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Re: vEx PWM Motor Response
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Originally Posted by Gdeaver
One note about driving the vex straight with encoders. There appears to be some latency with the encoder read block. Try toggling the order of the encoder reads. Read right encoder then left, take action, read left encode then right, take action. I was able to get consistent straight runs of 20 ft.
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Thanks for the suggestion - I tried that - You or someone else gave me that hint before.
My machine would straighten itself each time its heading got off (detected by counting encoder tics); but the asymmetry in the CW and CCW motor response curve meant that it would slowly drift sideways each time it would slowly turn away from its intended heading and then more quickly compensate to return back to its intended heading.
Using EasyC to fix that (with proper timing of the sensor reads, filtering of the sensor data, accurate calcuation of position and heading, and feedback control of the entire system) was too much like sticking my finger in a light socket....
:-)
Blake
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Blake Ross, For emailing me, in the verizon.net domain, I am blake
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