Low cost lap-timer...interested?

[Marmoot]

(correct me if I'm wrong. it's been 7 years since I read Comms books)

Yagi is a T antennae/aerial that will transmit signal perpendicular to the antenna (hence it is relatively directional).

[skelstar]

(correct me if I'm wrong. it's been 7 years since I read Comms books)

Yagi is a T antennae/aerial that will transmit signal perpendicular to the antenna (hence it is relatively directional).

So did I inadvertantly draw a signal transmitted from a yagi style aerial?
I was just thinking of sticking the txtr in a metal tube. I have to talk to a workmate who is a radio engineer.

[brad]

Hey guys,

Im not a racer but I AM an Electronics Engineer.

I kinda had the idea of building a very low cost/budget lap timer. What Im thinking is purely having a box with a simple display on your handlebars and a trigger located very near one of your handgrips. The idea (havent fully thought it through yet) is that you would pull the trigger as you go through the start/finish or a fixed point on the circuit. The display would tell you the elasped time since you last 'pulled the trigger'.

Questions:

Would anyone be interested in buying one? (very low cost, not looking to retire on this product).

Is there something that already does this?

Is it too simple, difficult to use? Remembering that it could be any fixed point on the circuit. You could even do the timing through a section of the course.

Thinking about hiring them out at trackdays/races too maybe...


What do people think? Enough interest may warrant further investigation.

keen as to try or even test for ya,your original idea to keep it cheap and small is good let us no when you've got one working off the handle bars with a trigger sounds good

[SimJen]

You could have two transmitters 1/4 mile apart for timing

Or to make it real easy, use a big piece of string with an electric clock on the bike. The string has to be the exact length of the perfect race line of a single lap of the track.
Attach the string to the start line with a large stake and ride off on your perfect lap.
The string pulls the battery out when you have done exactly one lap.
I forsee some minor teething troubles with my solution but nothing a complete redesign won't iron out.

[skelstar]

Talked to my radio engineer mate at work and he reckons a FM transmitter is a bad idea. Reckons lasers, or a high-intensity LED (Luxeon Star $30) on the side of the track, and a photo-diode on the bike (pointing left) with a band-pass optical filter. Pulse train the LED signal so you can try and eliminate the ambient light.

Fuck it...might just do the trigger idea .

[cowpoos]

Talked to my radio engineer mate at work and he reckons a FM transmitter is a bad idea. Reckons lasers, or a high-intensity LED (Luxeon Star $30) on the side of the track, and a photo-diode on the bike (pointing left) with a band-pass optical filter. Pulse train the LED signal so you can try and eliminate the ambient light.

Fuck it...might just do the trigger idea .

what sort of transmitter do they use on clothing store tags?

[Bert]

Talked to my radio engineer mate at work and he reckons a FM transmitter is a bad idea. Reckons lasers, or a high-intensity LED (Luxeon Star $30) on the side of the track, and a photo-diode on the bike (pointing left) with a band-pass optical filter. Pulse train the LED signal so you can try and eliminate the ambient light.

Fuck it...might just do the trigger idea .

the trigger is a great starting point. I might try that one myself.
If you are interested I'm currently tring out a set of j type thermocouples 1 is fitted to a large copper washer (mounted under my spark plug) to measure head temperature. and another 2 that are bolt mounted in the 1 in the intake and another on the header. a company in auckland makes them about $30. they seem to be very stable and linear and they will go to around 600 degrees happily. so logging them is very easy. (though I've got a CR500 campbell datalogger to play with) - why do this you may ask - because i can...

re the optical option - there are alot of guys in the states that use it for slot cars and/or remote control racing - same theory but they have up to ten units to one receiver. and use software to sort it out god knows how, but there is a couple of good web sites on how to build them cheap. i think i googled "lap timers cheap" and came up with about 10 sites.

[skelstar]

Bert: the unit recording the data and logging it will be on the bike, so you only have to have one transmitter. The unit on the side of the track is only a trigger source. I wont know what the times are or anything. Its a dumb unit.

The unit is primarily for seeing the time as you race. Bit of a distraction but hey. When the racer gets off the track, he can download the times by just plugging the unit into rs232. Spits the simply formatted data out to a terminal program.

Ta for the input.

[Bert]

Bert: the unit recording the data and logging it will be on the bike, so you only have to have one transmitter. The unit on the side of the track is only a trigger source. I wont know what the times are or anything. Its a dumb unit.

The unit is primarily for seeing the time as you race. Bit of a distraction but hey. When the racer gets off the track, he can download the times by just plugging the unit into rs232. Spits the simply formatted data out to a terminal program.

Ta for the input.

sorry my brain is one step ahead of the hand, where i was going with that was using that type of set up in reverse.
If they can measure up to ten different units - why cant you measure 10 different point on one track with one unit on the bike and still have your over all laptime and a break down of track segments times on download ?
but it's just a though away.

[skelstar]

sorry my brain is one step ahead of the hand, where i was going with that was using that type of set up in reverse.
If they can measure up to ten different units - why cant you measure 10 different point on one track with one unit on the bike and still have your over all laptime and a break down of track segments times on download ?
but it's just a though away.

Yeah good call. Def a market for that. I think thats something a seasoned rider would want rather than a young budding/trackday rider. Buggered if I could remember what technique I was using in the second lap through turn 3 .

Wonder if I can get this going for Trackday 3 in march? ....

[Racey Rider]

So a year down the road, Where are these Cheap Lap Timers?!
Why won't I be getting one in my Chirstmas Stocking this year?!

With all the Tect-o's on KB I can't believe we haven't been offered a <$100 lap timer yet.

[skelstar]

I seem to remember a distinct lack of interest.

...and couldn't couldnt be arsed.

[SwanTiger]

For $100 a session I'll time your laps.

[Racey Rider]

Fair enough. Maybe you allowed the thread to get too complicated with add on's.

I kinda had the idea of building a very low cost/budget lap timer. What Im thinking is purely having a box with a simple display on your handlebars and a trigger located very near one of your handgrips. Questions:

Would anyone be interested in buying one? (very low cost, not looking to retire on this product).

Is there something that already does this?

It seems Hoon had an option. But his link no longer works.

If I got 10 Kb'ers together to pay $100 each. Could a basic timer as above be made?
What are other people using?

Racey.

[notme]

Fair enough. Maybe you allowed the thread to get too complicated with add on's.



It seems Hoon had an option. But his link no longer works.

If I got 10 Kb'ers together to pay $100 each. Could a basic timer as above be made?
What are other people using?

Racey.

Dude,

I would do that for that money.....problem is that I would want to go back to some of the other ideas posted in this thread and make it all singing all dancing......

I think (after reading this thread that has resurfaced) that this idea has merit....will think about it over the weekend/xmas break.) I get paid to come up with solutions to problems like this, and have done many times in the past so I'm sure something can be done.