Close
0%
0%

EMDrive/satellite

Developing a small fuelless microwave thruster

Similar projects worth following
The EMdrive is a new type of thruster - recently invented by Roger Shawyer & Guido Fetta.
Unlike other propulsion systems which need to repel mass to produce thrust, the EMdrive can convert electrical energy into thrust directly.

There are endless uses for an EMDrive - in terrestric and in space applications.

A working EMdrive would start a revolution in spaceflight, enabling manned deep space exploration.

Several builds have been made worldwide (eg Chinese University, NASA), many show positive results. This topic is still quite new and needs a lot of research.

Most EMdrive builds work with frequencies around 2.4 GHz because a high power RF source for them can be made out of a microwave oven magnetron.
My attempt is is to build one which works with 24GHz, which reduces the form factor significantly and makes it possible to be used in small satellites.
A so small EMdrive could be flown to space for 20000$ on a pocketqube satellite.

OVERVIEW

-------------------------------------------------------------------------------------------

The EMdrive is derived from a closed cylindrical microwave waveguide. The main difference is that one end is larger than the other. When RF is fed into the cavity and a resonance is achieved - according to Shawyer a thrust force will occur.

---

The first builds have not been summarized due to documentation cleanup process

---

EMDrive V3

===============================================

The V3 is a silver cavity build, fed by a fully controllable RF source capable of beeing tuned between 22 and 26 GHz.

The reflected power can be measured in amplitude and phase.

First measurements with acoustic vibrations (by OOK modulation of the RF source) show a force near the designed target resonance frequency. The last experiment is reproducible and shows clear signals. Further tests must be performed to check for directivity of the force.

PS: Many many thanx to all the people who gave us very helpful hints how to improve the system. It has been an exciting ride for us until now, and we hope to provide a functional Baby-EMdrive soon

Special thanx go to TheTravellerEMD, Marvin Macportain, Keegan Reilly, Aurelio Chargb Ramos

EMDrive V4

===============================================

This build was a complete integrated version which has been tested at the TU Dresden with Prof. Tajmar.

It should have been the flight version for our satellite in case the test would heve been more successful.

We had thermal issues during testing, with temperatures of the amplifier rising up to 90°C.

This led to a massive power derating in the amp.

We had to reduce power to keep the temperature low, so the final force was only slightly above the scale´s resolution.

Other effect like lorentz forces and thermal deformation had a significant pattern in the measure plot.
Tests have been made for 0°, 180° and 90°
Results are not for publilcation yet - we will perform further tests with version 5.

EMDrive V5

===============================================

This is a development unit - derived from the V4 - which is intended to be tested at TU Dresden. It has some improvements to solve the problems that we had during testing of the V4.

It has an amplifier with better efficiency and is well thermally coupled to the casing for better heat management.

The new silver cavity geometry has an improved shape based on a proposal in Shawyer´s actual patent paper.

This shape will ensure that the pathlengths of the reflected waves on the longitudinal axis of the cavity is always kept to a multiple of lambda/2 of the resonance frequency.

  • New kind of thruster in development

    Paul Kocyla07/19/2017 at 20:34 1 comment

    Just a quick update after a long time:

    The Dresden University will probably continue measurements on the BabyEMDrive thruster with an improved torsion scale. It can resolve 20nN.

    Please check out another promising technology for propellantless propulsion. I decided to share the development and tests on a Mach Effect Thruster:

    https://hackaday.io/project/26013-mach-effect-thruster-xperiments

  • Tests

    Paul Kocyla03/23/2017 at 21:20 1 comment

    In February the EMDrive V6 has been under test on the Technical University Dresden.

    As the pretest-board didn´t output the expected power, I made a quick redesign right before the test date.
    The output after a day in vacuum was around 500mW, that´s "only" 3dB less than the desired 1000mW. Not so bad for a simple 4-Layer board.
    Here is the board inside the scale box:
    I am not allowed to publish detailed results, but some information upfront:

    The thermal drift was much bigger than the possible thrust - anyway the force is depending on the frequency and seems - I say seems because that´ s only a quick observation - to be proportional to the amplitude of the resonance peaks.
    I was only able to spend two days in Dresden so the following long duration tests has been made without my presence.
    Possible forces are lower than 0.1µN, it´s still not 100% to say without eliminating the thermal drift, so we have to wait until this problem is solved.
    The thermal drift shows always in the same direction and disturbs the interesting signal into uncertainty. So thrust is not confirmed but also not busted yet.
    From my side - the Baby EMDrive is completed, unless an affordable amplifier with a significantly higher power appears.
    There is an IAC abstract from Prof. Tajmar submitted about this EMDrive with details available on the conference beeing held in September this year in Australia.
    Thanx to the many interesting discussions and suggestions.
    Special thanx go to Prof. Tajmar, Matthias Koessling and Marcel Weikert for making the measurements possible, and Dave, who boosted the project by financial help - hope we get some thrust out of it so we can send it to space.

  • Pre-Test smulations

    Paul Kocyla02/05/2017 at 16:18 1 comment

    Jamie (monomorphic) ran a simulation on the new EMDrive V5 cavity model. Great work and many thanx!
    He detected two modes - would correspond with my two resonance peaks on the real thing.

    Kein automatischer Alternativtext verfügbar.

    Kein automatischer Alternativtext verfügbar.

  • New board ready for testing

    Paul Kocyla02/02/2017 at 22:42 3 comments

    The last board showed some power leak. The expected power could not be reached. It even degraded to 40mW - bad. Now I made a new board with better connectors and more careful routing which is ready for testing in Dresden.

    It is prepared for the highly sensitive scale and can deliver more than 200mW with 24GHz at 85°C (after cable- and connector lossed), so we should not get thermal issues this time. The ALU-Plate will be also fixed to the scale for better heat dissipation.The cavity is new (blogged about it before). It shows two clean resonance peaks at which we will test for thrust.
    Sweeps will also be made in case there are some other phenomena which may occur beside the two resonance frequencies.
    For an eventual integration into a satellite, the board can find and track the resonance peaks automatically.

    I´ll make a 360° video of the test preparation in Dresden (if allowed).

  • Measurement followup

    Paul Kocyla01/06/2017 at 06:07 1 comment

    Improvement in cavity resonance after simplifying the feed antenna:

    In the previous measurements I soldered a stub to the feed connector to reach lambda/4.
    In this configuration, this stub is missing. The feed pin is shorter than lambda/4 and its angle is the angle of the cone wall.
    There are only two peaks now, the first was also visible before, the second has a more narrow bandwidth and higher amplitude.

    Probably these peaks represent two different cavity excitement modes in this frequency range.

    We will track both of them in the next test session.

  • Cavity V5 measurements

    Paul Kocyla01/03/2017 at 21:19 5 comments

    Here is the setup:

    The EMDdrive V5 board is connected to the cavity´s feed antenna (lambda/4 stub).

    A shorted antenna is used as feedback port which is connected to a power sensor.

    First, I measured the amplifier´s performance by connecting it directly to the power sensor.
    Here are the results:

    At over 23.5 GHz the power is over 100mW - hmmmm it´s a 1000mW amplifier, so that´s not that good, the board is probably not perfectly designed, cables and connectors have losses. The sensor has a 20dB attenuator (compensated calculations for that) and a SMP to 2.92mm adapter, they will probably also cause some losses. So let´s say it´s around 150mW at the working frequency range.

    Now comes the interesting part: The feedback port is connected to the sensor, and frequency sweeps are performed. It´s basically a scalar network analysis.
    First, I left the cavity opened - this means the big endplate was not connected.
    Here is the result - flat, almost no feedback. That´s not surprising, should be like this:

    Look what happens when the big endplate is attached:

    We get three main peaks. Two strong and one weak - and some smaller artefacts.

    I assume the small disturbances are caused by the antennae destroying the optimal shape of the cavity.

    When you look at the power level, it seems that the feedback antenna is sucking all the power out off the cavity, not good, it was probably too long - but better starting off too long than too short. So I cut the feedback antenna shorter, from around 1.7 mm to 1mm (approximately). Here´s the result:

    That´s better. The feedback antenna now sucks 40mW instead of 100mW. That´s better, but still too much.

    Now I cut the antenna to the ground, it´s just a pin in the hole, but the result seems ok:

    Note that the V/div is now 20.0mV instead of 200mV, so it´s sucking just 10mW now.

    Probably some room for improvement here - let´s see, but that´s acceptable.

    BTW before the trolls cry again because of missing axis labels: The two last pictures have same labeling than the third last - I´m just too tired to insert them - have a newborn baby now and a full time job: X:FRQ sweep, Y: power 10mV <=> 1mW

  • EMDrive V5 and cavity prepared for testing

    Paul Kocyla01/02/2017 at 20:48 0 comments

    New EMDrive cavity and board prepared for measurements.
    A precise power sensor, cables (just assembled), adapters and attenuators are all rated for 26GHz.
    I will be able to tell soon exactly how much power the amp is delivering and will be able to measure the cavity properties and resonance condition.
    After these tests I will optimize the feed antenna for maximum power delivery. I will try dipole and loop.
    The cavity has two ports: One with the feed antenna at lambda/4 distance to the big plate and another with a short stub for feedback.

  • Equipment update

    Paul Kocyla12/22/2016 at 08:52 0 comments

    Kein automatischer Alternativtext verfügbar.

    New member in the lab family: A precision power measurement device.
    This device is capable of measung power qualitatively up to 26GHz.
    The funny thing is that although the design comes from 1975, it´ s still in use today and it still has its price. It´s the only thing you can buy to achieve the measuring precision for these frequencies which doesn´t have the price of a new familiy car - 40 years later. At the time of release it was different.
    Sensor head is the 8485a - was lucky to shot one on ebay for half the price they usually go.
    But now finally we get exact measurements for the EMDrive, which will help to optimize the overall design.
    The EMDrive itself will get its own power meter on board - in form of a small chip with less accuracy but good enough to do the job. But until then, this buddy will help to get qualitative results.

    The 26GHz equipment is quite expensive, for example a simple 2.92mm to SMP adapter costs over USD 70 - but it´s important to have the connectors and cables rated for the max. frequency, because in other cases the frequency response of the devices will have notches. Imperfections in the connectors lead to resonances and reflections inside the connectors, the connectors act like a weak cavity.

  • Cleaning up

    Paul Kocyla12/17/2016 at 18:54 0 comments

    The "Flying an EMDrive" project has been removed due to maintenance overhead.
    This doesn´t mean that the EMDrive will not fly - in fact we got a partnership which will make a launch available soon - stay tuned :)

    More details will come later - after we signed the contract

    The things changed a little bit now. We had a test session at TU Dresden with Prof. Tajmar and will establish a lasting partnership.

    The test results are not to be published yet due to an agreement, but what I can say is that the force was not high enough for a reasonable orbit test. The reasons were thermal issues in the high vacuum which caused the amplifier´s TX output power to degrade.
    I made a newdesign with a more efficient amp in an externall box which can be thermally cupled to the scale.

    Here´s the setup:

    I invested some of the funded money in a good used but affordable test equipment going up to 26GHz and will make a careful redesign for a next version V6.

    The paperwork for the satellite launch has been initiated, there´s a lot to do in 2017.

    I plan to do video blogging on the process. I am also expecting trolling as usual, so only constructive comments will be answered.

    The project page will be cleaned up as many of the first steps to get to the current state are not helpful anymore (learning fails).
    If you still need them then feel free to make a backup.

  • EMDrive V5

    Paul Kocyla11/27/2016 at 20:55 3 comments

    The EMDrive V5 board is assembled.
    The metal box can be attached to the scale body for better heat dissipation as we had heat issues during the testing in Dresden. There is also a more efficient amplifier on board which can delliver twice the power than the version V3.
    Now waiting for the new silver cavity to come.

View all 83 project logs

Enjoy this project?

Share

Discussions

jon-gehr wrote 05/10/2015 at 13:01 point

When can we expect results from this really from this very interesting project?

  Are you sure? yes | no

Paul Kocyla wrote 05/10/2015 at 18:12 point

We are a small team of three.
I think we can make it this summer.
As we are doing it part time I can´t give an exact date.

  Are you sure? yes | no

Neil Farbstein wrote 05/09/2015 at 23:51 point

The reports i read say that the parameters have been optimized.  You might not get a gain in performance if you  increaase the frqucny. 

  Are you sure? yes | no

Paul Kocyla wrote 05/10/2015 at 06:23 point

When we increase the frequency, we will also need to calculate a new cone, so it´s optimized for our new frequency.

First we will replicate the existing one as it "accidentally" is optimized for 2.45 GHz. I assume they also used a magnetron for the first tests.

  Are you sure? yes | no

Raukk wrote 05/09/2015 at 23:35 point

I think this is great, rather like myth busters to replicate the conditions and see if the results match. 

If you are able to see a result you should test other things that could cause false readings, like the engine might cause a magnetic field that could interfere with electronics? Or it could be interacting with the earths magnetic field(maybe)? I'm sure there are other ways it could create false readings.

How do you intend to test the thrust generated? From reading about it it seems that the result is still very small. 

I wish you the best of luck and hope you get it runing quickly.

  Are you sure? yes | no

Paul Kocyla wrote 05/10/2015 at 06:26 point

We will measure the thrust by torsion. The apparatus will be hanging on a rig, the wire it´s hanging on will be a coax cable which at the same time feeds the cone with microwaves.
A mirror and laser will allow us to see even the slightest torsion which implies thrust. We check it in both directions to make sure that the torsion is not caused by temperature, ionic effects or lorentz forces.
In the first place, we want to see if we can get ANY results :-D

  Are you sure? yes | no

Mars wrote 05/09/2015 at 22:14 point

Very interesting.  If this works, to duplicate it at home, all you need a magnetron, a suitable power supply (get both from a microwave oven, I suppose), and a chamber the right shape.  You don't need a vacuum.  Put it on a sensitive balance and its apparent weight should should change, if this indeed does produce thrust without pushing against anything.

 I agree, its ideal to have a theory before building something, but you don't need theory to duplicate someone else's build.  It was well known that you can drag a piece of thin wire "cat whisker" along a piece of pyrite or galena to find a suitable radio 'detector', long before anyone had any concept of diodes work.  Someone just noticed some materials 'prefer' to conduct electricity in one direction more than another.  History is full of all kinds on inventions where which the theory of how or why they work was figured out after the fact.  Only recently do we think we 'know it all' and won't try to build a device unless we understand how exactly how all the parts work.

  Are you sure? yes | no

Paul Kocyla wrote 05/10/2015 at 06:28 point

Yes. Experimenting is what it´s all about. But should the replica work, we want use the theory to calculate a cone shape for higher frequencies to make it smaller.

  Are you sure? yes | no

AlainCo wrote 05/09/2015 at 11:40 point

Good luck... second black swan for 21th century... to be confirmed.

  Are you sure? yes | no

Rollyn01 wrote 05/09/2015 at 05:57 point

If this works for you, you can just claim the money and still go to space. Cake?

  Are you sure? yes | no

Jarrett wrote 05/04/2015 at 16:48 point

I am skeptical and delighted that someone objective is taking this on. You know, assuming you are objective.

  Are you sure? yes | no

Paul Kocyla wrote 05/04/2015 at 18:29 point

I try to be. Anyway there have been so many esoterical fake projects on the web, that this one sunk in all that bullshit for about ten years - until a Chinese team built a functional device.
NASA got curious and also built one. And objective or not - it works.
So it´s worth a try for a DIY version. It´s a new technology, so the more people experiment with that the more things can be found out.

  Are you sure? yes | no

M. Bindhammer wrote 05/09/2015 at 15:55 point

How can you say that it works before you actually built and tested it and worked out a valid theory? From an engineering point I would start with the theory before I build any device. This isn't something you 'just' discovered. The design is based on an obscure theory...not the other way around.

  Are you sure? yes | no

Raukk wrote 05/09/2015 at 22:25 point

He meant that they claim it works. I applaud him for actually trying to recreate their tests to see for himself, rather than just saying it can't work. 

  Are you sure? yes | no

David wrote 05/04/2015 at 08:57 point

Great idea. I wanted to try this as well, but I have too many other projects on my plate. Good luck!

  Are you sure? yes | no

Paul Kocyla wrote 05/04/2015 at 11:59 point

Thanx. It´s really a fascinating topic, let´s see if we get some results.

  Are you sure? yes | no

Neil Farbstein wrote 05/10/2015 at 21:54 point

Imagine if your microwave oven suddenly lifted itself off your counter and flew out the window. There'd be nothing to put on your plate.

  Are you sure? yes | no

Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates