Let's Make Robots!

ThunderBird 6 - Gold-Coin-Ring-BottleTop-Finder

Autonomously looks for Treasure

yellowblackvertical.jpgThunderBird 6 -  Gold-Coin-Ring-BottleTop-Finder

So my latest Bot project is off the ground...... or should i say able to find out whats under the ground......

Objective (primary) :- Get a bot to follow a line of coins. ie line following with a difference.

Objective (Secondary) :- To find treasure..........lots of it ...... all by it self........

Objective (Thirdary) :- Self Funding ... able to detect enough money to Fund its self.

How :- Fix a Hacked Metal detector on to a servo that scans left and right and also Up and Down.

The Up and down is a stepper motor with linear guide-rail hacked from and (old) A: drive floppy disk.

Spin Offs :- It will wander around the garden/beach Autonomously looking for gold/silver/coins etcetcetc.


The Following is a progress of the project so far , just pictures for you to drool over.........

The Hacked Metal Detector is mounted to a scanning servo which is mounted to a linear up/down stepper motor.

Code-ing for stepper motor and servo scan works fine - motor drive now working.

 NextToDo:- Metal Detect Strategy











































 Basic SetupMentalDetective1__11_.jpgMentalDetective1__1_.jpgMentalDetective1__4_.jpgMentalDetective1__6_.jpg








   Coil protected by Plastic cover

 You can also see quite clearly the A: Drive Stepper motor top right

 The Stepper raises and lowers the probe assembly.

 The probe is fixed to a Servo so able to scan Left and Right.
























 The Metal Detector consists of 2 separate detetor coils wound around a ferrite rod.

 The Circuit is a Beat Frequency Oscillator - able to detect metal and also live electrical cable.

  The Beat-frequency oscillator (BFO) is the simplest type of metal detector.

The basic beat-frequency metal detector employs two radio frequency oscillators which are tuned near the same frequency. The first is called the search oscillator and the other is called the reference oscillator.

The outputs of the two oscillators are fed into a mixer which produces a signal that contains the sum and difference frequency components. This signal is feed to a low-pass filter removing the harmonics. As long as the two oscillators are tuned to the same frequency, the output will have no signal.

When a metallic object disturbs the magnetic field of the search coil, the frequency of the search oscillator shifts slightly and the detector will produce a signal in the audio frequency range.



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I like how after reading this entire discussion you leave us hanging toward the revealing of your track solution with even a photo!


This is an awesome idea. Id be hanging at the beach letting this hing patrol all day... close by with a shovel of course!


Awesome work.

Thanks for you comments - prepare to be gobsmacked................ 

TB-007 is here

What may you ask is up with TB6 - good question.

Well TB6 is under wraps  ---- undergoing a major Chassis UpGrade thanks ezekiel181 for the impulse.

TB6 will emerge as TB 007 over the next few days.




After intensive testing in the "Sand Box", a major problem emerged ----- that was that the YDM tracks kept picking up stones which it proceeded to crush - well YDM tracks are not exactly designed to crush. So when one track was jammed it would have great fun just turning circles...

So i needed something with a bit more substance.

Which will be unveiled over the next few days.




Very nice bot....  metal finder... jeje...I think it's time to built a special shield, because two Arduinos it's expensive and need two batteries, so more weight, the Mega solution could be useful, maybe using the Mega Proto Shield  http://blog.makezine.com/archive/2009/03/first_shield_pics_for_arduino_mega.html and Mounting both (wave shield - circuit motor shield - metal circuit detector) of the Duemilanove shield on it, will work.

Cool work...


Thanks for the ideas.

My present Wav shield is not Plug and play on the Mega - it requires hardware mods ie pin snipping and rewiring - plus there are issues with the libraries - i am holding back the mod for the moment.

Apparently the motor shield is mega compatable provided the latest library hack is installed (i have not tested yet).

To intergrate both onto a shield would mean re-design of one the shields (the motor side would be easiest). and at a guess would need only a small tiny shield attached to the end of the megas digital header (22-53)

TB6 was put to its paces in the "Sand-Pit". See Video above.

We placed coins and metal Bottle-tops 1cm under a flattened sand base.

TB6 made light work of detecting the objects. 

I was glad i made the videos - now i can see where it need more work.

It moved fine on the sand, however its tracks ocassionaly picked up small stones which would jam the drive mech.

Anyone know of some good tracks or another alternative ? 


Gareth! I just seen the last video and I'm impressed!!! Really a good work.  :)

You might want to think in hacking an rc-tank like this, or this.

Or maybe the Lynxmotion systems.

OR, if you want to go for a really expensive and high professional chassis, this are my favourites - the machine lab   :D

Thanks for the impulse and links ......

....... i started thinking after checking your links  ........ as much as i like the compact design of TB6 , i know at some stage it has to "Go up a Notch"........ more in the rough terrain direction (2in tank tracks or 4 wheel drive)

....... or another idea is to improve the mechanics of the Front end metal detect part ..... and make it universal so that it can be attached to "any" Robotic Vehicle ....  even a simple "Offtrack" remote controlled car (automated of course).

Ah yeah, those tracks will catch lots of little things driving over loose surfaces. Wheels would be easier and less maintenance. Tamiya have a few cheap off road tyres like these, or you could try the tamiya track set, it doesn`t have independant links that will pick up rubbish.

I can`t believe how cool this robot is turning out.

Or......shhhhhh i could just attach the detector to a tamiya r/c car...........

Yes i agree wheels or maybe 4-wheel drive would be better on sand or small stone particle ground.