Understanding Issues

[FerdinandWittmann]

Hi,
i am new to robotics and having been trying to implement this. My circuit works but i can't figure out how i can detect negative and positive values, so i actually now if i am inside the loop or just near.
Also if you have a couple of free minutes, if you could try explaining how the circuit works a little more in Detail.
Thanks already for contributing this interesting project.
F.Wittmann

[dzlonline]

Hi. The circuit only detects signal strength. I do not understand what you mean by negative values. The magnetic field inside a (circular) loop of wire is nearly constant. Close to the wire (much less than the diameter of the loop) the field rises sharply, becomes zero right on top of the wire and then tapers off quickly outside the loop with the distance squared. By comparing the measured signal strength to the average signal strength inside the loop you can tell if you are inside or outside the loop. If the signal falls below some pre-determined threshold (e.g. 75% of the signal measured at the center of the loop) you are outside. The angle between the loop and the pickup coil also greatly affects the measured signal strength, varying between zero and 100% between an angle between zero to 90 degrees. You may set the threshold so low that just a tiny amount of signal registers as "inside" the loop. This will allow a great variance of the pickup angle while still giving a valid inside/outside reading. Since the signal tapers off very quickly outside the loop the false "outside" reading will typically be quite acceptable. Dzl

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On Fri, Jul 28, 2017 at 1:11 AM, FerdinandWittmann ***@***.*** > wrote: Hi, i am new to robotics and having been trying to implement this. My circuit works but i can't figure out how i can detect negative and positive values, so i actually now if i am inside the loop or just near. Also if you have a couple of free minutes, if you could try explaining how the circuit works a little more in Detail. Thanks already for contributing this interesting project. F.Wittmann — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#3>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AD9xSLkgJ0__ErRL_-YSSGC-01T_xsM5ks5sSRkIgaJpZM4Ol8x1> .