EVOLVAD All evolvAD test vehicles will feature a safety driver on board Expert input “We then do more simulation and test the software for any unexpected behavior, and then we take it onto a public road with a safety driver, where we run the software offline to compare it with what the safety driver is doing,” he continues. All of evolvAD’s safety drivers are fully qualified and have been trained to react in the event of a system failure. “If the control system of the vehicle fails, then the safety driver follows the training they have undergone previously at the proving ground, which includes acceleration or steering override,” says Shah. “There are a lot of safety checks, protocols and procedures undertaken before the vehicle can begin testing on the open road.” The team are reluctant to reveal any safety driver intervention data, at this stage: “Everything depends on what testing we are doing and the maturity of that software and hardware at the time,” explains Bateman. “However, the plan is that when we get to the end of the project there will be no intervention from the safety driver.” “THERE ARE A LOT OF SAFETY CHECKS, PROTOCOLS AND PROCEDURES BEFORE THE VEHICLE CAN BEGIN TESTING” Nirav Shah, research engineer, Nissan Technical Centre Europe Shah notes that the safety drivers are integral to the project, providing valuable input that shapes the AD software. “All the safety drivers are very well trained not just in test driving but in every aspect of driving on a public road,” he says. “They all drive like an expert chauffeur and they help us understand how the vehicle should behave from their perspective. There’s a lot of discussion and collaboration with our safety drivers as this ensures the vehicle doesn’t behave like someone driving on the road for the first time.” As to how best to solve the conundrum presented by a parked car wanting to pull out, Bateman says it’s all a matter of tuning: “If there is enough space and we want to be assertive, then potentially we could go more toward the middle of the lane, keeping enough space on the right-hand side for the oncoming vehicle to pass. In software terms, it’s not only longitudinal movement but also lateral movement, and deciding when to move laterally is very interesting in those scenarios. A lot of it is down to fine-tuning, which takes up a lot of the software engineers’ time.” Bateman notes that Nissan learned a similar lesson from the previous ServCity project: “When we first started, as the car approached a roundabout, it would slow right down to give way, even when there was no oncoming traffic, but that isn’t how humans drive – we tend to maintain the same speed if the path is clear. However, the software that first came across from Japan slowed the car down to give way before then pulling off. If you were the car behind, and you weren’t paying attention, you’d end up going straight into the back of it.” He continues, “Nirav and his team immediately began tuning the software to make it more assertive, so now it says, ‘I’m at the roundabout. There isn’t a car coming. I don’t need to slow down, I can go’. We then began to tune it to take the same ‘lane’ around the roundabout as a human would take. We used to joke that one of the roundabouts was more of a ‘square-about’ – you had to straighten up a bit, then go around a little bit and then straighten up, etc. In the end, we tuned it so rather than the steering wheel being jerky, it moved far more naturally.” Future outlook ServCity gathered 5.45m gigabytes of autonomous driving test data While all evolvAD vehicles will be equipped with 100% autonomous drive capability, Nissan is keen to stress that the project does not signal any intention to launch a fully autonomous vehicle in the UK and Europe in the near future. Instead, evolvAD fits into a wider autonomous drive research and development program that is taking place across Nissan’s R&D facilities worldwide. As such, the project’s findings will help inform future Nissan AD systems for passenger vehicles, with a focus on how the OEM can ensure its systems integrate into urban environments. The company already offers an L4-capable hands-off ProPILOT 2.0 self-driving system for use on highways under approved conditions, in certain countries. Research projects such as evolvAD will be vital in taking Nissan’s future technology to the next level, helping to ensure such systems better integrate into urban environments. 44 ADAS & Autonomous Vehicle International January 2024