Setting aside that an amateur probably shouldn't be doing this kind of testing in his driveway, this does demonstrate why full-function autonomous vehicles will need an array of different types of sensors with the data fused together. Each sensor type has different characteristics and limitations. In order for an autonomous control system to function across the wide range of real world conditions (that is beyond sunny california) they will need lidar, radar, ultrasonic and camera sensors along with V2X communications
http://jalopnik.com/guy-tests-tesla-autopilot-sensors-on-a-child-because-wh-1764501199
As far as autonomous driving goes, it’s still a bit of a freaky concept for most of us—whether we can trust the cars to detect objects, stay in their lanes and, oh, not kill us. In a test of the autopilot sensors on the Tesla Model S that included things from stuffed animals to kids, a YouTube user found some odd results.