Wednesday, May 11, 2011

Neil & Inness Week 7

This week we encountered a problem with compatibility regarding the hardware we were planning on using. Our intent was to combine a wii nunchuck accelerometer to sense tilt degree with a compass the sense direction, in order to initiate and select transmitter for receiving. Unfortunately both devices used the wire.h library, which depends on the analog input pins A2-A5. Looking into this library we couldn’t find any reference to these pins so that we could change them, and because we couldn’t have both devices using the same inputs, we’ve given up on using the nunchuck in favor or a more simple tilt sensor.
Due to the fact that we now have to wait for the tilt sensor to combine its functions with the compass, we decided to instead focus on writing the code for the compass, and ended up dividing the 360 degrees of the compass between channels A, B and C. Because we still only have one transmitter it can only work for one channel at a time, but the set up seems to be working.
An additional challenge we must address is the fact that when there is no signal being received by the receiver it makes an obnoxious beeping. This is a good feature for a baby monitor as the user needs to know if he or she is receiving data or not, but for us a pitcher that beeps when it isn’t transmitting would all but ruin the fun of our device. Therefore we need to use a transistor with a battery-operated power-source to turn off the receiver when it isn’t activated. We believe this coding should be relatively simple.
Our main focus going forward is building the pitcher. Our plan is to buy a clean, simple looking pitcher and attach a base in the bottom to house our hardware. This base will have to be weighted to keep the pitcher stable, and we will probably do some soldering to make our boards and wires as compact as possible.

No comments:

Post a Comment