Researchers are making rapid progress in developing systems designed to give cars ever more autonomy. The benefits are myriad; and some, like making a dramatic reduction in the tens of thousands of traffic fatalities that occur each year, are priceless. Still, automakers are loathe to add new, costly components without a clear sense of how the additions will justify a higher sales price. Researchers, keenly aware that every penny counts, are looking for ways to cut the cost of making cars smarter.