This illustration has only two cars but more can be added depending on the density of that specific city. Each car is self propelled via electric motors situated near the wheels, this eliminates the need for a locomotive or main propeling car, which would only add unnecesary weight.
Similar to any other train car, the wheel assembly can swivel to acomodate turns on the tracks,
The cars should be made of a very lite material, like aluminum or carbon fiber, and steel should only be used in the wheel assembly area, this is to save weight. Is important to note that as a safety measure, moving between cars is not possible unless there is an emergency, in which case the driver will open those doors. The Articulation to link the cars is doubled above and below so that there is more support when moving and hosuld not interfere with the movement of passengers between cars.