I am building a GoKart track for my kids and the kids in my neighborhood using old stuff and some local funding. Yet I have a issue. I work as a programmer and am Arduino enthusiast and this is what I want: A timing solution for the Karts so that kids can get into various races..
Lets not get into detail, I know how to handle and work with data, yet I have to find a solution on how to gather them.
What I want is:
time 5 karts at a time
start/endtime is all I need
I was thinking:
some passive solution to ID every Kart (RFID, IR) ?
some sensor/antenna on the lap START/STOP
And my question is - what shall I use? I wanted and I have read a lot about RFID solution, and that was all nice.. I have chosen the UHF RFID version and chip, antenna - was okay but the READER is at arount 900bucks and that is way too much :(...
So I was thinking - IR maybe? I place some IRs on each Kart and than just analyze the light at START/STOP?
Could that work? If yes, could you please point me into the right direction? I could not find ANY tutorial to this
The problems that I am afraid of are:
two or more karts at the same time?
its outside - sun? could that cause problems?
how accurate is IR?
how big should the diodes be?
A tutorial, ideas, brainstorm - would be VERY apprecitated :)) Thanx...
If this should fail, I will go for the 1000+ bucks RFID solution but the Kids would have to wait a season longer
I just thought - arduino should be able to help me out hmm?
Thank you a lot!
P.S.: Should this help me out - Ill write a full blog about that :)) for the future
The requirements for lap counting and lap timing are different.
In motorsport lap counting is typically done using a trackside beacon and a transponder or logger on the vehicle. For cars the beacons are usually radio based in my experience.
There are specialist systems designed for use in karting which seem to come in around a couple of hundred quid per seat, which use IR or magnetic beacon. Some of these include estimated lap times although I'm not sure how accurate they are because they just rely on beacon proximity for the timing information. I'm sure that if you looked around, you could find a kart timing system that included an uplink to a central monitoring/scoring system.
If you want to make your own I suggest you look into how those karting beacons work - I doubt they are very complicated.
xoddam: could not find anything that could lead to a "unique" IR signal ... for multiple objects ...
does not have to be IR but I dont know any better
any thoughts?
At the point you want to detect them, how wide is your track (in cart widths)? Could there ever be 3 carts passing the detection point at once? If not more than 2, you could transmit an IR beam from both sides of the carts to both sides of the track. Even if two are passing the detectors at the same time they couldn't block each other's signals.
if you only plan on having 5 carts at any given time, why not align 5 photoelectric sensors (IR presumably) vertically and put a mast of different length on each cart. Cart 1 will disrupt only the lowest sensor, cart 2 will disrupt the lowest 2 sensors, and so on. Automationdirect.com has a number of IR sensors that are well under $100. It looks like the most capable sensor for your application is the cutler-hamer through beam sensor ( http://www.automationdirect.com/static/specs/e50pethrubeam.pdf ) with up to 500' range and a response time as low as 2ms. I don't see anything in the data sheet that states the sensors can not be used in daylight, but I don't see anything that says they will work in daylight, it might require a message to tech support to confirm.
I've never used IR sensors over long ranges, the beam spot is going to be fairly large at more than a couple feet, I'm not sure how large the mast would have to be to break the beam or how far apart the sensors would have to be to avoid interference. It might not be feasable.
how about a RF output on each cart with a different frequency.
at the finish line, you have the receivers looking at the finish line, so they will not pic up the signal until the cart passes the line ?
use the same frequencies as model airplanes ?
cart would have the signal only going strait up or sideways, the receiver would be set to only pick up through a slot at the finish line
xoddam: could not find anything that could lead to a "unique" IR signal ... for multiple objects ...
You don't need a unique signal - just a way for a given kart to detect when it has crossed the line so that it can announce "I just crossed the line" to your scoring system.
You can put the timers on the carts, bury a wire that you will pulse current through (makes a changing field) just under the start/finish line and pick that up with Hall sensors on the carts. The units don't have to be permanently mounted.
You can buy an Arduino per cart or you can build stand-alone AVR's, it's your time so either may be more economic.
Shop around, you can pay way too much for display units. You might only need a 4 digit 7-segment display but if you're going to get bigger ideas then look to 2 and 4 line LCD panels.
If you have tools and know-how, enclosures can be made out all kinds of things like PVC pipe.
Hello, I'm actually in the process of researching and attempting to develop our own system that will do this for a fun center that runs up to 18 carts at one time.
Looking to see if you have made any progression?
I'm thinking I need to go with a rfid or nfc type setup as i can have up to 4 carts pass the same spot side by side at a time.
and this is what I want: A timing solution for the Karts so that kids can get into various races..