Now, that’s something you’ve possibly never heard of, an elliptical acoustic mirror. Ford engineers used it to measure noise as well as pinpoint the source of it on the all-new Escape – specifically, on the surface of the vehicle, such as wind – in order to ensure the interior would be quieter than the previous model. As you can see from the photo, it sort of looks like a satellite dish with a microphone.
It was the first use of the technology on a Ford sport utility vehicle, and you could call its usage in the United States downright groundbreaking. However, it has been utilized more commonly by European luxury vehicle manufacturers, and even more interesting is that the science behind acoustic mirrors can be traced back almost 100 years! A precursor to radar, it was used for “listening” for and detecting enemy aircraft along the coast of Great Britain during World War I.
How the tech has evolved in the case of the Escape is that it allowed engineers to make changes to the vehicle’s shape – notably the mirrors and A-pillar – while in the early clay model phase in order to test theories and validate expected results. The work was done in the Ford Aeroacoustic Wind Tunnel in Germany. “We previously didn’t have this tool available,” said Peter Kleesattel, Interior Quietness Development Engineer. “Essentially we were able to optimize the shape earlier. In noise and vibration, the basic idea is you have noise sources outside the vehicle and you have the path.”
Preliminary data shows the new Escape will be among the leaders in interior quietness. In particular, the tuning work on the A-pillar helps ensure better noise performance in crosswind situations. Wind noise performance has been optimized through more than 160 hours of engineering. In a typical eight-hour block, more than 20 configurations can be tested, including glass, mirror sealing and door sealing.
“Previous technologies required more of a trial-and-error approach to finding the issue,” added Bill Gulker, Ford NVH (noise, vibration and harshness) Supervisor.