The test is performed on different kind of snow platforms making the test vehicle brake from 45 km/h to standstill with ABS activated. Speed and distance are measured by a GPS-based device equipped with optional sensors like a brake switch, accelerometers or wheel speed sensors. The braking distance and the deceleration are plot every 5 km/h in order to clearly identify the different design contributions to the snow braking overall performance (snow indentation and adhesion). It is also calculated the distance and deceleration between 40 and 20 km/h in order to fit with the most common snow braking metric excluding the influence of the brake pressure build-up time and the car ABS logic at low speeds. A deep data analysis to recognize the ABS logic impact and its matching with the tires characteristic is also possible. Test is usually done on new snow without the necessity of conditioning before starting the test. The test starts with the control tire set to be re-tested at the end of the session in order to keep into consideration possible changes of the test conditions. Up to 7 brakes are measured for each tire set and the average deceleration is considered for the overall result (expressed in %).
