Confirming the Delayed Lenz Effect

[TinselKoala]

@Farmhand: The Allegro line of Hall sensors is my favorite, I've used them a lot and have a 3144 in my Marinov Slab pulse motor.

The Stamp, Parallax, and Arduino systems are all microcontrollers with interfaces and programming systems and they can all do pretty much the same things. Which you use will be a matter of taste and convenience, but I think any would work.
I like the Arduino system for several reasons, the programming environment uses a form of the c++ programming language which I know fairly well. Another is Arduino's use of "shields" which are stack-on special purpose boards like multiple motor drivers, ethernet, wireless, touchscreen, etc. that stack onto the headers of the main board.  I can't really compare directly as I have very little experience with the other systems. Stamp is used for robotics a lot, and is the oldest system, I think.
Many of the Stamp and Parallax peripherals can be used with Arduino, for example the Parallax LCD screen is very easy to use and I've also used their ultrasonic and IR sensors with my Arduinos.
Since the Stamp system doesn't have the same programming structure as Arduino, I might not be able to help with programming issues, but I'm sure someone else can do so easily enough.
It looks like this  http://www.futurlec.com.au/ET-Easy328_Controller.jsp  is fully software-compatible with standard Arduino, but has different hardware layout so the Arduino-standard shields won't stack onto it. It has the same Atmel ATMega328 chip as the OSEPP Uno that I used in the magnetic levitator. But it doesn't have a built in USB interface, only serial! You need the other thing http://www.futurlec.com.au/RS232_Converter.jsp and a cable to use with USB from your computer.
Grr.
If I was buying from an Australian supplier, I might consider the Freetronics Eleven:
http://www.freetronics.com/products/eleven
Comes with the socketed processor instead of the smd version, and has room on the board for some prototyping components, as well as being hardware-compatible with Arduino shields. And it has built in USB interface, and some other nice features better than a simple standard Uno.

Any of the microcontroller systems will be able to do what you need; many people just use the microcontroller chip itself and build up their own peripheral circuitry like power supplies, output buffers etc. but that's too complicated for me. I think Stamp might be best for built-in, dedicated systems, and Arduino best for all-purpose knocking about, with ease of connection being a priority (you can just stick wires into the dip sockets) and fast changeover to other roles.


@Hoppy: Thanks for watching, and yep, it's amazing how folks like Bedini and Friedrich and folks like that are so good at avoiding tests that could show a cost of power generation in their systems.

[TinselKoala]

I had a free afternoon so I decided to start working on an Arduino pulse motor controller, even though I don't have any spare Hall sensors or pulse motors, for that matter.

I do have an IR photodetector/illuminator pair that takes 5 v in and puts out a pulse, just like the Allegro A3144 Hall sensor, though, so the sketch I'm writing will work with the Hall sensor just like it does with the IR sensor.

The sketch isn't complete, I just have the sensor read portion done. It detects the edges of the sensor output pulse, and determines the length of time in microseconds that the pulse is on, the length of time the pulse was off since the last pulse, and computes the duty cycle, on a per-pulse basis, and displays these timings on the serial monitor.

Later on I'll implement the potentiometer setting of the delay and the duration of an output pulse to a transistor coil driver.

Here's the program sketch so far, for your amusement and tinkering:
http://www.mediafire.com/?fbwun5jbndbec4b

And I'm processing and uploading a little video of it in operation so far... not very exciting but it does show the concept and the serial monitor output.
It will be viewable in a few minutes.
http://youtu.be/tDGqsz-IK28

[Farmhand]

I rewound one of the coils for the little generator but it only produces 4.5 volts RMS and it needs to be spun faster, but I can see the concept can work and that my pulse motor can easily spin it up, I think I'll go ahead and modify the bigger one with more care, compared to the little one it's about four times as big and has appropriate wire on it already, 400 mH worth of about 0.5 mm wire, that should be able to load down the motor or snap the belt. 

I just thought i would share a short clip to show the concept, the part of the core with the coil former on it comes out, and if you have several the same they can be wound differently and be changed around, the original coils for the little ones have hundreds of Ohms resistance but the bigger ones have a lot less.

The pulleys are 1:1.2 ratio up from motor to generator, I have a small pulley but I'm worried it might break the belt.

It's also a bit close to the rotor.

http://www.youtube.com/watch?v=rjKFkpm2ADc

Cheers

[Farmhand]

Hi Tinsel, Micro's are awesome when you know how to program them. I've got the software and I'll order an Eleven board they look like good value, I could drive to Jaycar town and get a kit from Freetronics, which includes a lot of other stuff as well for not much more money which would mean no waiting, I've got quite a few different IC's and Transistors, mosfet drivers already but not any of the actual parts in the kit, I'll need to ring them to find out if they have the kit in stock, apparently the warehouse is out of stock concerning that kit.

I could use the picaxe but I would need to learn how to write the hardware interrupt code. I am capable but it's difficult when I have no previous experience with programming micro's. I'm certain doing these projects will help me to learn a lot more quickly (less time wasting), I like steep learning curves, it means I get to be a bit obsessive. 

I like to use the RPR-220 photo reflector when experimenting because I can stop the motor after I find the right timing and see the reflective strip and where it triggers the reflector with relation to the magnets, I can line it up by eye because I made the angle of the light to reflective strip and back in the radial plane (no need to have the scope on except to make sure the signals are clean, the emitter and receptor are in the one part.

However I think halls are a more practical and reliable method because of dirt, dust or oil ect. I made a module circuit so as to adjust the sensitivity which is very helpful for getting a proper clean signal with optical triggers.

Double or multiple pulsing is useful for getting the rotor up to speed quicker without needing to go too long with the duty on start up. I made a small mistake on my CD4047 signal processing circuit, the retrigger pin needs to be switched between the rails I have it switched between ground and the input signal, small change, but anyway it retriggers to get going up to a few hundred rpm then it's all single pulses.

To all/anyone, with the little generator design, what would be the difference between cutting the shading bars of the core and not after I have separated the "field" poles into two side's ? And should I stick with two large  rotor poles one on each side so just one north and one south ? If for example both a north and a south magnet are engaging the same side/pole of the field for a moment will that waste power ? For example could I make the rotor with 4 x N-S-N-S poles ? With a wound rotor there is only one north and one south on the rotor but they are big and the magnetic effect of the inactive rotor coil is a lot less, nothing I guess, so I am thinking I need to keep only two rotor poles but big ones, like a quarter of the rotor face or more on each side.

Cheers 

[fritz]

I could use the picaxe but I would need to learn how to write the hardware interrupt code. I am capable but it's difficult when I have no previous experience with programming micro's. I'm certain doing these projects will help me to learn a lot more quickly (less time wasting), I like steep learning curves, it means I get to be a bit obsessive. 

Hi !

I would suggest AVR or ARM based boards with arduino as good starting point.
And if you need more performance than arduino environment - I did very crazy things with AVR controllers - feel free to ask.
(tiny)AVR 8PIN devices are even cheaper than 555, can run standalone......

rgds.