Skip to content

How Nissan used his driver to cut the traffic jams

    An image that shows how Nissan's cooperative congestion management works

    A graph that shows a reduction in the braking event with Nissan's cooperative congestion management

    Instead, CCM works by having a lead car or 'probe', send information to following CCM-outsight cars, which are separated by non-CCM cars in between. The information from the probe car lets the following cars hold a suitable distance from each other – between 30 and 60 seconds – and if there is a delay, the following cars will slow down in the course of time, so that the type of Concertina campaign is prevented from activating the Traffic Onderjames when human drivers see someone delaying for them.

    Jerry Chou, a senior researcher at the Silicon Valley Center in Nissan, described CCM for me as “mixed autonomy – that means a mix of the controlled vehicles and other people driven by people in between.” Instead of DSRC, the cars use their embedded LTE modems to communicate via the cloud of Nissan.

    Like most people who have used adaptive cruise control, if your next distance is too large, other drivers will often cut in, causing you to delete. “So we spent some time balancing this phenomenon and the performance of our system. So there are some parameters that we continue to control to balance this,” said Chou.

    The view from a Nissan Ariya equipped with an experimental congestion management system.

    Note the test equipment that is mounted on the dash of this CCM-Uitste Nissan Ariya Test Vehicle.


    Credit: Nissan

    Then I asked Chou what percentage of cars in the traffic CCM-Intenscheld should be to achieve a reduction in congestion?

    “So in our simulations we have tried different penetration speeds … And we saw that our benefits increase proportionally to penetration speeds. But we can already see some good results with a penetration of around 4-5 percent,” Chou said. “But you know, that is actually a challenge of experimental. Since our experiment has only a few cars, we have thought about how they can only control these few cars to see some results.”

    Future refinements for the system include giving people some feedback about why their cars slow down (partly so that they do not encounter the system and simply accelerate manually). If that turns out to be successful, we can even license CCM to other car manufacturers in the future, Chou said.