August 28, 2018 was “Observation Day” for the Trafalgar Bike Path in east London, Ontario. This was the day that Gorski Consulting set-up 10 video cameras and documented the speeds of cyclists going up and down the slope from the north side of the new CN bridge to Trafalgar Road. The path had been previously marked at 25 metre intervals and the cameras were used to observe as cyclists passed the painted markers. Later analysis of the timecode of the synchronized cameras led to the calculation of the time that a bicycle travelled from one marker to the other. As an example if a cyclist took 3 seconds to travel the 25 metres from one marker to the next this meant that his average speed was 8.33 metres per second. By multiplying this value by 3.6 we transfer this into km/h, or 30 km/h.
View of a GoPro camera anchored to the railing of the CN bridge to document the speed of cyclists travelling up and down the slope of the path.It becomes a simple process to tally up the motions of each cyclist in a spreadsheet and this provides an indication of the variance in speeds with maximums and minimums.
The slope of the path needed to be determined and that was measured on a previous day.
The table below shows the measurements of the slope of the path from the CN bridge to the terminus of the path at Trafalgar Road.
The observations of the cyclists on August 28, 2018 led to the creation of the table of speeds shown below.
The “Bridge to 10m” refers to the 10-metre section of the path at the north end of the CN bridge which is the portion shown in the second photo (above) in this article. The observation distances go as far as 175 metres north while the terminus of the path at Trafalgar Road is approximately 325 metres north of the CN Bridge. The observations of cyclist speeds could not be followed all the way to Trafalgar Road because it was impractical to stretch the camera positions over such a long distance. Rather it is expected that addition testing will be performed on another day to capture the cyclist motions for the remaining distance from 175 to 325 metres.
The purpose of this testing is to explore how a steep downslope can affect the speed of cyclists. In this case, northbound cyclists need to make a sharp left turn as they approach the Trafalgar underpass and we have previously mentioned how challenging that can be. Even though the steepest portion of the downslope is almost 300 metres away from that sharp left turn it still contributes to the elevated speeds as demonstrated by our coasting tests that were described in an earlier article. Even the Pottersburg Creek bridge, located just before Trafalgar Road contains a downslope of 5.8 % and this also contributes to the elevated speeds.
Above all, this is a research experiment. It is a safety lesson for those who need to consider how the characteristics of bike paths affect the public’s safety.