Skidology: Researchers explore ways to take some of the slip and slide out of winter
WinterLab, a new research facility in Canada, is studying how to prevent falls on all types of slippery surfaces. (Fotolia.com / January 30, 2013)
Thanks to WinterLab, a new research facility at the University of Toronto in Canada, we may soon have answers to pressing questions like these. WinterLab is the ultimate cold weather simulator, complete with icy surfaces, a snow-making machine and a mean wind fan. A particular focus is on the way we lose our grip in winter. Surfaces within the lab can be angled and the whole thing can be placed on a hydraulic base and tilted or jolted in any direction.
All the while, scientists can track someone inside slipping and sliding using a video motion-capture system, then analyze the data to see what's really going on. In other words, they make people fall over on camera -- all in the name of science!
It's a hot August day when I drop by to watch one of the lab's debut experiments: What happens when you put children on crutches onto ice? The participants are all kids with recent crutch experience, recruited through Toronto's Hospital for Sick Children. Sydney Savedra, 15, tells me she was jaywalking when she got hit by a car at the end of June and spent the next month with one foot off the ground. Now she's about to find out just how much worse the experience of being on crutches would have been in winter.
Opened in 2011, WinterLab looks like a pale blue ice cube sitting in an aircraft hangar. On the outside, it's decorated with dreamy paintings of ice floes and snow-dusted mountains. The sign on the door says, "No high heels on mesh floors, please."
Inside, there is indeed a mesh floor, but it's covered by a layer of ice. Above this are three walkways, side by side: one flat, cold and concrete; one flat and icy; and one sloped and icy. It's really cold in here, but apparently not cold enough: People keep opening the freezer door.
"A lot of tours came through yesterday," says Yue Li, who develops the lab's technology.
Today's experiment looks at whether adding small metal spikes at the base of crutches makes a person less likely to slip on icy surfaces. Sydney has to compare what it's like to walk on crutches along the three walkways with and without the ice grips. That may sound like a no-brainer, but slipperiness and the body's response to it is a preoccupation for some of science's brightest minds.
WATCH YOUR STEP
With her whole family looking on, Sydney dons winter clothing. The boot she'll wear on her "good" foot is weighed, photographed and has spherical motion-capture markers fixed to its surface. There are also markers on the crutches and on the fake cast that Sydney straps on her other foot. Every movement will be captured digitally for analysis.
Finally, Sydney buckles herself into a safety harness and enters the freezer. The rest of us watch on screens as she hobbles back and forth, the safety apparatus clanging and scraping after her like the chains of some medieval prisoner.
WinterLab is one of several units that make up the Challenging Environment Assessment Laboratory, or CEAL, a huge underground facility at the new $36-million Center for Rehabilitation Research. Other lab units are designed for studies on stairs, city streets and home-care devices.
When more testing conditions are required, these self-contained modules can be picked up and placed, Thunderbirds-style, on top of a huge hydraulic platform where they are jiggled about. In that scenario, there's even a high-tech bridge that folds down to give researchers access to the module. In time, the lab hopes to rent the units out.
WinterLab is also running a motorized scooter project, to work out which design can best handle ice and snow, in particular whether they can tackle slippery ramps without coming unstuck. A study on people who have become abnormally sensitive to cold after suffering hand injuries will soon be looking at what kinds of mitts and hand warmers best combat cold-induced pain.
Upstairs, in the Controlled Climate Performance Lab, a sort of older sister to WinterLab, there's a study underway on boot grips. Researchers want to know how ice cleats on the soles of shoes affect slipping and tripping. If this place had a soundtrack, it would be chattering teeth and the crunch of derrieres hitting snow.
Two weeks later, we reassemble for Sydney's final experiments. After each one, she fills out an assessment that asks about things like "tendency to slip."
"They should tell her to pull out her cell phone and text while she does this," her dad says. Now the whole story comes out: Not only was Sydney jaywalking when she was injured, but she was also texting. Watching her struggling on crutches, a month after discarding them for real, you can't help but feel she's doing her penance and then some.
The biomechanical analysis will identify every slip, even "microslips" that might not be visible from just watching. It will also measure the time taken to cross the walkway. Studied in combination with Sydney's post-test assessments, the whole experiment should give researchers a better idea of whether ice spikes cause fewer slips, help people move more quickly and make them feel more secure.
According to Lucas Murnaghan, the orthopaedic surgeon in charge of the project, this kind of empirical study is needed if doctors are to advise patients on which crutch tips best suit the conditions outdoors.
There is no jolting and shaking of WinterLab in the kids-on-crutches study but it's still painful to watch. Time and again on Sydney's ascent and descent, her crutches skid, sometimes leaving her supported by the harness. After an hour or so, she's finished. Her mother asks how it was.
"Slippery," Sydney mumbles.
(Alison Motluk is a science writer based in Toronto, Canada.)