To the uninitiated, a track day might seem like a very cool-guy sort of thing to do. Take your car out, drive like a stripe-assed ape on a closed course wearing your Räikkönen-spec safety duds, and generally act the hero. The reality of the deal" It?s much more prosaic and nerdy. Drivers geek out over lines, setup, niggling issues with their automobiles, and speak in tongues largely impenetrable, all in pursuit of a second here, a tenth there. In short, the events are packed to the gills with study, trial, and error, making them an oddly perfect venue for the percolating autonomous-vehicle startup scene. Joshua Schachter just happened to be the first guy to realize it.

Over a decade ago, Schachter created Delicious (which you may remember as del.icio.us), eventually sold the social-bookmarking site to Yahoo!, moved on to Google, and then left to re-enter the startup game both as an angel investor and with Tasty Labs, which he co-founded and eventually sold to Walmart. Schachter, then, is a guy with a name and a record of success in Silicon Valley. But if we showed up at Thunderhill?s technical West Course hoping for glorious demonstrations of spleen-torquing pilotless speed, we were disappointed.
Audi?s people brought out Bobby, one of the automaker?s autonomous RS7s, for a demonstration, but said they were doing no development work on the car at the track day. The guys from Denso, who?d hauled up a Model S equipped with an array of additional sensors by Autonomo...