The recent Consumer Electronics Show in Las Vegas featured a number of carmakers showcasing their vision of the future – a future that they think will feature autonomous or self-driving cars.

But are they getting ahead of themselves? Will autonomous cars really be on our highways in the coming years – and, if so, when?

The alphabet soup of technology

The autonomous cars of the future will be largely based on technology that is already available in many of the new cars currently on sale.

Most of these technologies use radar and lidar (light detection and ranging using lasers) sensors and cameras to detect other vehicles (and, sometimes, pedestrians or wildlife), which then send this data to other systems in the car.

The types of systems you might already have in your car include adaptive cruise control (ACC), which minimizes rear-end collisions by maintaining a constant speed and distance to the vehicle ahead; autonomous emergency braking (AEB), which detects obstacles in the road and alerts the driver, braking the car if they don’t respond; blind spot monitoring (BSM), which warns of vehicles on either side that would prevent a safe lane change; and traffic sign recognition (TSR), which recognizes road signs and relays the information to the driver – or, potentially, the car itself.

All these systems are already fitted in millions of cars around the world – the job now for the automakers is to add more computing power on-board (along with more accurate mapping and GPS) in order get them to work together.

Taking it to the next level

Cars are rapidly becoming more advanced, with engineers using a system of levels of autonomy designed by the Society of Automotive Engineers. Ranging from Level 0 to Level 5, automotive technology is allowing the software and hardware experts working for the car manufacturers to climb the ladder pretty quickly.

Their focus is largely on Level 3 autonomy at the moment – which means that the driver is still necessary, but the vehicle can take over “safety-critical functions” under certain conditions, per the NHTSA’s Statement of Policy Concerning Automated Vehicle. Additionally, according to the NHTSA, Hyundai has just trialed a Level 4 car (an Ioniq, with some extra sensors on-board) on the streets of Las Vegas, which is “fully autonomous” and “designed to perform all safety-critical driving functions and monitor roadway conditions for an entire trip.”

The ultimate aim is Level 5, which won’t need any human interaction – even off-road.

On sale now

There are a number of models that buyers can choose from that have self-driving or piloted functions on-board,

The best known are probably the Tesla Models S and X. Much has been said in the media about the Autopilot function, and cases of supposed failures have been well documented. However, it’s fair to say that the California-based carmaker is attempting to lead the way in this field.

Another leader is Volvo, which has a suite of technologies it calls Intellisafe – fitted to its XC90, S90 and V90 models – that include all the electronic safety technologies mentioned above and, depending on the model and the options available, can offer some limited autonomy.

Limited autonomy is also offered in the flagship models from BMW and Mercedes-Benz, the 7 Series and S-Class respectively, and in the Infiniti Q50. The all-new Audi A8 – due in time for MY18 – will also have autonomous features.

These functions will gradually filter down to less expensive models in the next few years, certainly by 2020-2025.

So when exactly will this autonomous future arrive?

There are some pretty major hurdles to overcome before we can look forward to driver-free commuting, not least of which are the hugely complex legal obstacles and questions of liability in the event of a collision, not to mention the not-inconsiderable task of winning the trust of drivers.

The technology part is actually relatively easy compared to the aforementioned issues, and we can expect car manufacturers to have models on sale with advanced self-driving features by the end of the decade.

Beyond that, who knows? The lawyers and lawmakers will take their time, then the public will also approach autonomous cars cautiously.

But within 20 years, our major cities could be filled with cars making decisions for themselves, with their occupants relieved of the burden of driving to spend their time more productively.

Now isn’t that a vision of the future to look forward to?