Self-driving car has 13 crashes

Google will start to issue monthly reports on its self-driving cars, part of a push to disclose more information about the technology, following a second accident for one of the vehicles in less than a week.

The new reports summarise the project’s activity, data points and any incidents involving the cars, Google said. An autonomous vehicle was rear-ended at a stoplight in Mountain View, California, last Thursday.

The previous weekend another unit was hit in the same city. There have been 13 accidents since the project began six years ago, but none has been the fault of the vehicle itself, the company said.

‘‘We’ve made a lot of progress with our self-driving technology over the past six years, and we’re still learning,’’ the company said in its report for May, which includes data from last week.

‘‘Every day we head out onto public streets so we can keep challenging and refining our software.’’

Google is making its case for driverless cars with more transparency amid questions about the progress of the programme, which is part of the company’s X research lab.

The company also is using the website to explain how the technology works, gather information and give updates, Google said. The information hub makes the argument that robotic cars could help address the deaths caused by human- driven vehicles today.

As part of the reports, Google plans to give examples of situations encountered.

The latest submission includes a photo of its self-driving vehicle stopped at a light and waiting after it turned green because an ambulance was approaching the intersection.

‘‘I’m very proud of the record of our cars,’’ co-founder Sergey Brin said. ‘‘Our goal is to beat human drivers.’’

One shareholder at last week’s annual shareholders’ meeting, John Simpson, had some hard questions about the self-driving car programme.

Simpson, 67, works for a nonprofit called Consumer Watchdog, where he directs its Privacy Project.

He asked Google if it would pledge not to use any customer data it gathers from driverless cars for marketing purposes. David Drummond, the company’s general counsel, ducked the question, saying it was too early to make any such pledge.

Simpson also asked Google to release the accident reports.

During the six years Google has been working on self-driving technology, its cars have been taught to understand how to traverse the roads.

With their combination of robotics, sensors and computing power, they know how to anticipate all problems drivers face.

Using retrofitted Lexuses, Google has driven 1 million miles autonomously.

More recently, it has built several dozen small cars without steering, wheels and brakes and is ready to test them in the streets of Mountain View.

Google’s self-driving car is all set to go it alone on California’s roads.