Help Required for Multizone Walk Through Gate Project

[Rizwan Zafar]

Dear all,

I am an Electrical Engineering student at National University of Sciences and Technology, Pakistan. I want to start my final year project of Walk Through Gate with multiple zones. I have a little study of the metal detection techniques e.g. BFO/IB/Pulse Induction and have implemented a BFO design in a semester project.

I have a theoretical understanding of how these techniques work but do not know how to use them in a Multi-zone walk through gate.

Geotech forums is a very renowned for helping students for their projects in metal detection. I also require help from this platform.

Kindly help me in 'where to start?' and 'how to proceed?'. I want to develop something of industrial standards.

Kindly help.

Regards,
Rizwan Zafar
National University of Sciences and Technology

[Rizwan Zafar]

I have seen on these forums that there are many kits available for metal detection. Pulse Induction is classified as the best and latest technology. Can any body guide me how I can get my work done with some of the available kits? I shall be grateful.

Regards,
Rizwan Zafar

[Carl-NC]

Here is a prior discussion on walk-through:

http://www.geotech1.com/forums/showt...ircuit-digaram

First, a multi-zone design is very aggressive, I suggest you back off to a single zone design. Second, BFO is wrong for a W/T design, most all designs are PI. A single-zone PI design will be harder than you think, especially if it's your first ever metal detector.

- Carl

[Rizwan Zafar]

Thanks for the reply

Dear Carl,

Thanks for the reply.

I have gone through the link you have sent to me.

It still does not give me an idea about how to kick off and start working. As you mentioned that multi-zone design will be a tough one. Can you please guide me is it possible that I go with 2 zones only (Right/Left)??

Moreover I want to go with some of the existing kits. I studied about SURF PI kit and how to build a metal detector from it from the link below:

http://www.adrianandgenese.com/blogg...rom-a-diy-kit/

Will this kit be feasible to work with and develop a W/T design?? How will the coils be arranged??

Best Regards,
Rizwan Zafar

[Carl-NC]

See Post #61, start with making a normal PI circuit work with a TX coil in one panel and the RX coil in the other. Once you have that working then proceed to implement the other suggestions.

Yes, you can eventually get to a L/R zone detection but that's quite a bit harder.

Yes, practically any PI circuit can be made to work, until you try to implement bipolar pulsing.

[Rizwan Zafar]

Thanks Carl for the guidance.

But there is something confusing. Most of the PI designs here are single coil designs. But in that post you have mentioned Tx coil and Rx coil separately. And moreover those pics of the W/T are not much informative at the understanding level at which I am.
How can we use two coils separately?

And could you please specify any particular kit to be used so that I can order that kit??

Regards,
Rizwan Zafar

[Rizwan Zafar]

Kindly somebody guide me

[Carl-NC]

Practically any PI design can use separate TX & RX coils. See HH1-RevD and HH2 projects for examples. Place the TX coil in one panel, the RX coil in the other panel. While the TX coil should be low inductance (~250-500uH) the RX coil can usually be higher (1-2mH or more).