https://phys.org/news/2018-10-electric-cars-hazard-people.html "Electric cars are good for the environment – but not for people who cannot see. They have problems detecting the silent vehicles. However, Norwegian research scientists are working on a solution" Disappointingly their solution is to add artificial noise. Not very imaginative and not a good solution for reducing noise pollution. I thought of a better solution the first time I heard about this problem. Use a short range radio signal that is inaudible to all but can easily be converted into an audio signal for blind people. With the right tech you could possibly even and in direction and speed notification. I can't see why that would not work and all you would need is a little device or your phone to use the system when you get to a road.