Brake light with accelerometer
#1
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Joined: Sep 2008
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From: London
Bikes: Baum Romano, Brompton S2, Homemade Bamboo!
Brake light with accelerometer
https://www.bikerumor.com/2013/05/13/...ht/#more-60037
Looks like a much more practical and reliable solution to something that folks have been tinkering with for years.
Looks like a much more practical and reliable solution to something that folks have been tinkering with for years.
#3
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Joined: Sep 2005
Posts: 13,748
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From: Michigan
Bikes: Windsor Fens, Giant Seek 0 (2014, Alfine 8 + discs)
Seems a bit steep. Adding an accelerometer should only add maybe $8 to the cost of a brake light, and that's on one-off pricing, like if I just went to Digikey and bought a single accelerometer chip. It should interface fine to the processor that's already there in the light.
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Work: the 8 hours that separates bike rides.
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#4
Velodroom bike light
Well... as an engineer working on a similar, but less expensive and way better looking
bike light, I can tell it is not the components that cost. Electronics add maybe 4$ to this project.
Main expenses are probably R&D and marketing. Still, 100$ implies a bit too large contribution
from the backers to get their production costs down. After that they may reduce the price,
but not holding my breath for it. Just my biased opinion.
Project I'm working on: https://vd.ee
and a brief Velodroom trailer/teaser
bike light, I can tell it is not the components that cost. Electronics add maybe 4$ to this project.
Main expenses are probably R&D and marketing. Still, 100$ implies a bit too large contribution
from the backers to get their production costs down. After that they may reduce the price,
but not holding my breath for it. Just my biased opinion.
Project I'm working on: https://vd.ee
and a brief Velodroom trailer/teaser
#5
Thread Starter
Senior Member


Joined: Sep 2008
Posts: 2,423
Likes: 204
From: London
Bikes: Baum Romano, Brompton S2, Homemade Bamboo!
Well... as an engineer working on a similar, but less expensive and way better looking
bike light, I can tell it is not the components that cost. Electronics add maybe 4$ to this project.
Main expenses are probably R&D and marketing. Still, 100$ implies a bit too large contribution
from the backers to get their production costs down. After that they may reduce the price,
but not holding my breath for it. Just my biased opinion.
Project I'm working on: https://vd.ee
and a brief Velodroom trailer/teaser
bike light, I can tell it is not the components that cost. Electronics add maybe 4$ to this project.
Main expenses are probably R&D and marketing. Still, 100$ implies a bit too large contribution
from the backers to get their production costs down. After that they may reduce the price,
but not holding my breath for it. Just my biased opinion.
Project I'm working on: https://vd.ee
and a brief Velodroom trailer/teaser
Much better looking and more practical (mount etc)..
#6
Velodroom now also covered in bikerumor: https://www.bikerumor.com/2013/05/14/...ve-bike-light/
We are also working on front light and want to make it the best one in the world,
so any feedback-suggestions-comments are welcome.
We are also working on front light and want to make it the best one in the world,
so any feedback-suggestions-comments are welcome.
Last edited by Indrek Rebane; 05-14-13 at 05:24 PM.
#7
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Joined: Jun 2007
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From: Walyalup, Australia
Bikes: Surly Long Haul Trucker, Salsa Mukluk, Riese & Muller Supercharger GT Rohloff (Forthcoming)
Interesting and thanks for sharing. I have thought of fitting a Busch & Mueller BrakeTec as I run a dynamo on one of my bikes.
Andrew
Andrew
#8
Interesting and thanks for sharing. I have thought of fitting a Busch & Mueller BrakeTec as I run a dynamo on one of my bikes.
Good engineering and ingenious operating principle. Also very reasonably priced.
Velodroom is working on dynamo model as well, but this will not be on the market before 2014.
Dynamo connection is currently mandatory for bike lights in Germany by StVZO TA. Of course
we will do our best to make better light than B&M. However, if you need one now there is no
match to B&M as far as I know. And this comes from their competitor.
#9
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Joined: Dec 2010
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From: northern Deep South
Bikes: Fuji Touring, Novara Randonee
AIUI B&M uses a frequency comparator to detect when the bike is slowing (from the dyno hub). That seems likely to be cheaper (all electronic) than adding an accelerometer into the mix.
#10
Accelerometers (and gyros), as used in cell phones for example, are inexpensive solid state electronic devices.
#11
#12
Senior Member
Joined: Sep 2011
Posts: 220
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From: north providence, r.i.
Bikes: Nashbar trekking bike
I came across these https://www.ebay.com/itm/111058289337...84.m1497.l2649.
can't beat the price. I order 2 of these to use on my bike rack to improve the brake light visibility. sinc my bike blocks my brake lights.
can't beat the price. I order 2 of these to use on my bike rack to improve the brake light visibility. sinc my bike blocks my brake lights.
#13
Banned
Joined: Jun 2010
Posts: 43,586
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From: NW,Oregon Coast
Bikes: 8
As the hub dynamo has Power pulses, the B&M one lights brighter as the Pulse Frequency drops .
in normal operation there is a capacitor to smooth out the pulses
Flashing tail lights are verboten in German bike regulations.
but Asian Export Stuff sells withall those flashing Modes.
in normal operation there is a capacitor to smooth out the pulses
Flashing tail lights are verboten in German bike regulations.
but Asian Export Stuff sells withall those flashing Modes.
#14
Seems a bit steep. Adding an accelerometer should only add maybe $8 to the cost of a brake light, and that's on one-off pricing, like if I just went to Digikey and bought a single accelerometer chip. It should interface fine to the processor that's already there in the light.
#15
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Joined: Sep 2005
Posts: 13,748
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From: Michigan
Bikes: Windsor Fens, Giant Seek 0 (2014, Alfine 8 + discs)
OK, so add about 80 cents minus whatever the custom silicon costs, to the total cost. 80 cents is what I can buy small processors for in relatively small quantities (100+) In 5000 quantities, it's down to about 60 cents or less. The accelerometer is a more significant cost, they're usually a couple of bucks in the quantity I buy, but I'm sure when you start buying a few thousand the price drops considerably.
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Work: the 8 hours that separates bike rides.
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#16
I'm glad to announce that things have moved a notch closer with Velodroom bike light.
Today we are launching our Kickstarter campaign and hopefully reach our set goal.
Kickstarter page:
https://www.kickstarter.com/projects/velodroom/velodrooms-smart-bicycle-light
Today we are launching our Kickstarter campaign and hopefully reach our set goal.
Kickstarter page:
https://www.kickstarter.com/projects/velodroom/velodrooms-smart-bicycle-light
#17
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Joined: Mar 2019
Posts: 396
Likes: 15
Anyone experienced taillight getting brighter upon acceleration as well? Seems like accelerometer is working both ways on some lights. Couldn't find anything about such a specific issue so had no other choice but to ask here.
#18
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Joined: Aug 2010
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From: Madison, WI
Bikes: 1961 Ideor, 1966 Perfekt 3 Speed AB Hub, 1994 Bridgestone MB-6, 2006 Airnimal Joey, 2009 Thorn Sherpa, 2013 Thorn Nomad MkII, 2015 VO Pass Hunter, 2017 Lynskey Backroad, 2017 Raleigh Gran Prix, 1980s Bianchi Mixte on a trainer. Others are now gone.
Eight year old thread.
#19
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Joined: Aug 2008
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From: Ann Arbor, MI
Bikes: 15 Kinesis Racelight 4S, 76 Motebecane Gran Jubilée, 17 Dedacciai Gladiatore2, 12 Breezer Venturi, 09 Dahon Mariner, 12 Mercier Nano, 95 DeKerf Team SL, 19 Tern Rally, 21 Breezer Doppler Cafe+, 19 T-Lab X3, 91 Serotta CII, 23 3T Strada
Yeah, is this a zombie resurrection for an imagined issue?! Haha!
#20
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From: Altadena, CA
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As far as I've been able to tell, it only gets brighter under deceleration. That said, I have a hard time riding and seeing my tail light at the same time. I'm just not that flexible.
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RIP 01/08/25...2022 Trek Supercaliber, 2018 Storck Fascenario.3 Platinum, 2018 Trek Procaliber SL Singlespeed, 2017 Bear BR1, 2003 Time VX Special Pro, 2001 Colnago VIP, 1999 Trek 9900 singlespeed, 1977 Nishiki ONP
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