Nissan has taken a leading role in the European Union-funded project 'eVADER' - to create an audible pedestrian alert system for electric cars.
With vehicles driven in electric mode, either hybrid or pure electric vehicles considerably quieter than combustion engined cars, they constitute a safety hazard for pedestrians and bicyclists in traffic. The eVADER project was founded to tackle the problem, with the help of many partners alongside Nissan including Renault, the Peugeot Citroen group and Continental tires to name a few.
In a move to assist pedestrian recognition of electric vehicles (EVs), Nissan has collaborated in the creation of a potential next generation pedestrian alert technology which produces effective and targetable audible cues to alert vulnerable road users to the presence of a nearby EV, whilst having minimal impact on noise pollution levels.
Pedestrian alert technology is currently a hot topic, as growing sales of EVs have led to discussions over the pros and cons of quiet EVs. The low sound levels have been heralded as a strong benefit, as they could contribute to a drastic reduction in noise pollution.
In 2010 Nissan introduced its LEAF - the first mass-market, all-electric EV - which has Approaching Vehicle Sound for Pedestrians (VSP), fitted as standard equipment. As a leading partner in the eVADER project, Nissan drew on its EV expertise to integrate the range of technologies provided by other consortium members and Nissan into the demonstration vehicle, and worked to ensure that the sounds created were clearly audible, whilst having as little impact as possible on ambient noise levels.
The sound created not only had to be directionally beamed at targeted pedestrians, it also had to keep annoyance levels to a minimum. Siren-like noises were ruled out at an early stage, as they were found to be irritating, loud and, in some cases, emotionally upsetting to other road users.
The final version of the system features a camera built into the windscreen, which is programmed to recognise pedestrians, cyclists and other road users. On detection of a road user, six loudspeakers directionally beam sound at the target to alert them of the presence of the EV. The sound is up to five decibels lower than the sound of a conventional petrol or diesel engine vehicle. Nissan then built this system into a LEAF for real-life trials, and the vehicle was used to showcase the completed alert system at a concluding event in Barcelona in December 2014, where it was well-received by the visually-impaired community.
David Quinn, Nissan's e-VADER Project Leader said: "Pedestrian safety is of the utmost importance to Nissan, which is why we already have a pedestrian alert installed in our EVs as a preventative measure. As leaders in the EV market, we were keen to use our considerable experience to examine possible systems for future development in this field. Our objective has been to find an optimum balance between ensuring the cars are detectable, whilst retaining the reduction in noise pollution, which is one of the great benefits that our EVs offer."
The research and results collated from this project form reference material for future research into this area, and it is likely that it will be utilised to shape future EU legislation on EV pedestrian alert sounds.