High-Speed IR Camera Captures Images Without Blur: Results Show Benefits Of LWIR Spectral Band

Infrared (IR) cameras can image fast-moving objects and measure the temperature of any point on an object without the errors assoc-iated with motion blur. One application is in the study of the thermal characteristics of tires in motion. Using a high-speed IR camera to observe tires running on a dynamometer at speeds in excess of 150 mph, researchers can capture detailed temperature data during dynamic testing to simulate turning and braking loads.

To optimize imaging performance for this application and minimize motion blur requires the careful selection of camera exposure time, frame rate and spectral band. This involves calculations that depend on the linear velocity of the tire, the desired spot size resolution, the anticipated temperature range and the desired thermal sensitivity.

Normal operating temperatures for tires are within the ambient operating specification of a tire, plus a factor for the load-induced heating of the tire under a wide range of load and speed conditions. For our testing, we assumed that the maximum temperature a tire would be about 70°C. Given the uniform material properties of a tire, it is assumed that the temperature resolution or sensitivity required for proper analysis of the tire under various test conditions will be <0.25°C.