Automakers have struggled for decades to make cars quieter. But in a complete reversal, Lotus is now working on making some cars louder—specifically, electric and hybrid vehicles that are almost dead silent at low speeds. AutoblogGreen has a report on the company's latest effort, the Safe and Sound hybrid demonstrator, which helps pedestrians hear the car approach.

Lotus built the system into a current-generation Toyota Prius as a test bed. The report said that instead of traditional noise-canceling, which uses internal speakers to generate opposite sound waves to cancel noise, Lotus mounted external speakers on the car with a controller tied to the accelerator pedal. The system generates simulated engine sounds that passerby can hear.

The report said that Lotus is working with the Royal Society for the Prevention of Accidents and the Guide Dogs for the Blind Association in order to develop the system.