Enhanced Crack Ruler

Introducing enhanced crack ruler

The ‘enhanced’ crack ruler is an innovative transparent ruler for measuring the width of a crack. This new version of the graduated crack gauge allows you to measure the width in 2 ways:

• either manually using the graduated lines, as with a conventional graduated crack ruler
• or automatically using the Saugnac application and its unique augmented reality image processing process.

Thanks to its innovative image processing and analysis technology, the application calculates the width of the crack at the selected point on the crack. To do this, it uses the graduations of the crack ruler as a reference.

Note: the Saugnac ‘enhanced’ crack ruler is not designed to measure the evolution of a crack over time. To do this, it is necessary to use measuring instruments designed for this purpose, in particular crack monitors for 1-axis monitoring.

Visual reading – Measuring the width of a crack of less than 2 mm

Buying a graduated crack ruler makes it very easy to read the width of the crack. Simply apply your Saugnac crack gauge to the crack and slide it until the graduated line exactly overlaps the thickness of the crack.

The examples above read 0.1 mm, 0.4 mm and 1.5 mm respectively.

Visual reading – Measuring the width of a crack greater than 2 mm

If the crack is wider than 2 mm, use the graduated ruler and position it to measure the width of the crack directly.

In the example opposite, the reading is 3 mm.

Reading the crack ruler in augmented reality with the Saugnac application

To take a reading using the Saugnac application, make sure you have followed the preparatory steps, then proceed to the 4-step measurement.

Accessing the Saugnac application and positioning the graduated crack ruler

The augmented reality reading function on Saugnac crack ruler can be accessed without installation from the https://saugnac.app website by clicking on ‘ Measure using the crack ruler ’ or simply by scanning the QR code on the crack ruler.

The crack ruler must then be positioned so that the part of the crack to be measured is visible in the crack ruler’s reading frame. The QR code and the 4 graduated lines above and below it must be visible, as well as the two lines on the right, for the measurement analysis to work correctly.

1 – Validating the start of the analysis

Once you have positioned the crack ruler, you can validate the start of the analysis by clicking on the button.

2 – Detection of the Saugnac crack ruler

The application scans the image to detect the crack ruler. If detection is difficult:

• change the camera by clicking on the button . The application is designed to work with standard cameras. Sometimes the wide-angle camera on your device is the one used by default, so you will need to change it.
• try moving slightly forwards or backwards

Note that the application associated with enhanced crack ruler only works with recent phones with a good quality camera and a sufficiently powerful processor to carry out the analysis.

3 – Identifying the area of the crack to be measured

Once the fissurometer has been detected, you can point to the area of the crack to be measured on the smartphone.

4 – Calculating and displaying the result

The application performs the calculation and displays the result. The width of the crack is displayed. The zoom button is used to enlarge the image to better see the modelling of the edges and any detection errors. You can click on another area to calculate the width at another point within the measurement frame.