Going in, we expected the vehicles would drive conservatively and cautiously, timidly even. Instead, the driving was more humanlike than predicted, though with a strict regard for the posted speed limit. Acceleration ranged from casual to a bit aggressive, as did steering inputs. Some lane changes were casual, and some were a bit abrupt, particularly when entering dedicated turn lanes. Ludwick says the fourth-generation vans like to get over into the lane immediately while the fifth-generation SUVs are programmed to do so a little more gradually and smoothly.
Braking was almost always early enough to slow gradually and smoothly. The only exception was when the system thought a pedestrian or cyclist might be in the way. Photographer Walker triggered one van walking out behind our parallel-parked truck to get to the driver door, and a cyclist clearly in their lane and not deviating concerned the same van enough to slow down and follow the cyclist for several seconds before eventually passing.
On other occasions, the Waymos were surprisingly assertive. One saw the light change as we were approaching the intersection at 45 mph, hesitated a moment, then accelerated to make the light. Another followed a city bus that began to pull off into a stop and the van cheated to the left side of the lane to go around it rather than wait for it to pull over all the way.
Even unexpected obstacles didn't faze it. Rounding the corner in one neighborhood, we came upon a pile of gravel dumped in the street for someone's yard project. The van went right around. Late in the day, we were driving directly into the setting sun, and the Waymo was slowing for speed bumps we couldn't see through the glare with human eyes until we were right on top of them.
We needed the Costco parking lot. Cars zooming around frantically searching for open spots, people with and without cars wandering into the lane without looking, vehicles stopping in the middle of the lane to pick up bulky items, you name it. The Waymo One handled it all like a pro. It was certainly slower and less assertive than you or I might be in the same situation, but we had no emergency stops or questionable moves.
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The vehicles can recognize and follow the commands of a construction worker or police officer giving hand signals. They know how to deal with construction zones and lane closures. The company is working on enhancing body language detection to better predict what pedestrians and cyclists are going to do.
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Waymo One runs 24 hours a day without human drivers, but as soon as it rains, the humans are back in the front seat keeping a watchful eye and ready to intervene. Snow? Yeah, right: Even the fifth-generation vehicles are still learning to cope with heavy fog in San Francisco.