DETROIT -- Improving sensor technology, solving legal issues and getting real-time mapping and traffic information into vehicles are three roadblocks that need to be removed before driverless cars can take to the roads, a panel of experts concluded Monday.

The panelists agreed that automated driving will continue to evolve in steps.

The panel included Hideki Hada, general manager of Toyota Motor Corp.’s Intelligent Vehicle Systems; John Capp, General Motors’ director of controls and active safety technology; Steven Dellenback, director of r&d at Southwest Research Institute; Kay Stepper, Bosch’s head of driver assistance and automated driving; and independent analyst Robert Denaro.

“We’re not going to jump into fully automated driving,” Stepper said during the discussion at the 2014 Intelligent Transport Systems World Congress. “It will be a step-by-step introduction."

He said the road map to an autonomous car starts with electric steering and brakes, adaptive cruise control and lane keeping, which can then be used to allow some highway driving functionality.

“Automated driving door-to-door is a topic for next decade,” he said.

Hada said Toyota’s focus on boosting the self-driving capabilities of its vehicles is to improve safety, not to remove the driver from behind the wheel. “We have to reduce casualties by improving the cooperation between the vehicle, pedestrians and the road,” he said.

Toyota is developing sensors, cameras, radar and lidar that can “see” further around the vehicle in order to give drivers more time to react to fast-changing situations. Toyota’s goal, he said is to give drivers 5-10 seconds to react. Toyota is also working on interior cameras that monitor drivers’ faces to determine if they are in control of the car.

Capp, speaking of the Super Cruise system that Cadillac plans to introduce in 2017, said the driver will still be responsible for the car’s safety. “The technology is not to the point where the driver can be totally checked out,” he said. “The driver is still going to gave to pay attention."

Hands-off system

GM CEO Mary Barra said Sunday Cadillac plans to offer the hands-off driving system with the vehicle taking over braking and steering in certain driving conditions. Currently, automated driving technology does not work well enough in snow and on rain-soaked roads to be safe.

Capp said GM engineers are working on sensors less susceptible to bad weather. But he also said that vehicles must be connected to the cloud so that that automated driving systems can have access to real-time traffic and mapping data.

“If we know we are in space on a detailed map, we can make more use of sensors,” he said.

Stepper said once the technology is perfected, proving that it works perfectly and safely in every driving situation will be a massive challenge. Said Stepper: "The validation will have to be that your system will not have one single failure."

Dellenback compared the cost of developing the software to control self-driving cars to that of writing software for a manned space flight.

He said, “The cost of each line of software is incredible."