Mercedes' New AI-Powered Driving Assistant Could Change City Driving Forever

• The new Mercedes-Benz CLA EV debuts a new suite of autonomous driving aids.
• MB.Drive Assist Pro accelerates, brakes and steers itself with minimal driver intervention in the city.
• The tech launches for the CLA EV later this year and will appear in future Mercedes vehicles.

While I'm ostensibly here to drive the CLA EV for the first time on U.S. soil, I'm more interested in the in-depth look at MB.Drive Assist Pro — a suite of advanced driver assistance systems (ADAS) that debuts on the CLA before rolling out to future new Mercedes models. 

While most ADAS suites are designed to make highway driving easier, Drive Assist Pro takes the wheel at lower speeds. I rode along with Mercedes technicians as they demonstrated how the system works, navigating a crowded city center in various situations that even seasoned drivers would find anxiety-inducing.

What is MB.Drive Assist Pro, and how does it work?

Before we hit the street, some background. Mercedes has long offered safety features with jargony names that require a decoder and tolerance for abnormal capitalization to decipher. At its core, MB.DRIVE ASSIST PRO — as Mercedes stylizes it — includes a major enhancement to existing and optional CLA equipment. Standard on every CLA is a suite of driving aids, including Distance Assist DISTRONIC (adaptive cruise control), Lane Keeping Function (lane departure warning and mitigation), Blind Spot Assist Plus (blind-spot monitoring) and more. In human speak, these features control acceleration and braking on the highway, make sure you stay in your lane, and alert you if a vehicle is in your blind spot.

The MB.DRIVE ASSIST package further adds Steering Assist (lane centering assistance) and Lane Change Assist (one-touch automated lane changes). Upgrading to MB.DRIVE ASSIST PRO adds a single feature, dubbed "Digital Extra: Stop Sign and Traffic Light Function." As I soon learned, this generic description masks untold amounts of code, labor and corporate partnership. 

Every CLA comes with a staggering 10 cameras, 12 ultrasonic sensors and five radar sensors, all of which feed information to a central processing unit developed by Nvidia to provide a clear map of the CLA's surrounding area. Drive Assist Pro marries all this collected data with programmed logic and AI simulation to decide how the vehicle behaves at city speeds. 

The AI simulation is the really interesting part. Say the CLA encounters a scenario in real life that all the preprogrammed testing and validation has never encountered before, so the car doesn't have a defined logic well that it can draw on to determine how to behave. A circus bear in a top hat walks in front of the car, walking a cat on roller skates, for instance. 

Using Nvidia's Omniverse simulation tech, the CLA, in real time, can match that with something it has seen before — say, a human pulling a dog wearing Rollerblades — and brake or avoid the obstacle as necessary. Then this new scenario and behavior is added to the Mercedes repository and sent out via over-the-air update to other vehicles with Drive Assist Pro. 

The end result is that the CLA EV can regulate its speed and steering at low speeds just like Tesla's Full Self-Driving, and, like FSD, the necessary constant refinements to the system mean that Drive Assist Pro follows a live service model. The current package price of $3,950 is a $2,000 upcharge over Drive Assist and includes three years of service and updates. But unlike Tesla, Mercedes is taking its time to make sure the system works properly before rolling out Drive Assist Pro to users — the service won't come online for the CLA until later this year. 

Stress-testing in San Francisco

As exciting as it was to learn about how Drive Assist Pro works, the real test was to see how it performed in one of the most crowded cities in the country. Since Drive Assist Pro is still months away from release, I sat shotgun alongside a member of the team that developed the system. We began by selecting Merc's preplanned drive loop in the nav system; the total drive would last roughly 50 minutes. Because Drive Assist Pro has fully automated acceleration, braking and steering (though your hands must touch the wheel), the car needs to know where to go before it takes control, but it will follow the entire route on its own. 

The first turn is a left onto the Embarcadero, with the north and south lanes separated by a metro rail crossing. The car waited a tick after the light turned green, traversed the rail crossing, and turned into the single left lane. It would be the first of many that we completed without issue.

As we traveled up to North Beach and Fort Mason, the ride was somewhat boring — a function of both the solid tuning of Drive Assist Pro and, admittedly, the relatively light vehicle traffic during our late-morning drive window. On a few occasions, we needed to turn right at a stoplight with a No Turn on Red sign, and the CLA followed the guidance; it didn't execute the turn until the light turned green and verified that pedestrians were clear of the crosswalk. 

We also halted at a four-way stop while another vehicle stopped at the same time. The CLA waited at the stop sign for a few beats, then, when it was obvious that the other car was letting us go first, the CLA accelerated away. It all felt very natural — I was deliberately watching my driver's inputs, but if I hadn't, I would have assumed he was fully piloting the car.

The return portion of our loop crossed through Japantown and Nob Hill; with a high vehicle and pedestrian density, this is where the Drive Assist Pro logic really shone. The CLA braked for jaywalkers who exhibited little regard for personal safety, braked for vehicles darting in and out of parking spots, and changed lanes when it identified that the next lane over was less trafficky.

The most impressive maneuver was when we approached a double-parked car with its flashers on, on a road with a single lane in each direction. The CLA approached the vehicle, then crossed over into the opposing traffic lane to get around it. A car was approaching in the opposite lane, but the CLA had determined that there was ample time to execute the maneuver safely. 

Even in this pre-release build, Drive Assist Pro is very impressive. During the drive loop, the driver only intervened once to brake for a vehicle that quickly crossed into our lane close to the CLA's front bumper. If there's one thing to iron out for the release version, it's this scenario. I've found that adaptive cruise control systems often struggle to react to vehicles entering your lane, so I wasn't surprised to see that this was the condition under which the CLA "failed." 

Tightening up the logic to identify when a car is entering your lane versus merely cheating over the marker to account for a bicyclist (or because the driver simply isn't paying attention) is the only real improvement to be made. Based on my drive loop in San Francisco, this system is ready to push live. With all the care going into its rollout, don't expect to see any "look at the dangerous thing Drive Assist Pro did" videos on TikTok when it launches.