Google has been working on self-driving cars for a while, but until this year the company basically bolted its equipment onto familiar vehicles.

The test cars looked almost normal: When the company did street demos, a staffer would pose reassuringly behind the (nonfunctioning) steering wheel, and the most noticeable addition was the fast-spinning, roof-mounted laser sensor that delivers 360-degree information to the car’s driving mechanism.

But in May, Google unveiled its first “purpose-built” self-driving vehicle — looking a little like a cartoon car ,with no steering wheel or pedals — and videotaped some volunteers taking an unaccompanied ride. In “A First Drive,” which you can find on YouTube, the “drivers” include some senior citizens, a mother and her son, and a blind man.

“You feel relaxed,” says a gray-haired woman who giggled through her trip pretending to turn an imaginary steering wheel. “What she really liked was that it slowed down before it went around the curve, and then accelerated in the curve,” says one man, nodding toward his wife.

And the blind man yells, “I love this!” out the window, adding later, “There is a big part of my life that a self-driving vehicle could bring back to me.”

Google’s first “purpose-built” self-driving vehicle lookS a little like a cartoon car. (Associated Press)

Chris Urmson, director of the car project, brought the video to a Washington theater last week as part of his presentation at “Fix My Commute,” a day-long program on transportation problems and solutions organized by The Post. (One speaker was Carl Dietrich of Terrafugia, whose flying car, or “street-legal airplane,” spent the day parked in front of the theater, inspiring a multitude of selfies. He said it can take off at 70 mph.)

Urmson took questions about Google’s business plan, the self-driving car’s safety and price, and production issues. Finally, he was asked when he thought his team might be ready to market a self-driving car. “My son is 11,” he said. “He’ll be 16 in five years. So the goal . . . .”

To see a video of Urmson’s Washington appearance, go to www.americaanswers.com.