TRL (Technology Readiness Level)

Technology Readiness Level 

TRLTechnology Readiness Level is a measure on a scale of 1 to 9 of how developed a piece of technology is, starting from an initial idea or concept, through the various prototyping stages, to a commercially available product that conforms to all of the necessary regulations. The definition of each level is defined in the table below.

 TRL Definition
1 Sensitivity to defects, wall thickness, etc, demonstrated in laboratory conditions.
2 The physics underpinning the technology use is well established.
3 Technology proof-of-concept demonstrated.
4 Technology demonstrated in laboratory conditions.
5 Technology performance (capabilities and limitations) changes with real conditions determined.
6 Prototype technology tested in an operational environment.
7 Prototype technology validated to be used in operational environment conditions.
8 Technology is commercially available and has been approved by relevant regulatory bodies and PCN Level 3 involvement.
9 Technology is commercially available and used in at least one industry setting.

The product or technology that is being evaluated could be hardware, software or a system combining both:
  • Hardware: for example, a robotic probe manipulator for the provision of automated inspection data collection.
  • Software: for example, a suite of image processing techniques to aid inspection data interpretation.
  • System: for example, a collaborative robot (hardware) that uses sophisticated path planning tools (software) to inspect complex materials.

The Research Centre in Nondestructive Evaluation (RCNDE) uses this technology readiness scale to evaluate the progress made by non-destructive testing (NDT) research projects, as do various other UK and international industries and research organisations.

For more information on TRL see:

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