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How to take acute angles using qtr 8A rc for a line follower


Actually I want to develop an fast line follower that can take 90° and 45° more accurately,their are lot of line follower competition is going on here if only I could win these if my bot is more accurate in taking angles …also I want a sample program to run the bot on white line on black surface, currently now I m using a Audrino Uno and motor sheild,Bo motor qtr 8a rc . If any one could answer this and give a sample code



Since the line following algorithm would depend on many factors of your robot (e.g. motor driver, motors, diameter and distance apart of the wheels, battery voltage) as well as your line following course, an example program would not be practical. You might be able to use the sample code in the “Advanced Line Following with 3pi: PID Control” section of our 3pi Robot’s users guide to get an idea of how to structure your code for PID control. The LineFollower example program from our Zumo Robot’s Arduino library might also be a useful reference. However, please note that the QTR sensor functions are slightly different in our QTR sensor Arduino library.

In general, there are a lot of factors that can change how well your robot can follow a tight turn. If you are talking about sharp 90° turns (e.g. not smooth and with no radius), that is something that is commonly handled by breaking out of your main line-following algorithm. For example, when a right-angle turn is detected, the robot can be programmed to perform a pre-programmed 90° turn before going back into its line following algorithm.

By the way, “qtr 8a rc” does not match the name of any of our QTR sensors. It sounds like you are trying to refer to either the QTR-8A or QTR-8RC.