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cdog4w
2011.11.05, 01:29 AM
Hey everyone, I thought I'd post my recent project. I took a trackmate racing iridium lap timer and used a bluetooth module to go wireless between it and the computer running the lap timing software.

The whole thing is powered by a 2c lipo and is in a project box, neatly contained. One wire goes out to the overhead sensor and that's it.

The real advantage will kick in when I write an android app and ditch the laptop. I'll start with a basic lap timer, then start adding features. First will be audio announcements that you can listen to over headphones or phone speaker. I also think it'd be neat to integrate the phone camera so you can take a picture of the layout, maybe include car setup info so that you know exactly what the laps were run against.

Pics here: https://skydrive.live.com/#cid=FBB038ABE8FC6DFF&id=FBB038ABE8FC6DFF%211214

Gonzo007
2011.11.05, 11:25 AM
Very cool. That is a great for our local mini z club.

arch2b
2011.11.05, 12:01 PM
this is great for me at home! hook to my phone (if iphone version is possible at some point) and run laps at home for practice.

cdog4w
2011.11.06, 01:50 AM
No plans for iPhone. I'd need a iPhone AND a mac (no windows iOS development), I'd need to pay a developer fee (and I already have developer accounts for android/wp7) and I'm not particularly interested in their platform :(

I'd be doing this for wp7 but they haven't rolled out the BT apis yet.

On the upside for you, androids are everywhere and it'd be super easy to snag a cheap handset for dedicated use for $50 or so. Android tabs would be even cooler, could run full races no problem with their larger screen. Or add a pico projector? :)

For reference, the project cost ~$50 for the BT module and the few parts needed to do the serial level conversion.

I'd be super tempted to snag that $50 portable thermal printer at sparkfun if our club used trackmate (unfortunately, they picked i-lap, doh). Good system, but I have a trackmate setup and the transponders are a good bit cheaper. (http://www.sparkfun.com/products/10438)

color01
2011.11.06, 05:34 AM
Go cdog! Let me know if you need a tester. :D

mini-z
2011.11.06, 08:17 PM
Nice hack cdog4w! I was so going to bust you RE Android vs. WP7 but makes sense due to BT API! I'd be up for assisting w/ the iOS client if you like, though I have to admit it wouldn't be my top priority project right now. :) How widely used is this lap counter - just curious as to potential user base for mobile clients? In addition to the barriers you list, Objective C is quite a steep learning curve assuming you spend all day in VS - and the Xcode IDE isn't a patch on VS IMO...! :)

cdog4w
2011.11.06, 09:31 PM
Nice hack cdog4w! I was so going to bust you RE Android vs. WP7 but makes sense due to BT API! I'd be up for assisting w/ the iOS client if you like, though I have to admit it wouldn't be my top priority project right now. :) How widely used is this lap counter - just curious as to potential user base for mobile clients? In addition to the barriers you list, Objective C is quite a steep learning curve assuming you spend all day in VS - and the Xcode IDE isn't a patch on VS IMO...! :)

This is literally just a passthrough of the trackmate's serial data, so you wouldn't need anything from me to write an app. It's compatible with one of the AMB formats, so it shouldn't be too difficult. Looking at the flipside codebase would be a good start if nothing else (thanks for making it OSS pinwic!)

Iridium is in a lot of places because it works great but is super cheap. You can get all the bits you need for timing on RCP (including 1 transponder) for $150. That said, the price is quite steep for one off personal use, especially if you have to add another $40-50 for BT. I doubt many people will pursue this, so I'm primarily writing the app for myself :) It *is* a heck of a lot cheaper than this guy however: http://www.dirtchampdesign.com/newsite/
($399 Euro, ~$550)

I think another interesting take on it would be to push data from the central lap timing computer at a normal track to phones of all the drivers, instead of just being able to hear your practice lap time (which gets messy with short laps on RCP tracks), you get the actual data pushed to your phone, can filter out all but your lap times etc. I eventually want into adhoc wifi networking for this purpose.

mini-z
2011.11.06, 09:36 PM
OK maybe we should talk, as, the reason I was curious about your project is more related to the latter point you make there... :D

cdog4w
2011.11.07, 01:54 PM
OK maybe we should talk, as, the reason I was curious about your project is more related to the latter point you make there... :D

Well, I found one piece of the puzzle last night: http://com0com.sourceforge.net/

Splits the incoming laptimer serial signal into 2 virtual ports so it can be consumed by the official lap timer software and then by a server that will push the data to phones (over wifi somehow).

I-Lap
2011.11.08, 01:59 PM
I think another interesting take on it would be to push data from the central lap timing computer at a normal track to phones of all the drivers, instead of just being able to hear your practice lap time (which gets messy with short laps on RCP tracks), you get the actual data pushed to your phone, can filter out all but your lap times etc. I eventually want into adhoc wifi networking for this purpose.

Ideally this should be an open standard that could be adopted by authors of various timing softwares and phone/tablet apps. Then regardless of what timing system, software and phone are used, end users can easily get the data they want.

I can't tell from your pics which bluetooth module you are using. Does it have any built-in failsafe such as ack/retries to verify the lap info makes it to the computer?

If anyone wants to try this with an I-Lap decoder, I can provide the info for where to tap in on the board, etc.

Nice project BTW.

Craig

cdog4w
2011.11.08, 02:35 PM
Ideally this should be an open standard that could be adopted by authors of various timing softwares and phone/tablet apps. Then regardless of what timing system, software and phone are used, end users can easily get the data they want.

Couldn't agree more! I got the impression most lap timers sent serial data in an AMB compatible format so that they are compatible with as many lap timing software packages as possible. That said, I'm sure there are quirks worth noting between the manufacturers and having an intermediary data layer might make sense.

I can't tell from your pics which bluetooth module you are using. Does it have any built-in failsafe such as ack/retries to verify the lap info makes it to the computer?
http://www.sparkfun.com/products/10269
I don't think so, this is literally just taking the serial output and pushing it through the BT link. No uc to do packet based communication. Unless it's built in to the BT SPP protocol?

If anyone wants to try this with an I-Lap decoder, I can provide the info for where to tap in on the board, etc.

Nice, always great to see product owners supporting their product top down. I might be pinging you in the future as we use I-Lap for our work race club (about to order a personal transponder too :))

cdog4w
2011.11.18, 02:32 PM
Update! Wrote a basic android app to connect to the lap timer and display laps. Currently does best lap and current lap as well as recording the number of laps (i.e. practice mode). I also hooked up text to speech, so you can drop the phone in your pocket after connecting and it will read lap times to you via headphones.

Video here: https://skydrive.live.com/#cid=FBB038ABE8FC6DFF&id=FBB038ABE8FC6DFF%211232

So I need:

phone
lap timer box (link to pic above)
something to hold up the overhead sensor
radio and car


That's it, and it will easily fit in most mini-z sized pit boxes! It will be able to (eventually) run full races... from my pocket :)

arch2b
2011.11.18, 04:32 PM
very cool!:cool:

cdog4w
2011.11.22, 02:59 AM
A friend linked me to this: http://www.*******om/itm/Bluetooth-RS232-UART-TTL-serial-Converter-Module-Adapter-Daughter-Board-/150676839000?pt=LH_DefaultDomain_0&hash=item23150a1a58#ht_2681wt_1235

Not sure if it would work the same as the sparkfun module I got, but if so, it'd make the project cheaper by $30 or so :)

cdog4w
2012.02.28, 06:33 PM
Thought I'd post a recent test session:

https://skydrive.live.com/#cid=FBB038ABE8FC6DFF&id=FBB038ABE8FC6DFF%211490

Finally getting some more time to work on the android interface and have picked up a galaxy tab 7.0 plus in the meantime to use on race nights :) Much more convenient vs. lugging a laptop!

I did some more research into using a laptop to send personal lap data to individual phones (like the latest zround I think android app), but plan to finish the android full race software first.