MagLev manipulator with feedback from 4 ultrasonic sensors to map a plane

Hi folks,

I need some help for a magnetic levitation manipulator project. The idea behind the project is that there will be fixed and a movable plate. Fixed plate will be consisting of a number of electromagnets, moving plate (levitated plate) will be consisting of a number of permanent magnets. there will be 4 to 6 electromagnet setup and permanent magnet.

I want to get an idea about how should I make an electromagnet, how to supply current to it (via an L293d based dc motor bridge, if possible) so that I can levitate the plate.

I'm gonna use 4 to 6 ultrasonic sensor (HC-SR04) each near an electromagnet, to track the position of moving plate. How can I map the data received form the ultrasonic sensors so that I can find the position of different points in that plane.

I'll be using the arduino mega board to control all these things. This is a project with time restriction. So, please friends help me with this in detail (as I'm a hardcore mechanical engineer) ASAP.

Thanks & regards,
Ahamed P

Magnetic levitation is already done in one of those project groops, Github or someone else. The distance sensor they usef was a Hall sensor and PID control of the electromagnet. I am not sure that an ultra sonuc sensor delivers data fast enough.

Railroader:
Magnetic levitation is already done in one of those project groops, Github or someone else. The distance sensor they usef was a Hall sensor and PID control of the electromagnet. I am not sure that an ultra sonuc sensor delivers data fast enough.

And, you have to wait for one ultrasonic sensor to receive an echo before you can pulse the next one.

Paul

Thank you for your response @Railroader @Paul_KD7HB

Okay the delay of the ultrasonic sensor is not a problem because, I am trying to make the syatem as a open looped one. Just help me to make the elecromagnetic coil. I've made one, but N and S poles are not formed, instead just the coil is getting magnetized attracting ferrite based stuff. I've connected the coil directly to a 9V battery.

Help me to make the coil and also to use 3 ultrasonic sensors to map a plane which can be used to find the coordinates of any point in that plane.

I've attached an image which shows the model of the project, just for your understanding. Please respond with this context ASAP.

Thanks & Regards,
Ahamed P

Top Plate (floating) with permanent magnets.PNG

Total Assembly.PNG

Hi,
Welcome to the forum.

Please read the first post in any forum entitled how to use this forum.
http://forum.arduino.cc/index.php/topic,148850.0.html .

Can you tell us your electronics, programming, arduino, hardware experience?

Thanks... Tom.. :slight_smile:

Trust me on this! If you have a coil of wire and apply a voltage to it, you HAVE an electromagnet with North and South poles. Always will. Can't have it any other way.

Describe your coil and electromagnet. Using a 9 volt battery to create an electromagnet is ridiculous. You might have a magnet for a few seconds.

Paul

The magnet can of course be shaped lika a horse shoe but one end will be a North and the other end be a south. The only way to awoid this is to have a circular iron core, a toroid, but then You will most likely not get what You want.

Thank you for your response @TomGeorge @Railroader @Paul_KD7HB

Okay these are the details. I'm using Arduino Mega as the controller. I'm using L293D based motor shield to control the intensity of the magnetic field. To begin with, I've just wounded the copper coil around a bolt (insulated, 2.5" length, refer diagram) and connected the two ends to a 9v battery just to check its working. A very little magnetic field has been a formed attracting the currency coins. But to find the poles of it, I just used a permanent magnet. I used the same side of the permanent magnet on the two sides of the electromagnet both sides are attracted by the electromagnet (no repulsion is spotted).

What is the mistake I've done here. Is it the 9v battery which caused the problem. Please respond ASAP.

Please help me to calculate the Voltage, Current required for controlling/generating magnetic field in an electromagnetic coil with n number of turns.

Also, as @TomGeorge asked, I'm extremely bad with programming I've planned to use the motor control program through L293D bridge circuit (using pwm values) to control the intensity of the magnetic field.

Thanks & regards,
Ahamed P

Arduino Mega.PNG

L293d based motor shield.PNG

Hi,
Are you aware that the HC-S04 is only good from 2cm to the target and no closer.
This is due to the switch time from TX to Rx of the control circuitry.

Tom... :slight_smile:

ahamedmusthafa33:
Okay the delay of the ultrasonic sensor is not a problem because, I am trying to make the syatem as a open looped one. Just help me to make the elecromagnetic coil. I've made one, but N and S poles are not formed, instead just the coil is getting magnetized attracting ferrite based stuff. I've connected the coil directly to a 9V battery.

Can you post a picture of your coils please?
How do you look for N and S poles?
What is "ferrite based stuff", you would need to use a magnet to to check the electromagnets poles.
Tom.... :slight_smile:

I asked Google "how to make electromagnet" and got over 6.5 million responses. Surely you can do the same.

Paul

TomGeorge:
Hi,
Are you aware that the HC-S04 is only good from 2cm to the target and no closer.
This is due to the switch time from TX to Rx of the control circuitry.

Tom... :slight_smile:

Yeah @TomGeorge, I've read the limitations of using ultrasonic sensor in google as well as the image you have posted. But other sensors suiting the application are a bit expensive compared to ultrasonic sensor (An ultrasonic sensor costs just around 1.5 USD, that is why I've preferred ultrasonic over the others). I've compromised just because I'm trying to achieve a higher levitation/floating gap between the fixed and movable plate. You may refer the figure for better understanding of what I'm trying to say.

Please suggest other sensors so that I may consider it, if it suits my budget plans.

Thanks & regards,
Ahamed P

MagLev Manipulator.PNG

TomGeorge:
Can you post a picture of your coils please?
How do you look for N and S poles?
What is "ferrite based stuff", you would need to use a magnet to to check the electromagnets poles.
Tom.... :slight_smile:

Yeah sure, I've linked the picture of my electromagnetic coil. Please refer the image linked with this message.
Right now I've successfully checked for the availability of N & S poles using a permanent magnet. And the good thing is, it worked. It has just drawn about 2V for its working (Earlier the problem was connecting it to a 9V battery, as you mentioned). Also the repulsion is not that strong as I was expecting. I just want to know the relation for calculating the number of turns and strength of magnetic field. I've googled but it was too complex for my level to understand. Please refer a link for easier understanding if you find one.

Thanks & regards,
Ahamed P

Paul_KD7HB:
I asked Google "how to make electromagnet" and got over 6.5 million responses. Surely you can do the same.

Paul

Yeah finally this helped. I've seen an Youtube video to understand the process better. Earlier I've made a mistake by using a raw copper wire which turned into a heating coil instead of an electromagnetic coil.

Now I'm clear with the making of electro magnetic coil. But I have some theoretical doubts like how much number of turns and its supply requirement required to generate a certain amount of force (repulsive force preferably). Help me on this because, google confuses me a lot on this.

Thanks & regards,
Ahamed P

ahamedmusthafa33:
Yeah finally this helped. I've seen an Youtube video to understand the process better. Earlier I've made a mistake by using a raw copper wire which turned into a heating coil instead of an electromagnetic coil.

Now I'm clear with the making of electro magnetic coil. But I have some theoretical doubts like how much number of turns and its supply requirement required to generate a certain amount of force (repulsive force preferably). Help me on this because, google confuses me a lot on this.

Thanks & regards,
Ahamed P

The metal for you magnet looks an awful lot like pot metal, not iron.

Find a source of the thinnest steel/iron wire you can find. Also find a cardboard tube. The length of a toilet paper core is right, but not that big in diameter.

Also find a supply of magnet wire. #22 AWG or #26 AWG, or similar. Wind as many turns on the core as you can or until you get tired. poke the two ends of the wire through the ends of the tube. Count the turns and write the count down.

Now begin to cut the iron/steel wire into lengths that match the tube. You will fill the tube with the wire pieces. Stuff as many as you can into the tube.

Now you can relate the # turns, the amps going through the coil and the magnetism you produced.

Paul

Finally, now you can apply power to the coil and see how much magnetism you have. Measure the current.