Citizens move between the distant parts of the city by means of a free, public transportation system. It is an ultra-light rail, featuring cars for two passengers, that move between long translucent tubes that connect the domes of the city. When one car stops at a station, its door slides open to allow exit and entry. We never see a car waiting behind another. Once seated, riders press a red button on a panel between the two seats (just visible in the screen capture below), and the car seals shut and takes off to the next station.
A small panel inside the car alerts passengers to the name of the next stop as well as any additional information that is of use. When Logan and Jessica head to Cathedral Station, the panel blinks a red light to draw their attention. (The paired green light is never seen illuminated. What’s it there for?) A female voice says "Entering a reservation for violent delinquents. Authorized persons only." The screen before them reads, “personal risk area." (For those wondering why it stops there at all, anyone can get out of their car here, but Logan has to use his personal communication device with Control to have the gate to Cathedral opened.
The panel and voice output are useful to alert riders whose attention has drifted. Text could be put in the environment of course, since this information rarely changes, but it’s a bit harder to read when it’s moving and isn’t as likely to gain a distracted rider’s attention.
The last bit of interface is the LED displays on the walls of fancier stops like Arcade (the dome with the shopping mall and Caroussel.) We never see this sign change, but it makes sense that while riders are at the station, it displays the stop as a reinforcing bit of information, and can display alternate messages for citizens waiting on a car otherwise.
The interface is incredibly simple because the system is so constrained. You have to hop on at a station, and like an airport tram or a shabbat elevator, the car runs along a fixed loop. You hop out when you’re there. The main negative issues I see are selecting a stop and perhaps safety.
Selecting a stop
It’s a waste of time and energy to have cars stopping and starting at unwanted stations. It can also be distracting to have the car tell you about all the intermediate stops when you’re not interested in them.
To solve this problem, the track system should be built with track bypasses so we have to worry less about track congestion at stops. Then riders could either ride the “local” from stop to stop, or optionally have some way to indicate their desired stop, bypassing the ones in between. What’s this indication look like? In the panopticon of Dome City, the Übercomputer can just listen to your conversations wherever you’re having them, and when you get to a car default to the stop expressed in conversation. Logan and Jessica had just spoken about Cathedral Station, so when they stepped in, it could have just asked them to confirm. If the selection was wrong, or no stop had been mentioned recently, riders should be able to speak their destination or the event to which they’re headed. As a last fallback, a screen displaying discrete options could allow them to select a destination by touch or gesture.
The safety issue is subtle, but if riders have no control over the cars, why are the seats facing forward? It’s much safer in a head-on collision to be seated "backward," like an infant’s car seat. Psychologically, people are most comfortable sitting forward to see in the direction of potential collisions, but if you lived in an UberNanny State like Dome City, the system would just force people to sit in the safest way.
It’s going to be more complicated than this
Getting public transportation experience design right is tough enough. But it’s going to get more complicated. Here at the dawn of computer-driven cars and computer-requested and computer-wayfinding "routeless" busses, the challenges will be manifold. How do you signal a stop? How does it gracefully degrade? How do you pay? How do you get to a just-in-time defined stop? How do you indicate your destination(s), willingness to share the ride, and urgency? How do you not disenfranchise people just because they have no cell phone? Dome City is small and constrained enough to ignore such problems, like a light rail in a small, wealthy, downtown core, making it almost too simple to be instructive.