find out more about the interesting things we do, science outreach activities you can get involved in or take a look at some of our educational resources.

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    Measurement Network

    The Measurement Network is the UK’s national network set up to support businesses to solve measurement challenges, increase the spread and adoption of measurement knowledge and address strategic measurement issues.

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I need to calibrate my CMM, or do I mean verify it or error map it or qualify it? I am confused. (FAQ - Length)

A manufacturer will calibrate a CMM and produce an error map that corrects for the various geometric errors in the machine.

When delivered an acceptance test will be carried out on the machine to verify that it meets its specification. This verification should be repeated periodically to check that the machine is still within specification (reverification). In addition interim checks should be carried out.

When using the machine the probing system will need to be qualified by measuring a material standard of known dimension (usually a reference sphere).

For more information see ISO 10360.

International Standard ISO 10360 covers CMM verification. This standard has five parts:

  • ISO 10360-1:2000 Geometrical Product Specifications (GPS) - Acceptance and reverification tests for coordinate measuring machines (CMM)-Part 1: Vocabulary
  • ISO 10360-2:1994 Coordinate Metrology-Part 2: Performance assessment of coordinate measuring machines
  • ISO 10360-3:2000 Geometrical Product Specifications (GPS) - Acceptance and reverification tests for coordinate measuring machines (CMM)-Part 3: CMMs with the axis of a rotary table as the fourth axis
  • ISO 10360-4:2000 Geometrical Product Specifications (GPS) - Acceptance and reverification tests for coordinate measuring machines (CMM)-Part 4: CMMs used is scanning measuring mode
  • ISO 10360-5:2000 Geometrical Product Specifications (GPS) - Acceptance and reverification tests for coordinate measuring machines (CMM)-Part 5: CMMs using multiple-stylus probing systems
Last Updated: 1 Dec 2010
Created: 1 Dec 2010