Each car would have required gyros, and power, and an operator...$$$$$. An idea ahead of his time.
HOWEVER - Beacon Energy makes commercial flywheel energy storage units. Using modern digital controls and paired contra-rotating carbon-fiber spinning-in-vacuum on maglev bearing Beacon off-the-shelf flywheel units, it would be relatively easy to make these trains happen. The flywheels can supply energy to operate the train when between external electrical sources and store braking energy as well. These units are self contained and about the size of a 55 gallon drum.
You live in the future. The hard part is prying off the cold dead fingers of special interests off of the throttle...