Gyrfalcon

Hello,

I am an Engineering Design and Development student working on a project to improve nighttime bicycle safety. My team has researched the problem, and we believe we are able to understand it, however, as veteran cyclists, you have first hand experience with the issue. Would any of you be willing to lend us your expertise to review our findings? We know that your time is valuable and limited, so we appreciate any advice you can offer.

If you have a few minutes to give us some comments on our summary of the problem, I have attached it to this post.

Thank you,
Evan Novak

cranky old road 

"The time of day that most bicycle fatalities occurred was between the hours of 6:00 and 9:00"

You might specify AM and/or PM

Artkansas 

True, in December it will be dark at both 6 AM and 6 PM.

I'm sorry this survey is done via a PDF. Coming from an unknown source, I'm less likely to trust it than if it were at Survey Monkey or some other bug-free source.

Maybe Mr/Ms Novak will resubmit it in a more trustworthy form and tighter questions.

Gyrfalcon

I apologize if the PDF format raises security concerns, I would be happy to submit it in another way if that alleviates the security risk. However, it is not really a survey, but a summary of the findings of my team about nighttime bicycle safety. This subforum seemed like the best place to ask for feedback on these findings and ask additional questions about the issue. If this isn't the right place, could you direct me to a more appropriate subforum?

Also in reference to the 6 to 9 figure, it is PM and I will amend it as such.

RPK79

As an employed cyclist most of my weekday cycling is done between the hours of 6 and 9 PM since that is after I get off of work. It is also during daylight (in the summer which is when most of my cycling occurs). If my personal experience is similar to others then it only makes sense that most cycling fatalities are between those hours and that your initial premise is wrong (that being that nighttime is the cause of these accidents).

Gyrfalcon

This is a valid concern, however some of the other data we found refutes that idea. In figure 3.1 from the 2012 National Survey of Bicyclist and Pedestrian Attitudes and Behavior, it tells us that over 70% of cyclists asked reported almost no or no dark or near dark cycling. Only 16% of respondents said they did half or more of their cycling in the dark or near dark. This seems to point to nighttime cycling being at least somewhat more dangerous than the daytime, in addition to the number of patents and products we found for bicycle safety that were lighting or other visibility device. I can post the patent and product search information if you like.

Thank you for your input.

RPK79

I imagine many of those fatalities involve intoxicated cyclists riding with zero lighting or safety equipment.

wphamilton

I have commuted by bike almost every day, year round for the past 5 years (95% in aggregate) and about 60% of the days for 3 years prior to that.

My greatest concern is early evening hours, the 6-9 for example, in the relatively rare condition when the sun is low and in line with myself and drivers. It's not dark yet. At low angles the sunlight can distract or completely obscure vision, and lights such as in the included patent won't do a thing to help it. Lights would need to be extremely bright, and probably flashing. Seriously, you might also look into the relative visibility of different wavelengths in those conditions only (I don't think that's been done specifically for low sun angles, especially in front of the driver)

In the dark of night on the other hand, even dim lights are sufficient to be visible.

Gyrfalcon

That is interesting. So the main problem is not the amount of light in those evening hours, but its position relative to the cyclist, which then makes it difficult for motorists to see the cyclist? A brief search says that light that is green or orange might be most visible in those conditions, however as you mention it might be different for the extremely bright conditions caused by the direct light of the sun.

One of the commercial products we examined, the Zackees turn signal gloves, used an ambient light sensor to allow the lighting to be brighter to overcome ambient light during the day, and dim at night to provide visibility without straining the battery. Perhaps a feature like this would be helpful in solving this particular issue?

Thank you for your input.