text: Driverles cars have been on the road to progress for a number of years. They have been upgraded to figure out what does and doesn't work. For example, in the text it says, " For example, in the late 1950's, General Motors created a concept car that could run on a special test track. The track was embedded with an electrical cable that sent radio signals to a receiver on the front end of the car." It also says, " These smart- road systems worked surprisingly weel, but they required massive upgrades to exisiting roads, something that was simply too expensive to be practical." This evidence shows that the driverless cars have been tested and improved throughout the years.