CALGARY—Transit users want it all: Buses that are on time, not too early or too late, and non-stop rides so they can get to their destinations as soon as possible.

Now PhD candidate Willem Klumpenhouwer, who is studying transportation at the University of Calgary's Schulich School of Engineering, is trying to use math to craft efficient transit routes that also keep passengers happy.

Since about the 1970s, transit agencies have used the idea of time points, Klumpenhouwer said. These are predetermined places where a bus driver will stop and wait until their scheduled departure time arrives before continuing if they are running ahead of schedule.

Typically, transit manuals say these stopping points should be placed every seven to 15 minutes along a bus route, and that’s the case in Calgary, Klumpenhouwer explained.

But is it actually optimal? For his PhD dissertation, he set out to find out. He created a mathematical model to describe how buses behave using a physics principle called Brownian motion.

“It’s a really useful mathematical way to measure random stuff,” he said. “Essentially, as the bus hops from stop to stop, it wiggles around the schedule. I translated that to some math.”

He designed the math with specific goals in mind: minimize the cost of running buses per hour, limit the time people spend waiting for the bus and waiting at stopping points, and have buses show up as close to their scheduled times as possible.

By using Calgary transit’s own total operating hours and budgetary numbers to calculate how much the agency spends per hour, Klumpenhouwer calculated it could save a conservative $3 million per year. He said he accomplished the savings by moving the stopping points around and shaving a few minutes off of each bus route.

“In the model, I ended up being able to reduce the cost, especially operational cost, by a fair bit,” he said.

“The (best) strategy might not be to do (these time points) every seven to 15 minutes. It might be better to focus on very specific areas where there are lots of people getting off and on,” he said. “You don’t need to space them out, you can use them more frequently.”

Klumpenhouwer said his numbers work in a theoretical setting. But it’s unclear how the theory would work in the real world, with its unpredictable obstacles like traffic and unforeseen delays. But he’d like to do a pilot project to test how the math would work on an existing transit route.

Councillor Shane Keating, chair of the city’s Standing Policy Committee on Transportation and Transit, said math and real life are very different.

“Many times theoretical mathematics sounds great until you try and implement it and it doesn’t work worth beans,” said Keating. “Anything is worth a look … nothing is wrong with trying it, doing a pilot on one or two routes to see if it makes any difference.”

Loading... Loading... Loading... Loading... Loading... Loading...

Read more about: