In contrast, PRT vehicles have been designed for as few as one person, but more commonly four or five people, the capacity of a small car. A PRT can possibly operate efficiently with just one passenger. While monorail guide ways are typically configured for longer distances between stops, the smaller PRT vehicle allows operation on a network with multiple stations. PRT systems therefore more closely replicate the operation of the private car. The Seattle Monorail has such a drive system.
Some systems run on induction motors.
Vehicles roll on rubber wheels before levitation is achieved. Elevated systems now operating range from those under total human control to those that are fully automated. Vehicles have no human operators on board. The system can be overridden by the operators in the control center. The BART system in San Francisco has a single operator on board each train who serves as a backup safety measure.