Build a Simple Robotic Metal Detector (part three)
Building a BFO Metal Detector
Here is a list of parts that you will need to build your metal detector. For this project I am connecting the metal detector to an arduino programmable controller ($30.00 from RadioShack). If you want to build just a regular metal detector that just makes sound all you have to do is replace the arduino with an 8 ohm speaker. This is also a handy thing to keep in mind if you have to troubleshoot this device.
At this point you will be assembling the circuitry of the metal detector. You will need all of the following items from the parts list along with a robot to install your metal detector on when you have completed this series as this tutorial assumes that you already have a robot.
- Parts list:
- Any 9v battery
- Small Gauge Copper Wire (J1, J2)
- 2x 220uF 16v electrolytic capacitor (C11, C12)
- 5x 0.01uF polyester capacitor (C6, C7, C8, C9, C10)
- 0.1uF polyester capacitor (C1, C2, C3, C4, C5)
- 10k 1/4 watt 5% resistor (R1, R2, R3, R4, R5, R9)
- 2.2m 1/4 watt 5% resistor (R6)
- 39k 1/4 watt 5% resistor (R7, R8)
- 2N2222A transistors - almost any NPN transistor will work (Q1, Q2, Q3, Q4, Q5, Q6)
- Arduino Uno
- Basic Stuff: wire, solder, soldering iron
- Search coil (I1)
- Reference ocilator (I2)
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| (Click on this image to view it larger) |
Completing the circuit:
(Click any image to view it full screen)
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| Line up the parts with the corresponding symbol on the schematic. |
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| connection points to larger parts. |
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| Fully assembled circuit. |
I'm trying to do this project but I don't read circuit schematics very well. Can you post a clean picture of a completed board or a video of it connected to the arduino and working?
ReplyDeleteSure, I will try to get that information uploaded sometime between now and next weekend.
ReplyDeleteAlright, new photos have been uploaded. Sorry about the wait. I since I only have one Arduino I was going to try to set everything up again to demonstrate it working but I cant disconnect the Arduino from the robot to have it in the pictures as I currently have it set up so I just labeled all the wires with where there suppose to connect to. Let me know if you need anything else.
ReplyDeletewhat's the maximum range of detection?
ReplyDeleteand what I want to detect using this setup is a cube of 10cm
ReplyDeleteThe range of detection depends greatly on the design of the search coil. My search coil detected metal objects of different sizes between 5 and 7 inches away. It would be pretty easy to make a few different coils and test out which works best.
ReplyDeleteThanks for ur help :)
ReplyDeleteThanks for this wonderful post.The information out here is very informative.
DeleteIf i want to build just a regular metal detector what about 1 and 2 the arduino power what shall i do with them
ReplyDeleteI should have made this more clear. The arduino power 1 and 2 do not correspond to the 1 and 2 that are labeled connect to arduino. Just ignore my plugs in the schematic. All you have to do is make sure that the arduino has power and then connect the positive wire(1) to a digital pin on the arduino. The negative wire (2) goes to GND.
ReplyDeleteThanks for the info
ReplyDeletebut here's what I get from what you've said and please correct me if I'm wrong that I just connect the end of the wires of "arduino power" to each other (nothing is connected between them)?
and what if I want to connect a speaker and led with arduino connected can I'd just connect a speaker to one more pin and add the same code for it ?
one last thing if I used 0.5 mm copper wire instead of 0.25 how would this affect the magnetic field of the wire?
finally thanks again for you amazing work :)
Almost, "arduino power" is just your regular arduino power supply. Those wires do not get connected together They go to a power jack on the arduino.
ReplyDeleteI don't know about a speaker connected to the arduino but I tested this using a buzzer from Radio Shack ($2.19) and that worked perfectly and an LED could easily be added as well.
Also thinner gauge wire works better but you should be fine using .5
If you have any more questions let me know, I realize that these posts need some clarification and I will try editing them so that they are more coherent.
I think I didn't make the first question clear to you
ReplyDeleteIf I intend not to use arduino what should I do with this "arduino power" wires?
Nothing, you can leave them off, don't connect them together either.
ReplyDeleteabout j1 &j2 do i have to put a jumper or normal wire ?
ReplyDeleteNormal wires
ReplyDeleteThanks for sharing the nice post..
ReplyDeleteVery nice but i think you should get a breadboard for xmas :D
ReplyDeleteUnderstandable, this is an old project and I have been meaning to redo it.
Deleteis R6 2.2 milli ohms or 2.2 megha ohms
ReplyDeleteIt is megaohms.
Deleteyou can send me a scheme and more instruction to make a metal detector? please send to madalin_ionescu_21@yahoo.com
ReplyDelete