The accident is the first time an autonomous vehicle has been to blame for an accident.
The Santa Clara Valley Transportation Authority released the video today, which shows camera angles from both outside and inside the city bus throughout the accident. The videos don't show a great amount of detail, but they give the viewer a good idea about how the collision occurred.
The Feb. 14 accident happened on El Camino Real, a wide boulevard consisting of three lanes in each direction that runs through Google's hometown of Mountain View, Calif.
According to a DMV accident report, the Lexus RX450h SUV controlled by Google's AV technology moved into the center of the right-hand lane and was struck by a city bus that was traveling about 15mph.
While the Lexus had a safety driver in it, the vehicle was in "autonomous mode" at the time. Just before the accident, the car was driving in the right lane toward an intersection and had signaled for a right turn. Sandbags surrounding a storm drain caused the vehicle to move left into the center of the wide lane.
The company said testing on El Camino Real has helped it learn to navigate "a busy and historic artery," but "on Valentine's Day we ran into a tricky set of circumstances on El Camino...."
Most of the time, Google's AVs drive in the middle of a lane but "when you're teeing up a right-hand turn in a lane wide enough to handle two streams of traffic, annoyed traffic stacks up behind you.
"So several weeks ago we began giving the self-driving car the capabilities it needs to do what human drivers do: hug the rightmost side of the lane. This is the social norm because a turning vehicle often has to pause and wait for pedestrians; hugging the curb allows other drivers to continue on their way by passing on the left," Google said. "It's vital for us to develop advanced skills that respect not just the letter of the traffic code but the spirit of the road."
As the SUV approached the turn, it detected the sandbags, forcing it to stop. After waiting for other vehicles to pass, the car -- still in autonomous mode -- began angling back toward the center of the lane at about 2 mph. That's when it crashed into the side of the bus.
"Our car had detected the approaching bus, but predicted that it would yield to us because we were ahead of it," Google said.