Tractor Beams are mysterious waves that can attract particles towards the source. Here, we will show you how to build an Acoustic Tractor Beam with components that can be bought directly on the Internet for less than 75$.

With this Instructable you will be able to get in your hands a device that it was only seen on SciFi movies such as Star Wars or Star Trek.

If you want more scientific background on Acoustic Tractor Beams, you can check our Open Access research papers:

Do not forget to watch the attached video in this Instructables.

Step 1: Gather the parts and tools

We present a list of the necessary components. I have tried to place links for different countries. However, the same parts can be found all around the world, some useful websites are http://www.findchips.com/ http://www.dx.com/ http://www.miniinthebox.com/http://www.lightinthebox.com/http://www.banggood.com/

The circuit is not complicated. Basically, an Arduino will generate 4 half-square signals at 5Vpp 40kHz with different phases. These signals get amplified to 25Vpp by the Motor Driver and fed into the transducers. A button pad can be used to change the phases so that the particle moves up and down. A battery (7.3V) powers the Arduino and the logic part of the Motor Driver. A DC-DC Converter steps-up the 7.3V to 25V for the Motor Driver.


  • 30x 16mm Transducers MCUSD16P40B12RO (US UK) . Alternatively, you the MSO-A1640H10T but minimum order is 500, they are good so perhaps you can save them for future ultrasonic projects.

Necessary Tools:

  • 3D printer -> you can use an online service
  • Soldering Iron, Tin and Flux.

  • Drill

  • Hot-glue gun

  • Multimeter

  • Cable Peeler

  • Screwdriver and Pliers.

<p>Could the project benefit from acoustic foam behind and around the transducers to negate any sound reflections with phase change?</p><p>Also, you mentioned that this size is optimal. Does that mean a larger diameter sphere with more drivers has little to no benefit in terms of lifting ability?</p><p>Awesome project BTW and I appreciate that you have made it open design.</p>
You are right, placing foam around the transducers could reduce secondary reflections, although in this configuration it is not a big deal.<br><br>The design is optimum for 25 transducers. A larger sphere with more transducers would certainly add more power, but transducers are a little bit pricey and 25 is about the maximum that you can drive with one driver.<br><br>Glad that you like the project, thanks for your comments.
<p>I understand that the transducers are the most expensive parts in this project. Are these transducers are going to work?</p><p><a href="https://de.aliexpress.com/item/Plastic-shell-16mm-ranging-probe-ultrasonic-sensor-transceiver-T-R-avoidance-proximity-switch/1644877997.html?isOrigTitle=true&isOrig=true#extend" rel="nofollow">https://de.aliexpress.com/item/Plastic-shell-16mm-...</a></p><p>Thanks a lot!</p>
They look good, and good price also. <br><br>I am still testing some Alibaba transducers that are 0.3$ units, if they work well I will put them in the description.
<p>Are those transducers with a minimum order of 500pc?</p>
<p>Thank you so much! I'm really interested in this field, and I appreciate your willingness to share information. You are my new best friend. lol </p>
<p>Great Project. I'm going to do this for a schoo, project, could you give me some tips?</p>
Tining the tips helps to put several wires in the same hole. Get a cable peeler otherwise it is a nightmare to do the wiring. Get a cheap oscilloscope to get the polarisation of the transducers and test the signals at each point. Good luck!!
<p>Could you post the CAD files you used to generate the STL file for the bowl?</p>
I have added them in the last step (They are inventor files).
<p>I did a modified version because I had the smaller 10mm transducers already.</p><p><iframe allowfullscreen="" frameborder="0" height="281" src="//www.youtube.com/embed/nPNzMCGHVG8" width="500"></iframe></p>
<p>For those of you thinking perhaps the video is a little noisy I can assure you in real life its silent. The sound you hear comes from the microphone which is clipping due to the high pressure ultrasound.</p>
<p>I've ordered all the parts for this and plan on building one for my physics presentation this term. I had to order the transducers from aliexpress and am concerned they won't ship to me in time. </p><p>Does anyone know anywhere that has them in stock? I have all the other parts either here or on the way. I've already 3D printed the bowl at school. I'm located in the United States. </p><p>Thanks!</p>
Your configuration of the acoustic tractor beam is great!<br>Since I am not very expert in acoustic transducer could you please help me? I've found another type of transducer at a lower price. The frequency is the same but sometimes, such as the pressure on a certain distance change . As for the material is made out of plastic, but other specifications are not mentioned in the characteristic (angle beam, driving voltage). Could you please tell me in your opinion If they can work properly? Thanks in advance
They look alright, are they from Alibaba? I ordered some of those to test.
Yes they are from Alibaba.<br>Another thing, is it possible to use transducers with a lower frequency (25khz) in order to levitate bigger object or in order to mount them some modifications to the device are needed?
<p>The bowl could be the same since it is naturally focused. The code will need to change substantially: the timer1 adjusted for 25khz, the delays between OUTPUTS increased and the phases that are output changed. No worries I have plans to release more versatile boards. One easy way would be the use the code from the last steps that is much easier to change to generate 25khz.</p>
<p>Ok, thanks a lot for the informations!</p>
<p>Really Kewl!!! Love it, gonna make this :)</p>
<p>Excellent resource, thank you for publishing. We want to make one at school as a project for some yr 11, I've costed out the parts at &pound;80, but I have not allowed for the 3D printing yet. Our printer here has broken anyway so would need to get it printed elsewhere. How do I access the file for the printer?</p>
<p>Voted across the board for this. Gonna order everything I need to build it when I get paid next! How long before we see one big enough to lift large objects?!</p>
Can we use any 40khz 16mm transducer? Newark messed my order up and they are out until March now.
<p>Yeah, although usually the metallic ones do not work that well.</p>
<p>Is anybody interested in getting some transducers and building this thing? I got a quote for US$1.5/pc, but would need to order at least 100 pieces. Please note that shipping, customs and tax are not included, yet, and would be shared. I could ship them anywhere within the European Union. Please get in touch.</p>
<p>Why does the Tubes Project use so many Transducers ?</p><p>- Why not divide the power Control between the Transducers - so you can move the object ?</p>
<p>There are several transducers but they are all driven with the same signal. In the coils device it would be possible to use a single source but it is quite hard to get such a big and powerful planar source for air.</p>
<p>I think the question was lost.</p><p>Question is: Why Not split the signal into 4 or 8 instead of Dual Upper / Lower Power Signal to the Transducers ? - so you could bounce the Target around across the surface ... ?</p>
<p>The previous prototypes had a signal for each transducer, so we could move the particle anywhere and even rotate it. But we wanted to simplify the project as much as possible, so having more than 4 signals would imply another driver.</p>
<p>Wow, will you make instructions for this design?</p>
<p>Speaking of coils, could you explain me what their role is.<br>I understand they might have different lengths so the output is dephased compared to the uniform source signal. is it?</p>
<p>Exactly, all the coils start at the same height and end at the same height, but they have different lengths. So when a simple planar wave enters the coils, the sound has exactly the same phase at each coil but when it exits there is the appropriate phase at each coil. Phase &lt;=&gt; Delay &lt;=&gt; Distance.</p>
<p>Okay, thanks!!</p>
<p>Not OP, but that is how I read it in the research paper.</p>
<p>How do you change the frequency in the code?</p>
<p>Very impressive! How powerful is it? Would it be able to hold, say, a drop of water? If not, would it just be a function of getting stronger transducers to make it possible?</p><p>Awesome research! I look forward to reading the full paper. </p>
<p>This version can deal with expanded polystyrene, pieces of popcorn and Cheetos. If you crank it up to 30v, then small flies and similar insects. The problem is that tractor beams have pulling forces that are 30 time weaker than a traditional standing wave. You can make two of these devices place them face to face and feed the same signal into all the channels, that creates a standing wave that can levitate liquids. But no worries, we will keep releasing our different devices and software related to ultrasonics.</p>
<p>how about enclosing 6 coils device to make a cube? how strong will the standing wave inside the cube? </p>
<p>Quite strong, but most of the times with top and bottom is enough since your main objective is to overcome gravity.</p>
<p>instead of having all of that couldnt you just use a transducer and a couple of battery? Wouldn't that work to if it was lined up properly?</p>
<p>Huh. that REALLY makes Star Wars look unrealistic!</p>
<p>instead of having all of that couldnt you just use a transducer and a couple of battery? Wouldn't that work to if it was lined up properly?</p>
Just listened to a podcast of your Science Friday appearance. Very impressive - the Instructable, time you've taken to answer questions and your plans for the technology! Good luck. Make sure to revisit Science Friday when you have more news to share.
<p>I do not have the equipment to build this exceptional piece of technology, but the implications of this device are staggering! I have seen technology that was so much fantasy. None of it was real, and now, we can build a tractor beam at home with just a few circuits and some parts from on-line! Thank you for posting this, thanks for sharing your work! I can say that I have seen many things that were simple fiction, come to reality. However, a Tractor Beam? That's totally AWESOME!</p>
<p>Would substituting the wooden handle out for a 3d printed one cause any problems for the design? <br><br>By the way Asier, thankyou for sharing this invention with the maker community. </p>
<p>Not at all, in fact a student is designing a handle where everything sits properly. We can upload the STL later. But I prefer the wooden since it is cheaper and faster.</p>
<p>Also Azier, you have managed to beat star trek to this one!. In the earliest (in the story timeline) star trek, Enterprise (Set about 50 odd years before kirks star trek), they hadn't invented tractor beams yet, so instead they use a big grappling hook they shoot out from the bottom of the ship.</p>
<p>Would the HC-SR04 UltraSonic Sensor Transducers work if Removed ?</p><p>- I have a bunch lying around ...</p>
<p>Mmmm those metallics ones work a little bit worse than the plastic ones but they can do the job.</p>
<p>hey,</p><p>i really liked your project and i am dying to make it the transducer you mentioned in this instructable is unavailable in india. So i found another one pls check wheather this one can be used in the project instead of the one you mentioned. the link is provided below:</p><p><a href="http://www.ebay.in/itm/Transceiver-48KHZ-17-5MM-Metal-MCUSD17-5A48S11RS-30C-Multicomp-/262582678052?hash=item3d2325b224:g:Ma4AAOSwZVlXtObJ." rel="nofollow">http://www.ebay.in/itm/Transceiver-48KHZ-17-5MM-Me...</a></p><p>this is a 48 khz transever pls help me.</p>
<p>They will not work mainly because they seem designed for water, I think they are also weaker than the others, the frequency is a little bit higher and they will not fit the sockets. These ones may do the work although the metallic ones do not work as well as the plastic ones: http://www.ebay.in/itm/40KHz-Ultrasonic-Sensor-Pair-Transmitter-ZT40-Reciever-ZR40-1-Pair-/162333202789?hash=item25cbd01965:g:wc4AAOSwCGVX3PZ~</p>

About This Instructable




Bio: Researcher at Bristol University interesting in Ultrasound and in general any effects that waves can produce.
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