Sign up for our daily briefing

Make your busy days simpler with Axios AM/PM. Catch up on what's new and why it matters in just 5 minutes.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on the day's biggest business stories

Subscribe to Axios Closer for insights into the day’s business news and trends and why they matter

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios Pro Rata

Dive into the world of dealmakers across VC, PE and M&A with Axios Pro Rata. Delivered daily to your inbox by Dan Primack and Kia Kokalitcheva.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sports news worthy of your time

Binge on the stats and stories that drive the sports world with Axios Sports. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Tech news worthy of your time

Get our smart take on technology from the Valley and D.C. with Axios Login. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Get the inside stories

Get an insider's guide to the new White House with Axios Sneak Peek. Sign up for free.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Catch up on coronavirus stories and special reports, curated by Mike Allen everyday

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Denver news?

Get a daily digest of the most important stories affecting your hometown with Axios Denver

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Des Moines news?

Get a daily digest of the most important stories affecting your hometown with Axios Des Moines

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Twin Cities news?

Get a daily digest of the most important stories affecting your hometown with Axios Twin Cities

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Tampa Bay news?

Get a daily digest of the most important stories affecting your hometown with Axios Tampa Bay

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Charlotte news?

Get a daily digest of the most important stories affecting your hometown with Axios Charlotte

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Nashville news?

Get a daily digest of the most important stories affecting your hometown with the Axios Nashville newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Columbus news?

Get a daily digest of the most important stories affecting your hometown with the Axios Columbus newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Dallas news?

Get a daily digest of the most important stories affecting your hometown with the Axios Dallas newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Austin news?

Get a daily digest of the most important stories affecting your hometown with the Axios Austin newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Atlanta news?

Get a daily digest of the most important stories affecting your hometown with the Axios Atlanta newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Philadelphia news?

Get a daily digest of the most important stories affecting your hometown with the Axios Philadelphia newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top Chicago news?

Get a daily digest of the most important stories affecting your hometown with the Axios Chicago newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Sign up for Axios NW Arkansas

Stay up-to-date on the most important and interesting stories affecting NW Arkansas, authored by local reporters

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Want a daily digest of the top DC news?

Get a daily digest of the most important stories affecting your hometown with the Axios DC newsletter.

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Please enter a valid email.

Please enter a valid email.

Subscription failed
Thank you for subscribing!

Illustration: Rebecca Zisser/Axios

To ensure the safety of autonomous vehicles, companies have been testing fleets in San Francisco, Austin, Miami and elsewhere — gathering data and exposing their technology to everyday experiences. However, road tests are a cumbersome form of validation — the Rand Corporation estimates it would take hundreds of millions to hundreds of billions of miles (nearly a century of driving) to prove an AV drives safely.

The big picture: Not all experience needs to come from road tests. Simulation platforms enable the artificial intelligence brain powering an autonomous vehicle to run in a photorealistic world that mimics real-life traffic, exposing its deep-learning algorithms to scenarios and conditions as many times as necessary for the system to handle them perfectly.

Manufacturers can also test hardware using a process called hardware-in-the-loop, in which one server simulates the driving environment while another contains the computer that will eventually run in the car.

  • The output of the first server is the input to the second, running the same software as it would if it were driving on the road.
  • The commands to control the vehicle are then sent back to the simulator 30 times every second, completing the "loop" and allowing engineers to test the software in the same hardware environment as it would operate in the vehicle.

Human-in-the-loop testing adds another layer.

  • Engineers can take over other vehicles in the virtual environment — like cars in a video game — driving them around the AV and testing how it reacts to sudden cut-offs or tailgaters.
  • When combined with public road testing, this type of simulation creates a robust validation process in a fraction of the time it would take to drive an equivalent distance in the real world.

Yes, but: Though virtual worlds like those seen in video games and movies can closely mimic the look and feel of reality, their scripted scenarios lack the same fidelity when it comes to the real world’s diversity and unpredictability.

  • Drawing datasets from simulation partners, regulatory agencies and other sources onto a single platform is crucial for comprehensive testing. With an open platform, third-party developers can provide countless cityscapes, vehicle dynamics models and traffic scenarios.
  • The same situation can be run over and over again, with a nearly infinite number of changes each time — from time of day, to weather, to an animal crossing the road. And with the addition of human-in-the-loop testing, traffic scenarios can be improvised on the spot.

The bottom line: While scripting the infinite number of potential traffic situations may be impossible, enabling diversity and spontaneity in simulation is a vital way to test a car’s reaction to unforeseen scenarios, validating AV technology without sacrificing safety.

Danny Shapiro is senior director of automotive at NVIDIA.

Go deeper

Toyota to build $1.3 billion U.S. battery plant in North Carolina

The all-electric Toyota bZ4X, the company's first battery-electric vehicle, at the Los Angeles Auto Show in Los Angeles, California on Nov. 17. Photo: Frederic J. Brown/AFP via Getty Images

Toyota announced Monday it's investing $1.3 billion to construct an electric vehicle battery "megasite" near Greensboro, North Carolina, set to open in 2025.

Why it matters: Toyota's Prius hybrid won environmental plaudits when it launched in 1997, but it has since lost ground to electric vehicle world leader Tesla, per Axios' Joann Muller. This battery plant will be the first to produce automotive batteries for Toyota in North America.

3 hours ago - Politics & Policy

Congress hunts for shortcut to pass defense funding, debt limit combo

Senate Majority Leader Chuck Schumer returned to his office Monday. Photo: Anna Moneymaker/Getty Images

The scramble in Congress to pass the National Defense Authorization Act is being complicated by an effort to tie it to a needed hike in the federal debt limit.

Why it matters: The House and Senate are rapidly coming up against a series of deadlines they must address before the end of the year — or risk disrupting crucial military funding and upending the economy. Congressional leaders are now hoping they can knock out both "must-pass" priorities in one, complex swoop.

Scoop: Inside Jake Sullivan's call with U.S. hostages' families

Photo: Jim Lo Scalzo/EPA/Bloomberg via Getty Images

National security adviser Jake Sullivan spoke last week with relatives of U.S. hostages and others wrongfully detained abroad, after more than two dozen families expressed frustrations about their inability to get a meeting with him or President Biden, Axios has learned.

Why it matters: Participants on the video call, which began at 7pm ET Friday and lasted more than an hour, told Axios they didn't get satisfactory answers to many of their questions. Nonetheless, they were encouraged by Sullivan's commitment to follow up and pledge to be personally available to them and others going forward.