He's the deputy director for technology services at the San Francisco County Transportation Authority (a city agency that's sort of like Muni's cousin, twice removed), and he oversees Cycletracks.
Remember Cycletracks? It's an iPhone/Android app that made big headlines a year ago. You open it when you start your ride, and close it when you reach your destination. Then it sends your route to the city, so it can crunch the data and figure out how cyclists behave and where bike improvements should go.
With Cycletracks now in its second year, we wondered how it's been working out.
"In the initial data collection we did, we got about 15,000 bike trips from 500 different people," Charlton says. "Our primary question was what kind of trade-offs cyclists make when they decide what streets to travel on."
In other words, are you willing to pedal out of your way for a bike lane or for flatter ground?
As it turns out, the answer is yes. Cyclists will go out of their way to avoid hills. And interestingly, the data shows, female cyclists are more likely to do so then men. Make of that what you will.
It's no big surprise that bikers hate hills.
"Instead of just hunches ... now we have actual data to back up our decision-making," Charlton says. "It gives us a lot of cover for policies that we think would encourage bicycle use. ... The next step is to use this info to prioritize or advocate for facilities that are not on the ground yet."
When you feed your trip into Cycletracks, it enters a strange and wonderful ecosystem of algorithms and analysis. The SFTCA uses transportation-modeling software called SF-CHAMP to predict how changes to city infrastructure will affect your commute, and now for the first time it can microtarget bike traffic patterns.
For example, SF-CHAMP doesn't know anything about the Wiggle, and yet when it looked at Cycletracks data, it was able to create a forecast for future bike trips that perfectly aligned with the Lower Haight bike route. "It was amazing," Charlton says. "We gasped when we saw it."
Although ridership goes down somewhat during the colder months, Cycletracks is still live and still sucking up data. Charlton is looking forward to figuring outphase two, which will probably allow them to compare data from summer 2010 to summer 2011.
That'll provide an important benchmark, since summer 2010 was prior to the lifting on the bike injunction. With this comparison, the city will gain important insight into how cyclists' routes have changed since new bike lanes and racks have been implemented.
Cycletracks cost about $75,000 to create, and Charlton estimates that a second phase would cost about half that. But planning hasn't even begun yet, so it's still very much up in the air.
Meanwhile, the idea has caught on across the globe. The SFCTA has fielded inquiries from San Mateo, Austin, Arlington, Boston, San Antonio, and Brisbane. The program is open-source, so any city is free to whip up its own flavor of Cycletracks and put it to work.
The long-term benefit is huge, Charlton says, particularly when pushing for improvements to the bike network: "A lot of people want to know if putting this stuff on the ground makes a difference. There are a lot of people who think that there are negative impacts to this. ... It'll be really nice to have a real way to answer those questions definitively."