Masayoshi Son has long prided himself on his ability to detect big shifts in technology early on. During his four decades leading SoftBank, a free-spending Japanese investment group, the billionaire has made some spectacularly successful investments. And some epic flops.

In recent months, Mr. Son has been laying out plans for a new big bet: self-driving cars.

Befitting his maverick approach, Mr. Son’s pitch does not resemble other efforts to develop autonomous vehicles. He is trying to convince automakers from around the world, rivals under most scenarios, to work together to use artificial intelligence to accelerate autonomous driving advances. That way, the thinking goes, they will be able to overcome the challenges that have led some to abandon self-driving car efforts.

In recent months, Mr. Son, 66, has summoned automotive executives to a tatami-mat-floored room at the top of a skyscraper in Tokyo Bay to discuss the idea, including the chief executives and autonomous-driving leaders of Honda Motor and Nissan Motor. He has also spoken with the chief executive of Uber.

Mr. Son’s vision is to assemble a group of auto companies across the United States, Japan and Europe that would pool resources, including the vehicle-driving data crucial to autonomous-driving systems, according to five people briefed on his plans who were not authorized to speak publicly.

Most driverless car projects today rely on high-definition maps to help vehicles navigate, but these maps can become outdated, and vehicles are restricted to operating only in certain areas. Mr. Son is pitching a model in which cars can navigate — potentially anywhere — using a powerful A.I. computer system that would guide vehicles through everything they encounter on roads. That system would need to be trained using massive amounts of data.

Spokespeople for SoftBank, Honda, Nissan and Uber declined to comment.