I did a little searching on threads from previous years. In the past people have monitored input switches on the operator interface, and seen switch-bounce.
I was thinking perhaps IFI filters the switch inputs, but from what I have been able to find so far, they dont. Unless someone does further testing, or IFI comes up and says they have debounced the switches in the interface, I would design your systems to debounce the switch inputs (user interface and on the robot) if your application requires knowledge of single-push button actions.
from a thread in 2004:
Quote:
Originally Posted by maxlobovsky
This may or may not be related, but i have found that lots of joystick buttons seem to flicker IE not giving a constant stream of 1's when they are being pressed. Our code now checks the button over the period of 3 or 4 frames to make sure its really pressed. This is probably a good idea for a winch button anyway, you wouldnt want it accidentally pressed.
Originally Posted by KenWittlief
wow! im impressed that you discovered that by yourself!
Its called 'switch bounce' - when you close a switch or pushbutton it takes about a 1/10th of a second for it to make solid contact - the surfaces actually do bounce a tiny bit - so if a fast microprocessor is polling the switch it will see it go 00001101010011110111111011111111111
and your timing is right - 3 frames is about a 100 mS
nice catch!
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