Re: Turn FR into bike meter
On Friday 03 July 2009, arne anka wrote: > >> Hm, i was always under the impression that most bike systems use a > >> simple magnet and a reed switch (no need for hall effect sensor) for > >> both cadence and speed measurements. So any sensor from a regular > >> "bike computer" can be directly attached to the mic line of FR. > > > > They do, and they eventually fail > > how? The same as any other mechanical switch - operation becomes unreliable leading to inaccurate speed measurement, then fails completely. It doesn't happen quickly - it was on the second or third set of batteries so it would have been several years and thousands of miles. ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
>> Hm, i was always under the impression that most bike systems use a >> simple magnet and a reed switch (no need for hall effect sensor) for >> both cadence and speed measurements. So any sensor from a regular >> "bike computer" can be directly attached to the mic line of FR. > > They do, and they eventually fail how? ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
On Friday 03 July 2009, Paul Fertser wrote: > Cameron Frazier writes: > >> 1) I'm missing the cadence display = the number of revolutions of the > >> crank per minute; roughly speaking, this is the speed at which a > >> cyclist is pedalling/turning the pedals. > > > > For cadence detection, a hall effect sensor and a small magnet would > > cover it and have no moving parts/contacts ( see [1] for an > > example), > > Hm, i was always under the impression that most bike systems use a > simple magnet and a reed switch (no need for hall effect sensor) for > both cadence and speed measurements. So any sensor from a regular > "bike computer" can be directly attached to the mic line of FR. They do, and they eventually fail, hence the "no moving parts/contacts" bit. Both will work, but hall effect should last longer. ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
Cameron Frazier writes: >> 1) I'm missing the cadence display = the number of revolutions of the >> crank per minute; roughly speaking, this is the speed at which a >> cyclist is pedalling/turning the pedals. > > For cadence detection, a hall effect sensor and a small magnet would > cover it and have no moving parts/contacts ( see [1] for an > example), Hm, i was always under the impression that most bike systems use a simple magnet and a reed switch (no need for hall effect sensor) for both cadence and speed measurements. So any sensor from a regular "bike computer" can be directly attached to the mic line of FR. -- Be free, use free (http://www.gnu.org/philosophy/free-sw.html) software! mailto:fercer...@gmail.com ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
On Thu, Jul 02, 2009 at 06:34:00PM +0300, Risto H. Kurppa wrote: > I was thinking of using the audio jack or to be more specific, the > microphone line. Each revolution would connect the wires (with a > resistor maybe?) to create a pulse in the microphone line. This could > be recorded and analyzed with SW. It's okay to short the mic input to ground. With mic bias voltage enabled (an ALSA control somewhere) you should get key presses and releases reported in /dev/input/event*. -- Rask Ingemann Lambertsen Danish law requires addresses in e-mail to be logged and stored for a year ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
2009/7/2 Risto H. Kurppa > Hi! > > I bike and I have a Freerunner. > > Me too! :-) On Saturday I'm going on a 4 day bike trip. I plan to use Tango for navigation. I'll tell you how it went. I'm taking a paper map and a motorola too just in case :-) Michal ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
On Thursday 02 July 2009, Risto H. Kurppa wrote: > Hi! > > I bike and I have a Freerunner. > > GPS apps, like omgps are able to show & record the position, speed, > length of track etc. > > 1) I'm missing the cadence display = the number of revolutions of the > crank per minute; roughly speaking, this is the speed at which a > cyclist is pedalling/turning the pedals. > > -> any ideas how to build this, both hardware and software (=how to > convince some GPS software guy to implement it :) > > I was thinking of using the audio jack or to be more specific, the > microphone line. Each revolution would connect the wires (with a > resistor maybe?) to create a pulse in the microphone line. This could > be recorded and analyzed with SW. > > 2) Another thing missing is a tool to analyze my GPS track on-the-fly: > show the speed vs. time plot. > > Thanks for your ideas! Extra thanks if I'm able to have this up and > running in a week, planning to do a 170-200km bike trip in a day :) > > (more over, I think there could be a need for proper bike-oriented app > for Freerunner. Map display's nice but many other features might come > more important for people riding bike, like heart frequency, cadence, > current speed, avg, maybe also set target length and estimate the time > to reach it (I know Navit ~does this) etc.. - anyone interested?!) You could get a USB ANT receiver for ~$35 and write some code. It uses the FTDI usb-serial driver. There's example VB code for talking to Garmin heartrate monitors, and Garmin also have bike wheel and cadence sensors which you should be able to find on amazon if you search for "forerunner cadence" or similar. Suunto, VDO and others are doing bike and heart rate sensors using ANT too, and a few companies are also making power meters. The forum thread below contains linux c code for reading from Garmin, Suunto and other heartrate monitor belts. It's a bit old so there may have been some progress since then. http://www.sparkfun.com/commerce/product_info.php?products_id=8840 http://developer.garmin.com/forum/viewtopic.php?p=806&sid=75a21fca082b78b74e56dc3465ea2b03 ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
> Umh, you may take the freerunner attached to your leg and use accelerometers? Im thinking about using the neo freerunner while Im running/jogging. It could count my steps (using the accelerometer data), measure the exact distance, and plot the average speed across the distance. It could have many sexy statistics like calories, average "step distance", etc, etc. The ultimate feature would be of building some training course. Like the new could say, you are 1.3 sec behind of your average speed, helping with some music the jogging. It could warn if your step distance decrease. It could even help of developping your jogging skills. It could even measure the vertical distance (so how much do you jump while runnig), etc, etc. It looks like the same as attaching the neo to your leg while cycling. (while jogging, we have much more freedom where we want to wear the neo) So I was already toying with the idea. I hope somebody gets his hand dirty... Best regards, Laszlo ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
Risto H. Kurppa wrote: > > > 1) I'm missing the cadence display... > ...-> any ideas how to build this > planning to do a 170-200km bike trip in a day :) > Here are some ideas: as an extension of the above post: Place a Neodymium Magnet 1mm on the crank and as has been said a hall sensor fixed perhaps behind the bottom bracket cup with the wire routed along the inside of the frame, out via seatpost or headset cap or breathing hole, mount point, etc. Epoxy resin / cyanoacrylate might hold the magnet in place to avoid drilling, as it may not be a good idea to cause a weak spot in your cranks! You might want to check out how ABS works also, afaik basically a toothed wheel and hall sensor - which might mean the crank arm would cause a pulse. I'm not sure about this On a different tack, how about an optical sensor from a mouse / printer? This could be a good use of an otherwise redundant piece of computer waste. :) Though dirt may be a problem here. Also I can't see how to mount it easily. While your at how about some strain gauges and some glue http://en.wikipedia.org/wiki/Cycling_power_meter Best of luck on your cycle, are you using opencyclemap? Where are you cycling? -- View this message in context: http://n2.nabble.com/Turn-FR-into-bike-meter-tp3195758p3196474.html Sent from the Openmoko Community mailing list archive at Nabble.com. ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
On Thu, Jul 2, 2009 at 11:34 AM, Risto H. Kurppa wrote: > 1) I'm missing the cadence display = the number of revolutions of the > crank per minute; roughly speaking, this is the speed at which a > cyclist is pedalling/turning the pedals. For cadence detection, a hall effect sensor and a small magnet would cover it and have no moving parts/contacts ( see [1] for an example), you could do the same for wheels if you wanted to, though that would require some form of pre-processing to multiplex the signals I would think. [1] http://www.instructables.com/id/RGBike-POV-Open-project/ ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
speaking of this again. im still waiting for a car lap tracking app ala iphones lap timmer http://web.me.com/hschlangmann/LapTimer_Homepage/Snapshots/Seiten/Snapshots_LapTimer_%28iPhone%29.html On Thu, Jul 2, 2009 at 8:40 AM, Nicola Mfb wrote: > On Thu, Jul 2, 2009 at 5:34 PM, Risto H. Kurppa wrote: >> Hi! >> >> I bike and I have a Freerunner. >> >> GPS apps, like omgps are able to show & record the position, speed, >> length of track etc. >> >> 1) I'm missing the cadence display = the number of revolutions of the >> crank per minute; roughly speaking, this is the speed at which a >> cyclist is pedalling/turning the pedals. >> >> -> any ideas how to build this, both hardware and software (=how to >> convince some GPS software guy to implement it :) > > Umh, you may take the freerunner attached to your leg and use accelerometers? > >Nicola > > ___ > Openmoko community mailing list > community@lists.openmoko.org > http://lists.openmoko.org/mailman/listinfo/community > ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: Turn FR into bike meter
On Thu, Jul 2, 2009 at 5:34 PM, Risto H. Kurppa wrote: > Hi! > > I bike and I have a Freerunner. > > GPS apps, like omgps are able to show & record the position, speed, > length of track etc. > > 1) I'm missing the cadence display = the number of revolutions of the > crank per minute; roughly speaking, this is the speed at which a > cyclist is pedalling/turning the pedals. > > -> any ideas how to build this, both hardware and software (=how to > convince some GPS software guy to implement it :) Umh, you may take the freerunner attached to your leg and use accelerometers? Nicola ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Turn FR into bike meter
Hi! I bike and I have a Freerunner. GPS apps, like omgps are able to show & record the position, speed, length of track etc. 1) I'm missing the cadence display = the number of revolutions of the crank per minute; roughly speaking, this is the speed at which a cyclist is pedalling/turning the pedals. -> any ideas how to build this, both hardware and software (=how to convince some GPS software guy to implement it :) I was thinking of using the audio jack or to be more specific, the microphone line. Each revolution would connect the wires (with a resistor maybe?) to create a pulse in the microphone line. This could be recorded and analyzed with SW. 2) Another thing missing is a tool to analyze my GPS track on-the-fly: show the speed vs. time plot. Thanks for your ideas! Extra thanks if I'm able to have this up and running in a week, planning to do a 170-200km bike trip in a day :) (more over, I think there could be a need for proper bike-oriented app for Freerunner. Map display's nice but many other features might come more important for people riding bike, like heart frequency, cadence, current speed, avg, maybe also set target length and estimate the time to reach it (I know Navit ~does this) etc.. - anyone interested?!) r ps. http://www.obico.de/ -- | risto h. kurppa | risto at kurppa dot fi | http://risto.kurppa.fi ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community