Don't you hate bunching buses?

In this photo, 3 buses from service 240 have bunched up!

Bunching buses - a term used to describe buses that (somehow) end up traveling together, even though they may have left the bus terminal/interchange at regular intervals. Ideally, buses that leave the bus terminal/interchange at regular intervals should keep their "spacing", so that buses arrive regularly at the bus stops (and passengers don't complain about irregular buses!).

In my Simutrans world, I have found out that when I simply let the buses run, they will end up bunching. And so the first bus is constantly packed, and the buses behind sometimes run empty (and this is unprofitable!). Therefore I had to come up with possible solutions to get the buses to keep their "spacing" between each other.

Screenshot showing the bus route that is the focus of this post

The bus route in detail. Note the first stop is an interchange and provides connections to the MRT network, and the 8th stop, the terminal stop.

One solution that I came up is applied to one of my (many) bus routes, shown in the screenshot above (with highlights showing the bus route and stops). What I did was to add a minimum load criterion for the terminal stop (8th stop in the route details), as well as a maximum waiting time (after which the bus will leave for the next stop, regardless of its load); what this meant is that buses will leave the terminal stop at regular intervals.

This measure was used with great success, and buses now run at regular intervals along the entire route. I am currently working on using this approach on other routes, but there are some significant problems:

• Most of my bus routes loop somewhere, unlike this example where buses simply run back and fro along a fixed route. This means that there are problems in deciding where the "terminal" stop should be, since there really isn't a terminal stop to begin with! Nonetheless I am experimenting this approach with some routes that loop somewhere, and hopefully I can get buses to run more regularly along the routes with loops.
• There is a need to monitor and adjust the maximum waiting time so that crowds of passengers don't build up at the interchange stations!

Coming soon, another post on the design of bus routes in the cities!