Understanding the Orbo principle by JL Naudin
created on december 27, 2009 - JLN Labs - updated on february 13, 2010
Toutes les informations et schémas sont publiés gratuitement ( freeware ) et sont destinés à un usage personnel et non commercial
All informations and diagrams are published freely (freeware) and are intended for a private use and a non commercial use.

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You will find below 3 very simple experiments which can help you to understand the hidden principles of the Orbo motor from Steorn. The experiments proposed here and their explanations are only based on my personnal interpretation only of the Orbo working principle presented to the public through videos and photos by Sean McCarthy in Dublin and may be differ from the official Steorn explanations. These experiments presented here are the tests results of all my researches about the Orbo device from Steorn.

These experiments are very simple to do and you can check these facts by yourself with few equipement. So, these key experiments are intend to demonstrate the main effect in the Orbo device which can produce free energy from moving magnets.

To conduct these experiments, you need these parts:

The 1st plastic box is used to install the moving magnets which will be used to simulate the rotor magnet. The neodymium magnets are installed as shown in the photo below :

A 3 mm foam spacer has been added so as to set an air gap between the boxes.

The 2nd plastic box is used to simulate the toroïdal stator coil of the Orbo. The coil has been installed in the box as shown below :

Two sheets of carbon have been fixed on the sides of the box to maintain the alignement with the moving magnet box.

The final setup is shown below :


There is a 8 mm air gap between the magnets and the toroïdal coil.

The measured coil Rdc is 1.1O ohms.

1 - First key experiment : Demonstrating the inductance changing effect

One of the key point of the Orbo principle is the change of the inductance of the toroïdal stator coil while the magnets approach it. To conduct this experiment, you need only to connect an inductancemeter to the output of the coil.

Without the magnets the measured inductance is 236 mH. This will be named the REF position.

When the magnets box is placed on the side of the stator box, the measured inductance drops to 179 mH.
This will be named the TDC position (Top Dead Center).

This very simple experiment demonstrates that there is an inductance change effect when the magnets box is at the TDC position. It is very important to recall that the toroïdal stator coil must be very precisely aligned between the two magnets, if this is not the case the following experiments won't work correctly.

The first Orbo effect has been demonstrated with this 1st experiment.

2 - Second key experiment : Demonstrating that the magnetic attration force is canceled by the pulse.

This experiment is very simple, you need to hold the stator box vertically while the magnets box hangs magnetically under the stator box. You may notice that the magnets box is attracted by the ferromagnetic material of the toroïdal coil due to the magnetic energy. This is here a FREE ENERGY MAGNETIC FORCE, you don't need to power the coil to attract the magnets.

Now, if you power the coil at about 6 Volts DC, the magnetic force attraction vanishes and the magnets box drops to the ground...

This is an important key experiment here to understand the Orbo working principle: Contrary to a common motor, in the case of the Orbo motor, when you apply current to the stator coil, it is only to release the magnet AFTER it has produced FREE MECHANICAL WORK !!! Think about this...

The second Orbo effect has been demonstrated with this experiment.

3 - Third key experiment : NO EXTRA POWER is needed to release the magnet from the TDC position to the REF position

Here, a bit more complicated experiment, but this is one of the most important experiment about the Orbo principle.

A function generator is connected on the optocoupler input of my Steorn Orbo v4.1 driver. The function generator has been programmed so as to send the same shape of pulse sent by the motor at full speed. Below you will find the diagram.

Look at the video of the test below, you will notice that the alignment of the stator coil with the middle line of the magnets is very critical at the "TDC position".

The voltage and the current have been measured across the coil with a digital oscilloscope at the REF position (no magnets) and at the TDC position (with the magnets).

Below you will find the results.

Below, the current curve at the REF position (white curve) has been memorised and superposed to the current curve (yellow curve) at the TDC position. You may notice that the two current curves are identical...

The Power (V*I) has been computed for the two positions ( TDC and REF ) and you may notice that the power curves are also identical...

You may also notice the fast rise of the current and then its horizontal shape.

The third Orbo effect has been demonstrated with this experiment.


A precisely machined device and a very fine alignement of the toroïdal coils is the key of the success...

To summarize

It is very important that the toroïdal stator coils must be perfectly aligned with the middle point between the two magnets :

These KEY EXPERIMENTS about the Orbo motor principle presented here demonstrate fully that :

Importants tips for the best tuning :

Don't forget that the free mechanical power produced by the magnetic attraction of the magnets towards the ferromagnetic core has no link with the electrical power spent to release the magnets.

You will find below, the full video of these KEY EXPERIMENTS

Interesting document to read:

Comments from Jean-Louis Naudin: Why this patent, below, is interesting for the Orbo motor ?

The patent below is very interesting because it says that in a common toroidal coil, each layer is equal to a "one turn coil" whose axis is parallel to the axis of the toroid. So, one layer of toroidal coil is equal to a flat coil of one turn and thus it can tap or produce EMF outside the torus. So, to counter this interference effect, the only thing to do is , for each layer of the toroidal coil, to wound a one turn flat coil along the circumference of the toroid so as to produce a magnetic field which nullify the virtual one turn coil created by each layer of the toroidal coil... This is very simple and a very important thing to do for canceling the weak CEMF induced in the toroid by the motion of the magnet and this is one of the most important key of the Orbo motor... 

Patent number: US5565835 (click on the picture to read the patent )


Inventor: Lawrence R. Groehl
Assignee: The United States of America as represented by the Secretary of the Army, Washington, D.C.
Appl. No.: 260,151
Filed: Jun. 13,1994

Main and supplemental windings are combined in a toroidal inductor to subntially nullify Lorentz Forces on the main winding and the magnetic field thereof which passes externally from the inductor.


Use of inductors or coils is well know as for storing electrical energy. As the electromagnetic parameters of inductors increase however, severe problems are encountered therewith, for example in power distribution systems of electric utilities. Because of Lorentz Forces which result from the interaction of currents with magnetic fields, structural integrity becomes a primary consideration. Magnetic fields which radiate externally from many inductors are also an important consideration because energy losses result therefrom, and a hazard to life and equipment.

Email : JNaudin509@aol.com

I am not affiliated with Steorn Ltd. Orbo is trademarked by Steorn

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