Cars that drive themselves could be on the road by the end of the twentyteens, says DEE-ANN DURBIN, but don’t take your foot off the pedal just yet.DETROIT, Michigan - Automakers, universities and others are at various stages in the development of autonomous cars but there's still a lot of work to be done before this kind of technology can be implemented. Companies experimenting with this development include Google testing driverless Toyota Prius units in California; General Motors recently announced that its 'Super Cruise' system, which uses radar and cameras to steer and stop a car, could be on Cadillacs by the end of this decade and, Nissan has boldly promised that it will have an autonomous driving system by 2020.RELIABLE TECHNOLOGYNissan CEO Carlos Ghosn said earlier at the 2013 Detroit auto show: "This is not a 'Star Wars' technology. This is a technology that’s becoming more and more reliable." There's loads of work to be done before this technology can be implemented anywhere. Issues such as laws requiring a licensed driver at the wheel will have to change, insurers will have to determine who’s at fault if a self-driving car crashes and highways will need to accommodate cars without drivers.In a recent report, consulting company Navigant Research estimated it will be at least 2035 before a majority of vehicles sold worldwide will be able to drive themselves. Navigant predicts this technology will come in bits and pieces and is already available with some modern cars such as self-parking cars, systems which help drivers navigate traffic jams and then cars that can cruise by themselves on a highway will follow - and will take some time to migrate from luxury cars to more mainstream brands.The company said in its report: "The role of the driver of a vehicle will evolve to be more like that of a pilot in an aircraft.” REALITY CHECKSAutonomous cars are moving to reality thanks to rapid advances in technology, explained the company. Lane-departure warning systems first appeared in 2003. They typically used one camera, mounted on the windshield, to warn drivers if they swerved out of a lane. Newer systems are far more complex. Now, multiple cameras and radars can detect pedestrians and avoid them by telling the car to apply the brakes. Some cameras can even read street signs.The story is similar with adaptive cruise control, which first appeared in the mid-1990s. Back then, it could maintain a safe distance from a car directly in front of it at highway speeds. Now, more advanced adaptive cruise control systems can monitor cars in other lanes, work in slower, stop-and-go traffic and even apply the brakes and halt the car.Navigant predicts future navigation systems will be able to give turn-by-turn directions to the car instead of the driver.Amnon Shashua, the co-founder of Mobileye, which writes software for automotive cameras said: "Technology isn’t perfect. There are still situations in which humans outperform computers. At a four-way stop, a driver can crane his neck, scan for traffic and quickly determine the speed of any oncoming vehicles. So far, cars can’t mimic that."