Even without a physical connection, a "virtual trailer hitch" would be easier to implement (I imagine, hah) than a general autopilot. The control loop would ha

Even without a physical connection, a "virtual trailer hitch" would be easier to implement (I imagine, hah) than a general autopilot. The control loop would have to reference the next vehicle in the chain, and adjust the speed to maintain a constant distance from it, as well as keep the centerlines of the two vehicles aligned. For emergency braking and other surprise situations a broadcast system would be useful.