Flawed IR Design Confirmed

[EricVanWyk]

Originally Posted by RyanN

Team Fusion had their first try with the IR board mounted on the robot this evening with bad results. Here are the problems we encountered:

• With the programming, the digital input must be 1 in order to count it as pressed (this is bad because if one of the cables comes loose, it will result in a robot without any sense of where it is going)
• Very gittery unless you run the motors for about 10 loops, then the robot drives for a few hundredths of a second before it stops.
• The board will fry itself after a few minutes.

Yes, that's right, we fried our board, and I can't figure out what is wrong with it. The 5V regulator is putting out exactly 5 volts, the wires feeding the IR board are wired properly and working, and it WAS working perfectly.

We're not sure what happened, but while driving it, it all of a sudden took off on its own, hit our unwelded frame against a concrete wall. My first thought was it was a dead backup battery, and this was indeed true, so I replaced the battery with one reading about 7.8 volts, and it did the same thing, smacked into the wall. So I declared that we had problems and started to investigate, and yet, I found nothing wrong. I think we have it on video too of it going spastic on its own.

I definitely think there is a flaw in the design, a very dangerous flaw as the robot will all of a sudden start running on its own. Another flaw, if one of your wires comes loose, it will drive on its own. I'm going to contact FIRST and see what their conclusion is.

Ryan, remember that you will receive a series of pulses when the board is getting a signal. If you tie that input directly to a victor, you will see a series of pulses on your motor.

The IR board is to send commands, not state. Put a software latch or low pass filter in.