If you find it hard to drive in a thick fog, you may not be too hard on yourself as even self-driving cars with the latest and greatest in tech are also struggling with the same task. The fog of San Francisco is proving tricky for five Waymo autonomous cars, which, as reported by Digital Trends, suddenly parked on a residential street.
In an apparent cautionary move, other Waymo test vehicles halted in the media of the street. This led to a traffic buildup as other drivers could not get around them. The traffic persisted until the fog cleared up, and the Waymo automobiles resumed their wanderings.
Waymo confirmed the incident, saying in a release that “multiple Waymo vehicles in San Francisco encountered very dense fog and determined they should pull over temporarily.”
San Francisco is legendary for its fog. Waymo wrote about it years ago: “The low-hanging clouds are iconic to the city, but they also pose several challenges for drivers, both human and autonomous. Fog is finicky — it comes in a range of densities, it can be patchy, and can affect a vehicle’s sensors differently.”
Waymo also talked about how the fog affects their technology, “Sometimes, we see fog thick enough that it deposits tiny droplets on surfaces, like our optical sensors, while other times its microdroplets just form on our sensors, impacting how far one can see. Fog can also trap other particles, such as smoke from wildfires or pollution from gasoline, creating a more opaque fog or smog that’s hard to see through.”
The autonomous cars reportedly use microwaves to see through atmospheric conditions like fog and mist and use a cleaning system to keep the sensors clean enough. However, the two apparently failed when the cars found themselves in the fog.
The latest incident may help San Francisco’s case as it tries to slow down Waymo and Cruise’s expansion following multiple incidents. Waymo has finally parted ways with its Chrysler vans, replacing them with all-electric Jaguar I-Paces.