Hoof Beats? Really? At 15 MPH or less? If Mercedes-Benz can make sensors that allow a vehicle to stop short of a vehicle stopped or to maintain distance during cruising, why can't the same sensor array be used to flash headlights or the audible double honk warning prior to the vehicle stopping on it's own. For that matter, how about day/night vision that compares digitally comparative movement from outside of the planned vehicle path based upon steering position. Making noise to prevent accidents is like putting playing cards into the spokes of my bicycle, it might keep those with hearing out of the way, but what about grandma or the late night pub crawler?
I can certainly understand the need for this. I have an issue with hearing and EVs, depending upon the model, are almost "nonexistant" when unseen. In the work I do on a daily basis; i.e. gas combustion, its'a know fact that natural gas is oderless so, an oderant is added for detection. Very same principal as Charles has mentioned. The automakers are definitely following the logical path, even if my mandate.
Believe it or not, oldpartsnrust, there was a movie called "The Dilemma" with Vince Vaughn where the main characters do the very thing you've described. They develop a way to make an electric car sound exactly like an old-fashioned muscle car.
Producing high-quality end-production metal parts with additive manufacturing for applications like aerospace and medical requires very tightly controlled processes and materials. New standards and guidelines for machines and processes, materials, and printed parts are underway from bodies such as ASTM International.
Engineers at the University of San Diego’s Jacobs School of Engineering have designed biobatteries on commercial tattoo paper, with an anode and cathode screen-printed on and modified to harvest energy from lactate in a person’s sweat.
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