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Movement Tracking

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I am trying to get my Wall-E to follow the color red. The problem is when it see's the red object it turns away from the object. I have everything set up as in the Roli exercise. If I uncheck the left/right turn box in the movement tracking, it will follow the object straight ahead.

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Hey Bob,
Are we talking about his pan and tilt head or his actually drive wheels that are turning away from the red object? For pan and tilt, you may need to invert the servos on the x and or y axis in the camera control... If he is driving left to chase the red object when he should drive right then you'll have to adjust this in the Movement Panel (the camera uses the Movement Panel to drive Wall-e left or right when movement tracking)...


The drive wheels are turning away.


Ok, I assume the Movement Panel works correctly when you use it manually? The camera uses the Movement Panel to control wall-e (when chasing the coloured object)... Go back to the camera control and adjust the grid lines to default values... The grid lines should look like a tic tac toe board so to speak... The camera needs to have grid quadrants clearly defined in order to movement track...



I have come across this a couple of times. A couple of power cycles of the EZ-B usually fixed it. And poor ambient lighting or having an object to close to the camera seems to have this effect also. One other thing, did you ever release your servos for some reason at some point, before doing any colour tracking? If so, try resetting the servo speeds.


One other thing I forgot to mention was one of the issues I had with this too. Depending on items in the cameras view and brightness settings, I came across a few false positives. For example, I have some woodern furniture and when testing colour tracking with a red cloth, the brown wood could sometimes be recognised as red (as seen in photo below) which would cause the servos to twich and turn the wrong way. Something to keep in mind.

User-inserted image


Thanks Richard R and Steve G. I deleted the Movement Panel and then set it up again and got it working OK. I haven't used this Wall-E program for a few months and a few scripts don't run properly. I don't understand why, I'm running the current software.
Thanks again for your help.