"Upon impact with a pedestrian, the coating is broken exposing the adhesive layer," read patent paperwork dated May 17 and listing the applicant as Google.
"The adhesive bonds the pedestrian to the vehicle so that the pedestrian remains with the vehicle until it stops, and is not thrown from the vehicle, thereby preventing a secondary impact between the pedestrian and the road surface or other object."
Google reasoned in the patent application that pedestrians hit by cars typically suffer further injury by being knocked or hurled to the pavement or other objects. Self-driving cars could hit roads within five years, the head of Fiat Chrysler Automobiles said earlier this month, shortly after the company announced an alliance with Google parent Alphabet.
Chief executive Sergio Marchionne declined to disclose financial details of the partnership or a timetable for building minivans that will expand the Internet company's test fleet of autonomous vehicles.
"It's not sort of 'pie-in-the-sky,' the thing is real and it's coming," Marchionne said.
"People are talking about 20 years, I think we'll have it here in the next five years."