Don't start planning for your self-driving commute anytime soon. Human drivers are still very necessary as a recent road test for five cars' driver-assistance features showed.

The vehicles, 2017 BMW 5-series with "Driving Assistant Plus," 2017 Mercedes-Benz E-Class with "Drive Pilot," 2018 Tesla Model 3 and 2016 Model S with "Autopilot" (software versions 8.1 and 7.1, respectively) and 2018 Volvo S90 with "Pilot Assist," were put through their paces as part of a Insurance Institute for Highway Safety, or IIHS, road test.

The results weren't so grand. In tests for adaptive cruise control, or ACC, in four different scenarios and lane-keeping on three hills and three curves the cars did much better on tracks than out on the road. Only the Tesla Model 3 stayed within the lane on all 18 trials for lane keeping.

Here were the lane-keeping test results:

The Model 3 and the Mercedes performed best. Image: iihs

The weaknesses of these semi-autonomous, Level 2 (meaning the car can steer itself and control its speed and distance from other cars, but humans still need to pay attention and alert in the driver seat) cars mean we have a long way to go before full autonomy. This is an indicator that these computer-controlled features are helpful and can work well, but only in some conditions.

Shaoshan Liu, founder of PerceptIn, a visual intelligence company focused on robotics and autonomous vehicles, sees the bad results on the road as yet another reason for standardization in autonomous vehicle testing.

In a phone call he said, "We're on the right path, but not there yet." As the cars showed, it's much different driving in different environments. It's one thing to be able to handle a dry dessert road, but then head to a crowded Fifth Avenue chaotic thoroughfare. Even with such different scenarios for cars to master there's no standard regulations or benchmarks to certify when a car can use these driver-assistance features or go even more autonomous.

Liu says it's still more than five years away until we can see a large scale deployment of more robust autonomous vehicles driving around.

Those fantasies of sitting on your phone while the car does everything will stay fantasy for now.