I average 18mph (burst of up to 30mph) on a7 mile ride and I have never been unable to hear approaching cars from behind. Do I trust my ears alone? No. But I've never been surprised by Prius, Volt, Tesla Roadster, or any other hybrid or electric vehicles. In biking events or on bike paths I can even hear approaching bicycles from behind (bike chain, wind, and tire noise). So I'm surprised that wind noise overpowers car noises for you.
It's been interesting to see all the comments about this! Obviously it's struck a nerve...and danger aside, I'm happy to see a number of people less than thrilled about the idea of noisier hybrids and EVs. There has to be a better solution.
The 1865 act required all road locomotives, which included automobiles, to travel at a maximum of 4 mph (6 km/h) in the country and 2 mph (3 km/h) in towns and have a crew of three travel, one of whom should carry a red flag walking 60 yards (55 m) ahead of each vehicle.
Backup audible warning is already implemented on most trucks, commercial vehicles, municipal vehicles, etc. That is not a bad idea; the driver has limited view, and risk is higher. But that is totally different than always on noise generators.
Last year at Hannover Fair, lots of people were talking about Industry 4.0. This is a concept that seems to have a different name in every region. I’ve been referring to it as the Industrial Internet of Things (IIoT), not to be confused with the plain old Internet of Things (IoT). Others refer to it as the Connected Industry, the smart factory concept, M2M, data extraction, and so on.
Some of the biggest self-assembled building blocks and structures made from engineered DNA have been developed by researchers at Harvard's Wyss Institute. The largest, a hexagonal prism, is one-tenth the size of an average bacterium.
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