The billionaire offered a demonstration Thursday night at an event titled "We, Robot," showing off 3 new products. The first was the brand's driverless Cybercab, which Elon rode into the event ... and attendees were able to test out.

He said ... "The autonomous future is here. We have 50 fully autonomous cars here tonight. You’ll see model Ys and the Cybercab. All driverless."

Specifically, 20 of the fully autonomous cabs -- that notably have no steering wheel or pedals -- were on hand at Warner Bros. Studios, where the high-tech event took place.

Elon says the cabs will be available just before 2027 and claims it will sell for under $30K.

Tesla's Optimus "personal assistant" robots were also in attendance, serving drinks and interacting with guests ... making the whole thing feel like something out of "Westworld." He even said the robots could "babysit your kids."

But, it seemed Tesla's new 20-person "Robovan" really made a splash ... as the massive driverless vehicle was a surprise at the event.