Hey guys I have built a lap timer that trips when a bike rides past a laser shining onto a photo diode. The problem with this is that any bike can trip the laser. So now I want to use a transponder system that can distinguish between bikes. I want to put transponders on each bike to time each time individually. I do not want to use infrared sensors or anything because it's on a dirt track. I also want to use something (I'm guessing a transponder) that does not need direct line of site in order for it to trip?
What can I use and where can I find these components?
I don't think RFID tags will work, the tag needs to be too close to the reader and it reads relatively slowly so if a bike comes flying past it won't pick it up
Is there any possibility of two or more bikes passing the timing point very close to each other. That will make identification very complicated - perhaps only possible with a vision system that would require the power of a PC.
In recent decades of Olympics I've seen cameras running along side the game till the finishing line, deciding who went through first and by what fraction of seconds. I am not too sure what alternative is out there that needs no videos. Smart tags don't work as fast and as far as you need them to work. Simple sensors will NOT tell who and which.
If you want to reverse the role, you can, have sensors on each bike and wirelessly report to a central control when it passes an IR post or buried magnet etc. Will that work? Cyclers won't complain about a device attached to their bike?
It's dirt bikes. Two wheeled motorcycles with engines. I've already built the timer and write all the code. All I need is a trigger mechanism that can identify each bike from the other
AMB dominates this market. And all AMB users are to the point of universally hating them. They have proprietary products for every different type of racing from motorcycles to RC cars to gokarts to real cars. For no reason. There are some companies doing transponders that compete with the AMB ones and a few in progress projects (mostly from the RC racers) to make the listening side, but nothing good yet that I've seen.
There are a couple companies with overhead solutions for bicycle and running races, but again, complete proprietary systems.
If someone could create a decoder that could use existing AMB antenna loops and their own transponders and software, that person could make a killing.
djb_rh:
If someone could create a decoder that could use existing AMB antenna loops and their own transponders and software, that person could make a killing.
--Donnie
Or be killed by lawyer fees when then start suing for IP infringement. A completely open-source solution needs to replace or complement the current situation
The antenna is a loop is a loop of wire with a particular spacing and depth. There's no IP in copying that, but there is a ripe market of tracks that would rather not cut their asphalt.
RFID is still the right answer, but not the type that must "gather" RF, rectify, charge a cap, activate the uC, and transmit from the stored energy. You are looking for a design that is battery powered (active), listens, and transmit from within a very narrow receive area where the authorizing transceivers has a narrow antenna pattern. Every monitoring station would have an activation code which would time-date the bike passage through the zone. As we are taking about a single packet sent from each bike, the received must be capable of distinguishing (discriminating) very narrowly spaced, but separate signals in the event of two bikes very close.
The selection of an open frequency, the antenna design, and transceiver h/w creates a full package. Antenna should be rather simple, an advanced HAM operator would be a handy resource.
A Peach Pass is a small, thin electronic toll collection device similar to the GA Cruise Card that adheres to a vehicle windshield OR a bumper that mounts to the front of your vehicle. The Peach Pass is connected to an account established with the State Road and Tollway Authority (SRTA) that automatically deducts the proper tolls when using the electronic toll lanes of the I-85 Express Lanes and any future toll roads in the state of Georgia. - See more at: About Toll Violations - Peach Pass | Keep Moving
Well usually about 3 to 4 bikes at a time. As I use the laser now I have written the program to learn one bikes time within 2 laps. It just gets an average of those 2 laps. Then if any bike trips the laser and it's not within 5 seconds of that time it discards the time.
The only problem is the bike being timed must first do two laps before other bikes get on the track which is not always possible
Without wishing to be unkind to the OP this sounds like a project that was started without appropriate planning. What works for one bike does not scale to several.
The OP is in very good company here. There are many stories of $million failures among IT projects - especially in the health sector. However I doubt if the OP got a fat consultancy fee.
Robin2:
Without wishing to be unkind to the OP this sounds like a project that was started without appropriate planning. What works for one bike does not scale to several.
The OP is in very good company here. There are many stories of $million failures among IT projects - especially in the health sector. However I doubt if the OP got a fat consultancy fee.
...R
LOL, dude why are u talking in parables? Or am I just confused? Haha this laptimer works like a boss!!! I'm just tryna make it better
