i am trying to implement PID on a line following robo using ATMEGA32. i have seen basic things such as formula to implement it here:http://www.chibots.org/index.php?q=node/339
i am driving motors(2motors & differential turning) using varying PWM to each wheel. So my question is what exactly i am supposed to do with value of P+I+D i am calculating? my instinct says its somewhat related to varying PWM using that value. but in what way i can use that value to control two motors by a single value. can anyone guide me regarding this? any tips for efficiently tuning are also welcome. i also need guidance regarding terms such as overshooting, rise time etc. regarding line-follow context.

 

Here is a link to an article on the implementation of "fuzzy logic" technique for an autonomous robot such as your line-following robot.

You may want to look into this technique as an alternate to the PID approach.

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