[PhilBot]

Originally Posted by jbbjjbt

Phil,
But sometimes either the encoders don't read or the loop processes to slowly and the robot goes way past where it is supposed to stop. It is somewhat random as it will work one run and not the next. It is frustrating and time consuming.

Have you seen this? Do you have any ideas how to fix it?
Thanks,

Hi

I still see times when for some reason the NXT stops being able to talk to the Motor controller. When it happens, it usually continues for about 2.5 seconds, and then corrects itself. Not helpfull if you are planning a complex sequence.

The encoders keep running insider the speed controller, but don't get seen by the NXT untill after the bus fault clears.

Are you keeping track of your 12V battery voltage? My experience is that these "random" problems occure much more if the battery voltage is let go below 13.5 V (some have said 13.75V)

This isn't a great lot of help, but we've just resigned ourselves to keeping the battery charged and putting up with random motions.

I'll say that we also get our best results if we power down BOTH the NXT and 12V betwen each run. It just "seems" to help. The glitch seems to occur whenever we forget this power-cycle step.

Phil.