Lap timing

[Jingers]

I have a delimma.

Two products available to me.

One uses a optic beam sensor to track laptimes.

One is a gps unit.

Provided the price is similar which one would be better? Keep in mind the GPS unit is also able to set sector times easily too. I am worried the GPS might be marred by bad weather?

[fueltank]

Unless you use GPS systems like surveyors use. Which cost like 20k. They are accurate to a few metres.
I'd go the beam.

Some beams you can do sectors with additional devices placed around the track.


Unless of course you're talking about using the GPS units F1 teams use.

[Jingers]

but yeah pain in the ass u r not excatly going to go around the whole track and put tripod there LOL.

Just worried if one single overhead cloud will hinder performance

[00dc2]

gps tracking isn't accurate to a few meters in the way most people imagine.

the location drifts a fair bit from hour to hour.. but only drifts a little from minute to minute.

this is important because it doesnt matter that every lap starts/finishes at the same spot. its important that each lap finishes close to where IT started.

so if the location drifts 10 or 20m during the day its no big deal cos the location probably only drifted 2-3m during the time it took you to do a lap.

at 150km/hr your doing 41m/sec so the 3m error is only 0.07sec

this is one guys GPS base dlap timer. here at the bottom of the page he talks about the accuracy thing i have mentioned above.
http://www.schlangmann.mynetcologne.de/HarrysLapTimer/

I am currently writing my own GPS lap timing system using this GPS receiver:
http://www.u-blox.com/products/aek_4p.html

This is a 4Hz GPS receiver.

The Driftbox uses 10Hz apparently.. http://www.driftbox.com/drift.html but its like $1k apparently..

Clouds wont be a problem.. trees and buildings around the track are a problem.

szymonsta uses the http://www.aimsports.com/products/tg/index.html
i think... he was pretty happy with it. but yeah.. no splits and you cant examine your data later on a pc... which is what i want to do with my system.. as well as use it to measure 0-400m and 0-100 times...

[TeMp]

Yeah, get the same one as szymonsta Jing!

That means you can join in our GB!

[Noel]

GPS doesn't really get affected by weather once it initializes correctly. Since it requires a minimum of 4 GPS to lock on to the device (StarRF III - Current GPS module grade/spec scans 16 GPS simutaneously and locks up to 4~8 GPS) to get a reading. It either locks ON or OFF. If you get a lock on, you'd get a fair reading. If it doesn't not lock on, then you won't even get a reading.

[szymonsta]

driftbox or other gps systems have advantage of being able to use outside of lap timing, eg. 0-100km/h, 0-400m tests. but price is close to $1k. im not sure about the accuracy of lap gps type lap-timers, but i know that club level motorsport and many semi-professional or professional race series are timed with optic beam as it is a known accuracy. (and cheaper than driftbox type thing).
i have to say i am very happy with my aimsports mychron TG timer, and knowing your lap time each lap is invaluable!

[TAFKA TMB]

I’ve got a “beam” lap timer and while it is good, I’d rather have a GPS system that can break a lap down in to sectors. That way I could get a best “possible” lap time (adding the best times for 4 sectors or whatever).

Nothing like chasing down another car where you are both pushing and your in-car display shows your lap times getting personal best after personal best. The inverse situation is when you think that you are driving the wheels off and the lap timer shows you 3 secs slower than your previous best (or where you want to be). At least it is real time and you don’t have to wait for results to be printed, pinned up, etc.

[fueltank]

Bringing this from the dead...
http://www.racechrono.com/?lang=en

[00dc2]

Bringing this from the dead...
http://www.racechrono.com/?lang=en

yeah i have switched to using this software on my nokia N95 with a 5Hz GPS unit. Accuracy is better than 0.1sec. does sectors and its great cos it shows your speed at all points on the track and lets you compare laps against each other. Better than just knowing what your lap time was... imo. i will post some screen shots from my phone once i get taking screen shots working... :/

[TAFKA TMB]

yeah i have switched to using this software on my nokia N95 with a 5Hz GPS unit. Accuracy is better than 0.1sec. does sectors and its great cos it shows your speed at all points on the track and lets you compare laps against each other. Better than just knowing what your lap time was... imo. i will post some screen shots from my phone once i get taking screen shots working... :/

Can this be made to work with a Nokia N73?

[Jingers]

Should be fine

RaceChrono version 0.41 for Nokia Series 60 Third Edition.
Supported phones: Nokia 3250, 5500 Sport, E50, E51, E60, E61, E61i, E62, E65, E70, E90, N71, N73, N75, N76, N77, N80, N81, N91, N92, N93, N93i, N95, 5700 XPressMusic, 6110 Navigator, 6120 Classic, 6120, 6121, 6290, Samsung SGH-i400, SGH-i450, SGH-i520, SGH-i550, SGH-i560, LG KS10.

[noodleman]

somebody please create wakie track and send it to me

[TAFKA TMB]

somebody please create wakie track and send it to me

already there according to this site:
http://www.racechrono.com/forum/comm...iscussionID=19


So what sort of GPS do I need, the Nokia standard one? Sorry for the noob questions, I'm a beginner at this kind of stuff.

[00dc2]

you need an external Bluetooth GPS.

I bought a 5Hz one to get more accurate timing than 1Hz.

this is the guy on ebay.
http://stores.ebay.com/Blipgear

He has a few GPS's that he's selling.. only one listing is for the special order 5Hz ones.. Dont fark it up and choose one that isnt 5Hz. The regular 1Hz ones are capable of doing 5Hz but this has to be set at the factory. The 5Hz one is US $99.97.

does this link work?
http://cgi.ebay.com/NEW-Solar-Blueto...QQcmdZViewItem