Future AirPods may include pressure sensing features. Apple has filed for a patent (number 20180367886) for “pressure sensing earbuds and systems and methods for the use thereof” with the goal of making better-better-fitting earbuds.
Per the patent filing, the AirPods can include one or more pressure sensors to determine the size and shape of a user's ear. The pressure signals can be relayed back to a processor, which may use them to dynamically optimize the volume levels delivered for frequencies over the audible range for a particular user.
Apple says that pressure sensors may be employed in a testing environment to determine the best size and shape earbuds for the general population in terms of fit and frequency response or to build a library of aural profiles. An aural profile can be a data file including an ear size and a measured frequency response for a particular earbud.
For example, a number of different earbud shapes can be tested over a large population to determine which earbud shapes provide the best fit and frequency response for the largest population set. As another example, one particular earbud can be tested over a large population. Pressure signals corresponding to each user's ear size can be recorded along with the frequency response for each earbud and combined together in a data file to form an aural profile.
Of course, Apple files for — and is granted — lots of patents by the U.S. Patent & Trademark Office. Many are for inventions that never see the light of day. However, you never can tell which ones will materialize in a real product.