IRRangefinder with I2C bus well that would fit quite perfectly to ourupcoming AeroCopter. Especially now that I have just finished my I2CESC's for this same platform.
The Sharp GP2D12 is an excellent, well proven sensor. Its analog outputmakes is reliable and inexpensive, but a bit processor-intensive to use with a microcontroller. Our DIRRS+ fixes
this by letting you poll it for digital output in any of 3 methods.
But when you're using multiple sensors, you can quickly run out of I/O
lines, or code-space to handle all the different sensors. Enter the I2C-It, a slave-mode I2C device!
The I2C-It lets you use the popular I2C / TWI (Two-Wire interface) to
string up to 8 sensors on a single I/O line! And by simply changing the
device address in your code, you can change which sensor you're asking
More information from Solarbotics website http://www.solarbotics.com/products/35080/