2 replies to this topic

[jsnmc]

Hi all,

 

I am looking to make a gate that works like the easy pass system where a vehicle will go through and we can record the id and any additional calculations.  The two requirements are to keep the cost low and to be able to handle multiple vehicles in the gate at the same time at high speeds.  I am thinking of going the route of XBee with a dedicated RX and TX per vehicle.  GPS would be nice to have, but I am not sure if cost would allow and the resolution of the low cost gps wouldn't be very accurate.

Any ideas would be appreciated or if someone has tackled a similar project, please direct me to it.

 

thanks,

-jsnmc

[Chris Walker]

Hi jsnmc,

Have you also looked into RFID and other passive- and active- RF identification technologies? Often the systems just need to know the "tag" number and then they calculate everything else on the gate itself.

XBee would be cool too since you could do active communication and additional logic on the "tag" end too...although it might be a wee bit overkill. Then again...overkill has its advantages too sometimes

Chris

[jsnmc]

Hi Chris,

 

RFID was the first choice but there are a few questions that come to mind.  Price and availability of active RFID or long range readers came to mind.  I couldn't find many readers for sale at the typical electronic stores - I saw many on places like http://www.alibaba.com and what not, but I wanted something that was supported in more of a local fashion and maybe some that others have tried with the Netduino along with some code samples.

 

I also don't know much about how the active RFID works and could not find a great deal of information.  For my project the vehicles are  coming in the gate somewhat fast and possible at different angles and orientations.  I see that the easy pass gates are mostly aimed for a certain range of angles.  I think that RFID is possible because I know that commercial time systems are available for things like bike races and marathons.  It would for sure be a lot more simple than my XBee approach, but I am also thinking long term where GPS may be incorporated so have the Netduino and XBee on board might not be a bad thing as you eluded too.

 

If anybody has any comments on those points, I would appreciate hearing them.

 

thanks!