IR Speeds Automotive System Testing

In the automotive testing world, thermal imaging cameras are extremely useful tools. Here is just one example of how they have used thermal imaging cameras to save time and money within the automotive field.

The design of windshield defrost demist ducting is complex and hampered by the dimensional constraints due to other essential vehicle parts. It can be difficult to provide an adequate and evenly distributed airflow to the inner face of the glass.

To validate a design, a typical defrost development test is as follows:-

Following design guidelines for the intended market a vehicle needs to be chilled to -20°C or so and soaked (to achieve uniform temperature) for up to 8 hours to ensure a known start point. The windshield has a known amount of water sprayed on and is left to cure for several minutes to establish uniform crystal consistency. The vehicle engine is started and allowed to idle with the appropriate heater/windshield defrost settings. 

Here is where a thermal imaging camera is needed. As the engine heats up and warm air flows through the defrost ducting, a thermal imaging photo shows the thaw pattern developing on the screen.
At set intervals, a recording is made of this thaw pattern.  In addition, a certain area of glass must be clear of ice within a predefined time, as defined by the Testing Standard used.

If a thermal imaging camera is used to look at the outside of the glass under the same test conditions, but with the vehicle stabilized at normal lab ambient (say 20°C); a pattern appears on the glass within a couple of minutes. This pattern, once formed, does not seem to significantly vary in shape, only in intensity.