How can we increase the safety of electric vehicles at lower speeds?
Mobility is getting electrified. Global electric car sales have more than doubled to 5.1 million in 2018, up from 2 million from the previous year. With battery costs plummeting, 2022 promises to be the tipping point when Electric Vehicles (EV) will cost the same as their traditional counterparts. Consequently, with EVs going mainstream, it is essential to assess their impact for mainstream use.
EVs don’t “sound” like a normal vehicle. In fact, they don’t sound like anything. EVs are notoriously difficult to hear— particularly when traveling at lower speeds. Due to the silent nature of their powertrain, EVs and Hybrid Vehicles (HV) lack the sonic feedback on speed and rate of acceleration that we have grown accustomed to hearing. This not only kills the thrill of hearing a v8 car engine revving up but even more critical, the silence becomes extremely dangerous. Pedestrians such as the elderly, children, visually challenged, cyclists and guide dogs who depend on auditory cues from vehicles, will not get any. Research shows that EVs and HVs are 40 percent more likely to be involved in an accident with a pedestrian. As a result, legislation is underway globally. The European Union is mandating that EVs be equipped with an Acoustic Vehicle Alert System (AVAS) that makes a continuous audible noise. The U.S. Department of Transportation also followed suit with a deadline of September 2020.
Equipping an EV with sound makes it safer and more exciting
How do OEMs add “audibly safe” sounds to the EV or HV to comply with regulations, while ensuring that an exhilarating engine sound is produced?
“Given the ever-increasing number of hybrid and electric vehicles on our roads, the risk to pedestrians, cyclists and vulnerable groups has risen exponentially over the years. Technologies such as HALOsonic offer an affordable and effective way of increasing pedestrian awareness of an approaching EV in noisy urban environments.” - Rajus Augustine, Senior Director, Global Product Management - Car Audio, Harman
An ideal solution to synthesize the engine sound would be able to analyze the guiding signals from the electric motor that indicate the engine status and generate engine harmonics. After this, a natural characteristic (and possibly an OEM customization) can be added to the targeted sound. This specific, electronically-generated sound can give an early warning to pedestrians that a car is approaching, while still being unique and energizing.
In Practice: Electronic Sound Synthesis for a Safer and Cooler Car
Internally, sound contouring is used by creating speed-acceleration, and throttle-dependent sounds through the standard speaker system. Moreover, the OEM can customize the “sound signature” to differentiate their brand/model and the driver can personalize it further by selecting different modes such as normal, moderate and sporty engine sound.
Externally, the Electronic Sound Synthesis technology creates a specific electronic sound, projected from speakers at the front and rear of the vehicle—providing an early warning to pedestrians that a car is approaching. The volume and sound characteristics are optimized for urban environments where the risk of collision is much higher.
Most importantly, this system delivers improved engine feedback, meets governmental safety regulations and makes drivers feel connected to the car they drive.
Andrew Kork from CNET recently visited the HARMAN R&D facility in Novi, Michigan to experience EV Electronic Sound Synthesis on the road. Watch the video below to see how the Tesla Model S can get a V8 rumble.
For today’s consumer, safety and personalization are pivotal differentiators, and with Halosonic, HARMAN has combined both from the unique vantage point of sound.