Automatic Sensor Identification

I am designing an Arduino based DAQ for some middle school students. Currently the only hardware I am using is an Arduino Uno, and the Sensor Shield v4 (2 Pin XH2.54 Plug Connector Wire--200mm - emartee.com) My hope was that sensors could be plugged into the 5 analog ports that are broken out into connectors with 3 pins (Signal, GND, VCC), and that through some small trick the sensor could be identified by the arduino, and then labeled as such to be sent out through the serial port. Does anyone have any ideas on how to do this?

Thanks in advance,
Nathan

You need some way for the sensor to identify itself, and there's no obvious way to achieve that with the set of pins you have available which will support arbitrary sensor types. If you can come up with a concrete list of sensors that you want to support, perhaps a simple electrical solution would be possible.

Otherwise, one option is to include a microcontroller in each sensor and invent some sort of standard communication protocol so that the sensor can communicate its type, identity and value to the Arduino which could relay it to the PC. If you used something like an ATTiny it could be quite small and cheap, and would just need to contain enough logic to read whatever type of sensor it was integrated with and present the reading via whatever standard interface you choose to use. You might even choose to use a more complex Arduino which includes a USB port (there are some pretty small clones with USB capability) in which case you could eliminate the central Arduino and just have each sensor appear at the PC as a separate USB device.

Nothing springs to mind if you are using dumb sensors, especially if you are using sensors from all and sundry.

Some clever scheme along the lines of what Peter suggests will be required I think, and that means making all your own sensors.

Is that part of the brief? Is it worth developing such a scheme for the students? Maybe it is if this will be an ongoing teaching platform for the school.


Rob

nnfuller:
I am designing an Arduino based DAQ for some middle school students. Currently the only hardware I am using is an Arduino Uno, and the Sensor Shield v4 (2 Pin XH2.54 Plug Connector Wire--200mm - emartee.com) My hope was that sensors could be plugged into the 5 analog ports that are broken out into connectors with 3 pins (Signal, GND, VCC), and that through some small trick the sensor could be identified by the arduino, and then labeled as such to be sent out through the serial port. Does anyone have any ideas on how to do this?

Let's see. 5 sensors, connected to 5 analog pins. Hmmm.... let me think.

I have it! When you read the sensor on analog pin 0, send out the data, and identify it based on the number of the pin you just read!

Wait... Another idea! Do the same with analog pin 1, then 2, and so on!