visibility of DRL

Tosspot wrote:
On 05/04/2019 15.41, Sepp Ruf wrote:
Tosspot wrote:
On 05/04/2019 00.17, wrote:

In general flashlights are bad because there can be a *lot* of bleed
outside the designed boresight angle. I suffer from this a lot from
people coming the other way at night, but tbf, it is very variable, with
some flashlights having little bleed. How do I tell? The conical beam
shape is a dead giveaway. With respect to your test, not a bad idea.
My IQ-X doesn't even illuminate tail lights/reflectors, and still throws
a beam some 20ft down the road, and in an exact mirror of your test, I

20ft - are you so greatly enjoying seeing all of the beam? I'd suggest you
set it to at least 20 yards if you ride more than half as fast as Jay or Joerg.

fitted a flashlight to the handlebars to try and determine the angle at
which the same occurred. It required *my* light to be set far to far
down to be useful.

Steady 20kph (say 15mph), it isn't pitch dark but that's easily enough
to avoid pot holes, broken bottles etc. It might be a bit more, but I'd
say no more than 30. You got me thinking now, I'll have to dream up a
way of measuring it. I was guessing at lengths of 6ft of me.


That does sound rather low, barely braking distance even at the upper end,
I have the royal parks which are empty bar Deers, was able to experiment
few years back, the admittedly powerful though wide rather than long beam
on the MTB light and the much less powerful Exposure Strada with its
flatter but less wide beam both light up the road at full chat 100ft or so.

20/30ft I can believe from some of the low powered blinkies and Dynamos you
do see now and then, but not a fairly expensive light.

Roger Merriman

On 4/6/2019 7:21 PM, Roger Merriman wrote:

I see fairly regularly, folks with the light angled up, now I’m not sure if
this choice or slipped?

The great majority of bike headlights are designed to be clamped to the
handlebars. To me, this indicates how much bikes are considered toys
instead of vehicles.

First, in the best of circumstances, one can't guarantee the light will
be aimed properly up and down (i.e. its pitch is badly controlled). And
some straps or clamps can slip pretty easily. Some handlebars have a
diameter outside the range of a strap or clamp. Some handlebars are
curved in such a way that it's difficult to get the headlight aimed
properly in the other two directions (yaw and roll). And most of those
lights are useless if the cyclist chooses to use a handlebar bag, or to
carry large packages in a front basket.

ISTR reading that British bikes (at least, non-racing ones?) once were
required to have standard headlamp mounts attached to their front forks.
The idea was, supposedly, that one could easily fit a standard headlight
to any bike. Does anyone have any knowledge of that?

--
- Frank Krygowski

On 4/7/2019 12:07 AM, Jeff Liebermann wrote:
On Sun, 07 Apr 2019 10:31:41 +0700, wrote:

You need to do some more research.

I need to go back to working on my income taxes.

Reelight, the maker of the little magnet powered lights that were used
in the study, seems to have provided the lights used in the study
free. Now THINK! Someone just gave you almost 2,000 lights so that you
can make your study...

Yep. The way it works is the researchers own the content of the
paper, while the driving force behind the project owns the conclusion.
Since most readers will never read beyond the initial summary, this is
sufficient. I've read research papers where the conclusions have
little or no connection to the data in the body of the report.

However, we have a new contender in the bicycle safety study business.
Flashing headlights are out, and bright yellow jackets are in:
https://ars.els-cdn.com/content/image/1-s2.0-S0925753517313528-gr1_lrg.jpg
"The effect of a yellow bicycle jacket on cyclist accidents"
https://www.sciencedirect.com/science/article/pii/S0925753517313528
The accident rate (AR) (accidents per person month) for
personal injury accidents (PIAs) for the test group was
47% lower than that of the control group. For accidents
involving cyclists and motor vehicles, it was 55% lower.
I wonder if Denmark will also make wearing bright yellow bicycle
jackets manditory, just like the daylight running lights? Note that
both studies seem to have been performed at Aalborg University,
Denmark.

AFAIK, daytime running lights are not mandatory anywhere. Please let me
know if I'm wrong.

Regarding yellow jackets: France instituted a law in 2008, I believe,
that requires wearing a specific type of hi-viz safety vest when cycling
at night in the countryside. Supposedly it's poorly enforced (as usual
with such nonsensical laws).

We were in France for three weeks in 2012, cycling and traveling by car
and train. I don't recall ever seeing one of those vests. We certainly
didn't carry them.


--
- Frank Krygowski

On 4/6/2019 8:52 PM, Jeff Liebermann wrote:
On Sat, 6 Apr 2019 23:21:59 -0000 (UTC), Roger Merriman
wrote:

I see fairly regularly, folks with the light angled up, now I’m not sure if
this choice or slipped? My personal bug bear is folks in the Royal Parks
that are large and unlit so dark who have there lights on flash, the
temptation to return with interest the favour and boot the light to full is
high, I don’t but it gives me a warm glow just thinking about it!
Roger Merriman

Well, if you change your mind and decide to do something about the
flasher in the face problem, I suggest you look into weaponizing your
bicycle headlight.

"The Incapacitating Flashlight. An LED flashlight makes culprits
vomit"
https://www.technologyreview.com/s/408360/the-incapacitating-flashlight/

"LED Incapacitator"
https://en.wikipedia.org/wiki/LED_Incapacitator
http://www.intopsys.com/technologies/featured-technologies/led-incapacitator-2/

"Flicker vertigo"
https://en.wikipedia.org/wiki/Flicker_vertigo

"Incapacitating flashing light apparatus and method"
https://patents.google.com/patent/US7180426B2/
https://patentimages.storage.googleapis.com/c6/43/13/d9e822141911a8/US7180426.pdf

"Can Strobe Weapons Really Make You Puke"?
https://www.wired.com/2008/05/strobe-weapons-2/
"I don’t think we've had anyone actually be sick",
says Bob Lieberman, CEO of Intelligent Optics, which
makes the LED Incapacitator.
Oh well. I was hoping it would make the view vomit.



It's a start.
What cyclists need is a handheld death ray for texting drivers.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971

On Sun, 7 Apr 2019 11:08:12 -0400, Frank Krygowski
wrote:

On 4/7/2019 12:07 AM, Jeff Liebermann wrote:
On Sun, 07 Apr 2019 10:31:41 +0700, wrote:

You need to do some more research.

I need to go back to working on my income taxes.

Reelight, the maker of the little magnet powered lights that were used
in the study, seems to have provided the lights used in the study
free. Now THINK! Someone just gave you almost 2,000 lights so that you
can make your study...

Yep. The way it works is the researchers own the content of the
paper, while the driving force behind the project owns the conclusion.
Since most readers will never read beyond the initial summary, this is
sufficient. I've read research papers where the conclusions have
little or no connection to the data in the body of the report.

However, we have a new contender in the bicycle safety study business.
Flashing headlights are out, and bright yellow jackets are in:
https://ars.els-cdn.com/content/image/1-s2.0-S0925753517313528-gr1_lrg.jpg
"The effect of a yellow bicycle jacket on cyclist accidents"
https://www.sciencedirect.com/science/article/pii/S0925753517313528
The accident rate (AR) (accidents per person month) for
personal injury accidents (PIAs) for the test group was
47% lower than that of the control group. For accidents
involving cyclists and motor vehicles, it was 55% lower.
I wonder if Denmark will also make wearing bright yellow bicycle
jackets manditory, just like the daylight running lights? Note that
both studies seem to have been performed at Aalborg University,
Denmark.

AFAIK, daytime running lights are not mandatory anywhere. Please let me
know if I'm wrong.

Sorry, I though they were mandatory in Denmark. They are mandatory
for cars, motorcycles, and mopeds, but not (yet) for bicycles:

http://vbn.aau.dk/files/274548813/Safety_effects_of_permanent_running_lights_for_bic ycles.pdf

In 2004 the Danish Cyclists Federation conducted a national
registration of cyclists without cycling lights within lightning
hours. According to the registration 29% of all the recorded
cyclists did not use a cycling light although it is mandatory
within the lightning hours. In 2009 the proportion of cyclists
without cycling lights had fallen to 16%. According to both the
Danish Cyclists Federation and Danish Police this is due to the
availability and subsequent widespread although not mandatory
use of the bicycle running lights (Fausbøll, 2010).

Danish Cycling Rules
https://www.donkey.bike/denmark-cycling-rules/
You are required to carry lights at all times during
the day, even if you’re not using them.

DAYTIME RUNNING LIGHTS IN DENMARK
https://trid.trb.org/view/464494

Regarding yellow jackets: France instituted a law in 2008, I believe,
that requires wearing a specific type of hi-viz safety vest when cycling
at night in the countryside. Supposedly it's poorly enforced (as usual
with such nonsensical laws).

We were in France for three weeks in 2012, cycling and traveling by car
and train. I don't recall ever seeing one of those vests. We certainly
didn't carry them.

Looks like it became mandatory in 2016 for motorcycles and scooters,
but no mention of bicycles:
High-visibility Vests Become Mandatory for Riders in France
https://www.autoevolution.com/news/high-visibility-vests-become-mandatory-for-riders-in-france-95662.html

Probably better to ask someone living in Europe for the exact
situation on daytime running lights and bicycle dress code.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sun, 07 Apr 2019 11:31:01 -0500, AMuzi wrote:

On 4/6/2019 8:52 PM, Jeff Liebermann wrote:
On Sat, 6 Apr 2019 23:21:59 -0000 (UTC), Roger Merriman
wrote:

I see fairly regularly, folks with the light angled up, now I’m not sure if
this choice or slipped? My personal bug bear is folks in the Royal Parks
that are large and unlit so dark who have there lights on flash, the
temptation to return with interest the favour and boot the light to full is
high, I don’t but it gives me a warm glow just thinking about it!
Roger Merriman

Well, if you change your mind and decide to do something about the
flasher in the face problem, I suggest you look into weaponizing your
bicycle headlight.

"The Incapacitating Flashlight. An LED flashlight makes culprits
vomit"
https://www.technologyreview.com/s/408360/the-incapacitating-flashlight/

"LED Incapacitator"
https://en.wikipedia.org/wiki/LED_Incapacitator
http://www.intopsys.com/technologies/featured-technologies/led-incapacitator-2/

"Flicker vertigo"
https://en.wikipedia.org/wiki/Flicker_vertigo

"Incapacitating flashing light apparatus and method"
https://patents.google.com/patent/US7180426B2/
https://patentimages.storage.googleapis.com/c6/43/13/d9e822141911a8/US7180426.pdf

"Can Strobe Weapons Really Make You Puke"?
https://www.wired.com/2008/05/strobe-weapons-2/
"I don’t think we've had anyone actually be sick",
says Bob Lieberman, CEO of Intelligent Optics, which
makes the LED Incapacitator.
Oh well. I was hoping it would make the view vomit.

It's a start.
What cyclists need is a handheld death ray for texting drivers.

It might be possible to design an EMP (electromagnetic pulse) weapon
that can be mounted on a bicycle. The EMP device should be
directional so that only the smart phone is destroyed, and not the
electronics in any nearby automobiles. If that's impossible, it might
be possible to design an EMP device that could be launched from a
bicycle, attach itself to the automobile, and then disable all the
attached electronics. The electronics for such a device is easy
enough, but launching the power source (battery?) along with the
electronics might be a bit much. I suppose a drone delivered Tesla
coil would produce a satisfactory lightning bolt sufficient to destroy
the smart phone and optionally get the attention of the driver (if
they survive). If none of the aformentioned are acceptable, a simple
cellular jammer should disrupt communications long enough for the
driver to find a different distraction. However, if you insist on
using lethal force to discourage texting, there are a variety of more
conventional weapon mounts available for bicycle mounting:
https://www.google.com/search?tbm=isch&q=bicycle+mounted+weapons






--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sun, 7 Apr 2019 10:54:15 -0400, Frank Krygowski
wrote:

On 4/6/2019 7:21 PM, Roger Merriman wrote:

I see fairly regularly, folks with the light angled up, now I’m not sure if
this choice or slipped?

The great majority of bike headlights are designed to be clamped to the
handlebars. To me, this indicates how much bikes are considered toys
instead of vehicles.

But they didn't use to be. And in foreign countries where wheel driven
generators were normally fitted to "transportation" bikes they still
are today.

I definitely remember Schwin bikes, the good strong ones with the
double top tubes, that had a front light mount mounted under the head
bearing lock nut.

But then them foreign "English 10 speed racing bikes" got popular and
fixed lights disappeared. Too heavy for a "racing" bike I guess :-)
--
cheers,

John B.

On Sun, 7 Apr 2019 11:08:12 -0400, Frank Krygowski
wrote:

On 4/7/2019 12:07 AM, Jeff Liebermann wrote:
On Sun, 07 Apr 2019 10:31:41 +0700, wrote:

You need to do some more research.

I need to go back to working on my income taxes.

Reelight, the maker of the little magnet powered lights that were used
in the study, seems to have provided the lights used in the study
free. Now THINK! Someone just gave you almost 2,000 lights so that you
can make your study...

Yep. The way it works is the researchers own the content of the
paper, while the driving force behind the project owns the conclusion.
Since most readers will never read beyond the initial summary, this is
sufficient. I've read research papers where the conclusions have
little or no connection to the data in the body of the report.

However, we have a new contender in the bicycle safety study business.
Flashing headlights are out, and bright yellow jackets are in:
https://ars.els-cdn.com/content/image/1-s2.0-S0925753517313528-gr1_lrg.jpg
"The effect of a yellow bicycle jacket on cyclist accidents"
https://www.sciencedirect.com/science/article/pii/S0925753517313528
The accident rate (AR) (accidents per person month) for
personal injury accidents (PIAs) for the test group was
47% lower than that of the control group. For accidents
involving cyclists and motor vehicles, it was 55% lower.
I wonder if Denmark will also make wearing bright yellow bicycle
jackets manditory, just like the daylight running lights? Note that
both studies seem to have been performed at Aalborg University,
Denmark.

AFAIK, daytime running lights are not mandatory anywhere. Please let me
know if I'm wrong.

The results of the Odense was used to justify the Danish Highway
Department modifying the bicycle light code to ALLOW the use of
daylight running lights.

Regarding yellow jackets: France instituted a law in 2008, I believe,
that requires wearing a specific type of hi-viz safety vest when cycling
at night in the countryside. Supposedly it's poorly enforced (as usual
with such nonsensical laws).

We were in France for three weeks in 2012, cycling and traveling by car
and train. I don't recall ever seeing one of those vests. We certainly
didn't carry them.

Well, there you go, being ultra brave you deliberately endangered
yourselves, just like the helmet less mountain climber :-(
--
cheers,

John B.

On 4/6/2019 3:49 PM, wrote:
On Sat, 6 Apr 2019 07:27:25 -0700, sms
wrote:

On 4/6/2019 4:22 AM, Roger Merriman wrote:

I was getting the occasional car pulling out when I just had a fairly
normal cheap light (day time) which clearly folks just hadn’t
noticed/looked, for other reasons I bought a nice front light, so I don’t
have to run two since it has a remote so can easily go from full to dip or
close enough.

But I have noticed that running it on low/dip during the day seems to have
stopped folks absent minded pulling out.

I do cross some fairly major roads so something to cut though is handy and
is zero cost essentially I also have some rear lights though blinding folks
is less of a issue with rear lights.

Exactly. The biggest change in driver behavior I've seen when using
adequate lights, both day and night, is a reduction in vehicles exiting
parking lots in front of me, or making right on red turns in front of
me. And as most of us that drive have also experienced, the "I just
didn't see you" excuse that vehicle drivers use, actually does have some
validity--you are MUCH more visible when you use an adequate light, both
day and night.

Since multiple studies have come to this conclusion regarding DRLs it
should not surprise anyone (well unless they abhor statistically
significant studies and research, and judging from the number of
climate-change deniers there are still some of these individuals around).

Yes the often mentioned Odense study (of some 1,845 users and some
2,000 non users over a 12 month period) showed permanent running
lights reduced accidents by 19%.

That was only one study of the effectiveness of DRLs. But yes, it showed
a significant advantage.

On Sun, 7 Apr 2019 16:24:57 -0700, sms
wrote:

On 4/6/2019 3:49 PM, wrote:
On Sat, 6 Apr 2019 07:27:25 -0700, sms
wrote:

On 4/6/2019 4:22 AM, Roger Merriman wrote:

I was getting the occasional car pulling out when I just had a fairly
normal cheap light (day time) which clearly folks just hadn’t
noticed/looked, for other reasons I bought a nice front light, so I don’t
have to run two since it has a remote so can easily go from full to dip or
close enough.

But I have noticed that running it on low/dip during the day seems to have
stopped folks absent minded pulling out.

I do cross some fairly major roads so something to cut though is handy and
is zero cost essentially I also have some rear lights though blinding folks
is less of a issue with rear lights.

Exactly. The biggest change in driver behavior I've seen when using
adequate lights, both day and night, is a reduction in vehicles exiting
parking lots in front of me, or making right on red turns in front of
me. And as most of us that drive have also experienced, the "I just
didn't see you" excuse that vehicle drivers use, actually does have some
validity--you are MUCH more visible when you use an adequate light, both
day and night.

Since multiple studies have come to this conclusion regarding DRLs it
should not surprise anyone (well unless they abhor statistically
significant studies and research, and judging from the number of
climate-change deniers there are still some of these individuals around).

Yes the often mentioned Odense study (of some 1,845 users and some
2,000 non users over a 12 month period) showed permanent running
lights reduced accidents by 19%.

That was only one study of the effectiveness of DRLs. But yes, it showed
a significant advantage.

I find it strange. You keep making statements, such as "multiple
studies" but for some reason you always neglect to provide any
references to actual studies.

But than, that is the politician's method of "proving" something,
isn't it. Just stand tall, chin up, and speak in a loud authoritative
voice and keep repeating the same thing over and over. Perhaps someone
will believes it.
..
--
cheers,

John B.