Massaging seats are nothing new, but General Motors has filed an application with the United States Patent and Trademark Office for a patent on an in-floor foot massaging system.

First spotted by Carscoops last week, the document describes the use of small air bladders placed in the passenger-compartment floor. Inflating or deflating them massages passengers’ feet. That’s how current massaging seats work, so it seems GM is just looking for a new application of existing technology.

GM wouldn’t be the first automaker to offer a foot massager. The Audi A8 is already available with one, Carscoops noted, but it’s embedded in a footrest, rather than the floor. That footrest folds down from the front passenger seatback, so the function is only available to the right rear passenger.

General Motors in-floor foot massaging system patent image

That makes sense in a big sedan like the A8, which is more likely to be chauffeur driven. It’s already standard practice to leave the front passenger seat unoccupied to maximize legroom for a single rear passenger, so this seems like the next logical step. While GM hasn’t discussed any production plans for a foot massager, it has a large luxury sedan of its own in the works.

A feature like this would be a good fit for the Cadillac Celestiq, the brand’s upcoming all-electric flagship. Cadillac has already confirmed that the Celestiq will feature a four-quadrant glass roof and a massive display screen, and it will be mostly hand-built.

The Celestiq will be Cadillac’s second all-electric model, after the Lyriq SUV scheduled to start production in 2022, and part of larger plan that could see the luxury brand go all-electric by the end of the decade. That means, if future Cadillacs get built-in foot massagers, there won’t be internal-combustion engines to mask whatever  sound they might make, though GM will likely deal with that as well.

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