Recently a team from LEVA-EU member THOR AVAS gathered to conduct another experiment and test their Acoustic Vehicle Alerting System (AVAS) product among the participants who most depend on sound sensations in this world – with blind listeners. The World Blind Union initially influenced with its appeal to the UN several years ago, for the implementation of sound in silent electric cars in order to reduce the number of accidents with their wards.
It was this step that led to changes in the legislation of the EU and the USA, and then China and Japan, where AVAS systems became mandatory for installation on all hybrid and electric cars.
The difference between THOR AVAS and other systems is its more complex and at the same time harmonious sounds, consisting not only of warning layers (high-frequency repeating signals), but also softer components, which makes soundtracks more enjoyable. Plus, all the sounds are associated with movement, speed up and down, and don’t just beep like toys.
A team of engineers, acousticians and sound designers create sounds and upgrade the system, subjecting it to various tests, including live tests, where real people help determine the visibility of an approaching electric car.
To conduct tests on the street, a stand with many sensors and microphones was assembled. Participants were seated on chairs and given remote controls to press, triggering a signal which the operator received on the main computer, collecting data about the speed of the car, the volume of the system and the distance at which people noticed the approach of the electric car. The work was carried out in different speed modes – 10-20-30 km/h – and at different AVAS volumes, but within the limits permitted by UN rule No. 138, according to which all AVAS systems must operate. Listeners also participated in tests where AVAS was completely turned off to understand the difference between the sound from the tires and the system.
The THOR AVAS team state that it is too early to talk about results, since there is still a huge amount of data processing work to be done; they will talk about it in their next report.