Doug Crocker knows a thing or two about driving. The 74-year-old former Hartford police officer and his wife have navigated the continental U.S. three times in their motor home. Even experienced drivers feel the effects of aging when behind the wheel. “It’s harder to turn around now to look for blind spots,” he said. “Backing up is a real issue too,” especially when he drives the Jeep they tow along for in-town use.