Experiments with hard light

[@athosbernabei5504]

Fun fact, light does push, or to be precise, applies radiation pressure onto reflective surfaces. Such a phenomenon would be really hard to notice with the lasers which he has access to, and even if he had stronger ones the caps would incinerate before noticing it. But this kind of technology works well in space for small payload missions. Solar sails have already been tested successfully and there are projects to push probes with lasers.

[@ledocteur7701]

for the probes it's a laser sail, essentially the same thing as a solar sail but artificially pushed, allowing for much smaller (tho more resistant) sails.

[@phonix6494]

And this phenomenon is also yoused to calibrate really sensitive force sensors

[@A_GoogIe_User]

indeed, light has no mass but it does have momentum.

[@DrWhom]

@@phonix6494 singular: phenomenon, so this phenomenon, these phenomena

[@pbjandahighfive]

@@A_GoogIe_User We actually aren't sure that light has no mass, just that some calculations appear to work with the idea that light has no mass, but there are experiments which suggest that light actually does have an incredibly tiny rest mass such that it is practically massless (but not truly massless).

[@bosstowndynamics5488]

I was not expecting a 3D environment modelled in a game engine to drive this, thought it would involve a hidden light sensor or something. Complex but very well done

[@Raytenecks]

Yeah, I was expecting a burst of air from the same hand. Quite a lot of effort here.

[@wurstelei1356]

I thought some rubber band firing servos got used... I never though that it was that complicated but I like the use of VR and Unity.

[@nafion112]

If it's worth building despite any practical use, it's worth grossly over engineering. That's where all the fun is!

[@alext6933]

I had expected some sort of hidden air blast. Nice job.

[@mcjavabelike8320]

yeah like a vortex cannon or somthing

[@TheNiteinjail]

I totally expected an airline into the tables triggered by some trickery ..solenoids work tho. the VR is a nice touch. Could have just had someone off camera trigger the air jets. Lol

[@dr_jaymz]

Same!

[@mq-r3apz291]

I really wonder when he gunna do soft robotics it's not as hard as it seems. I already started.

[@DIYtechie]

Same 😊

[@SAerror1]

You should look into setting up the slicing software to only use PVA for the support interface layers, it saves a lot of the expensive PVA filament when most of the support structure is printed with normal plastic and then switching to PVA for just the attachment points to the model

[@mr_doublebutt]

This is the way

[@ledocteur7701]

also, switching to organic supports instead of grid, it saves so much material while also being way easier to remove without the need for PVA (tho for very intricate parts like here PVA is definitely a plus.) and since the organic supports can bend around parts, even weird cavities print cleanly.

[@redwaller1]

Also a printer that doesn't move the heads up and down might be handy for time save. At first glance one would think the movement is useful for avoiding uneven extruder crashing. But realistically both extruders would still need to be level at their lowest travel point so his dual-extruder machine is doing some nonsense there.

[@kaustubhpandey3259]

Thats a good idea

[@ExcelInstructor]

first I thought its some sort of air gun underneath, but this has some intresting potential, and maybe i sound bit more Sci-Fi but still connecting VR with reality - well maybe we do live in some computer simulation lol.

[@olestampevestergaard4746]

It was immediately apparent that it wasn't the light, but a super convincing effect, I wish I could make something like that for my kids, they would go bananas 😂

[@bornach]

You should give it a go. Each step in the build is not that complicated. However I bet he spent the most time in system integration hell getting all the different components to work together. Mixing physical mechanisms with VR requires that the 3D spatial calibration be spot on

[@JimmyJames420]

skip the vr solinoids, use a air zooka instead :d much simpler. The fact he went through all this is awesome!!!! so many possibilities.

[@marcdraco2189]

Well you could use an IR laser and some IR receivers for the effect. Far easier than faffing around with all that. Might need another finger to trigger the correct code (think a TV remote or even use the guts from one that only does volume and channel. You know which button triggers which mechanism. We experimented with something like this when Half-Life Alyx came out but the magnetic levitation proved a bit fiddly and the range is poor. However... super-magnets repel against another magnetic field. Imagine winding a decent sized electro magnet on something like a nail to focus it and shoot a short, high current bolt through it using a FET. I haven't fully executed this but it would be a shedload easier to hide from the kids. Those "roadside rechargable" LiOn batteries pack quite a punch and would easily deliver several amps to a custom-wound magnet which you can build into the table. I might have to try this since I've got a load of wire as part of a switched mode PSU I've stupidly decided to design.

[@jackmino729]

1:40 You are correct that Photons do not have mass. However because of physics buggery they do have a measurable momentum and can apply force to things

[@Kargoneth]

True.

[@Kitsu_Worm]

I have question. in theory. if the object (in this case. light) doesn't have mass. aka value of 0. doesn't mean it shouldn't have momentum according to equation of Momentum = m * v. or are there other thing to consider that I don't know?

[@Kargoneth]

@@Kitsu_Worm See: radiation pressure.

[@isodoublet]

@@Kitsu_Worm That equation only works in nonrelativistic physics. In relativity, for massive objects the correct equation for the momentum p is p = gamma * m * v where gamma is 1 / sqrt(1 - v² /c²). For massless objects like photons, not even this equation applies, but there is a generalization which works for everything: E² = (mc²)² + (pc)². If m = 0, this reduces to E = pc, which is the right relation for photons.

[@theoverlord3839]

You can push objects with a laser-up to nearly the speed of light in fact, however it is a miniscule amount of force and negligible in an environment with much of any friction. Not to mention moving a cup in earths air and friction with ground would require a laser powerful enough that it would both melt the laser, cup, and ionize the air in such a manner that it would explode around you.

[@curtis1397]

As a Unity developer this is the cleverest application of Unity and VR I have seen. Operating physical things from within a game is pretty neat.

[@GianmarioScotti]

Photons don''t have mass but they do have momentum, so they DO push stuff around, ever so slightly.

[@Volt64bolt]

Momentum is mass x velocity, force is mass x acceleration. Momentum needs mass. They push reflective objects due to weak radiation pressure

[@massimocole9689]

The more precise relativistic definition of momentum doesn't require mass, just energy. Mass and energy are equivalent in relativity, hence the famous e=mc^2. Radiation pressure only exists because photons have momentum, otherwise that would break conservation of momentum.

[@marcdraco2189]

@@massimocole9689 I think my brain just squeezed out of my ears a little.

[@massimocole9689]

@@kenjifugimoto Yes, we already do. People can use lasers to hold microscopic objects like cells in place when they are examining them, that's called optical tweezers. Solar sails also use this principle, they are really thin metal sails that bounce sunlight off them for thrust, NASA's deployed a couple test ones and they work as expected, which is very weakly. Still potentially useful for slow probe missions to the inner solar system though. And you can increase their thrust by shining a laser on them, though getting high thrust is very power intensive. Each newton of thrust requires 300 megawatts of power. There is a plan called Breakthrough Starshot to send a tiny gram sized probe to the closest star at 20% the speed of light by using a solar sail hit with a multi gigawatt laser, though there are still a lot of technical difficulties to get it working, like finding a material to make the sail out of that wouldn't melt, and getting data back.

[@massimocole9689]

@@kenjifugimoto Atomic Rockets and ToughSF are some great websites to read about space stuff. They have some cool articles about proposed laser sail missions in real life and in fiction if you want to read more about them.

[@DFPercush]

I was expecting a vortex cannon, but this is just so much more deliciously Rube Goldberg-esque.

[@davynolan182]

Lasers do produce a force on objects, it’s true that photons have no mass but this is an incomplete understanding, photons do have a small amount of momentum and momentum can be transferred. The force is small but lasers do indeed transmit a force on objects they strike that is measurable with fairly basic equipment. You can test this with some styrofoam in some water and a moderately powered laser.

[@FaffyWaffles]

You CAN actually apply force with a laser though... In physics, momentum is defined as the product of mass and velocity of an object. According to the law of conservation of momentum, any change in momentum must be accompanied by an equal and opposite change in momentum elsewhere in the system. Light, although massless, carries momentum. When light is absorbed or reflected, it can transfer some of this momentum to the object it interacts with, thus exerting a force on it. This principle is the basis for optical trapping methods like "optical tweezers," which can trap and manipulate microscopic particles using laser beams. It's also the principle behind solar sails, where light from the Sun is used to propel a spacecraft by transferring momentum to its reflective sail.

[@jtjames79]

You are technically correct. So where can we download the build files for your version?

[@Pgr-pt5ep]

I'm sure he knows that.....but even if he didn't for most non-ultra-scientific, hobbyist purposes, he is much more correct.

[@nocare]

@@Pgr-pt5ep He might know that, but plenty of people don't and even if he did. The reason plenty of people don't is because they get treated like the nuance is too complicated for them. He didn't even have to explain how momentum transfer of light works he just had to use language like, under these circumstances I could never get a laser powerful enough to push the cups over. Instead of saying they cannot do it. Reduces the spread of misinformation and for the subset of people who would be interested by that new unknown could go look it up.

[@DrWhom]

what's the Compton wavelength of a plastic cup?

[@isodoublet]

@@Pgr-pt5ep ".but even if he didn't for most non-ultra-scientific, hobbyist purposes, he is much more correct." Eh, no. He could have said light applies negligible force, but he didn't. He said it applies no force, and justified it by saying light has no mass. That justification, that argument, is incorrect, regardless of how well it seems to work in practice. It's important not only to be right, but to be right for the right reasons.

[@donkriegnaszojcze]

This is actually way more clever than I expected! Really cool, well done.

[@vetro2689]

Exciting twist. And I would love to see more of this kind of VR/real world action

[@alexandergmzx]

This is the most interesting ad I have ever seen, great work! Even with some VR, that was not expected but excellently performed

[@chrisprobert6]

Interesting that the first advert in the video,was for two crap pointers😂

[@ProximitySound]

This would be killer tech for an escape room or other immersive experience. Amazing work.

[@3ATIVE]

Indeed, Light has no Mass but... It does have Momentum and will exert a radiation pressure force. A consequence of relativity which can be described as: P = E/c, where E is the energy of the photon. 😎

[@NiksSofa]

I was going to write that this is completely overengineered, but actually its exactly right engineered. Very cool R -> VR -> R bridge system. You could probably sell that.

[@MatchaMakesThings]

I was legitimately ready to learn how you were going to push with light. Then i became certain you were shooting air bursts, then the explanation came, and dang really good job James. Great sponsor video i'll have to try out the game.

[@soviut303]

I could see a more compact version of this being really useful for live stage shows or haunted houses, allowing the actors to cue their own effects at a distance, and in any order, rather than having to sync timing with the back of house.

[@ET_AYY_LMAO]

Next time you do solluble support, just make the interface layers solluble and you save a lot of that expensive PVa filament.

[@ilikenothingtoo]

Modbot did a video using petg supports for PLA, came off super clean. No soaking necessary.

[@ConnorHolland]

The VR control is very interesting. Imagine the system tracking your hand movement and gestures, to let you point at appliances/lights to turn them on

[@criticalposts3143]

With a system like the Meta/Oculus Quest models, you actually have pretty good hand tracking built in. You could also just use a LeapMotion controller, so I'd say this is imminently possible

[@criticalposts3143]

A disadvantage would be only being able to track at points seen by the IR sensor apparatus in either case.

[@conorstewart2214]

If you look at solar sails and optical tweezers you will see that photons can push things and exert forces, same with the photoelectric effect when photons knock electrons out of a material. Photons have no mass but they do have momentum and do exert force when colliding with objects, the force is just very small.

[@minecrafter0505]

You can use ARCore and an Android Smartphone (or ARKit with an iPhone, both have Unity plugins) and film both the real and virtual world. Just get a virtual camera attached to the position of the Smartphone (which you can sync to the virtual coordinate system through Augmented Images or QRCodes) and voilà, you can grab the camera image from the phone and the virtual image from the virtual camera and have both worlds if their positions remain in sync. Do whatever you need with that information ;) I had a research project around synchronization of coordinate spaces between AR/VR devices, happy to supply the paper (although I'd probably have to translate it).

[@davidjennings2179]

I saw the middle one was jumping up but i thought you'd done something where you were detecting the intensity of light passing through the cup and had set a threshold such that it went off only when the laser light was on it, perhaps even just looking for the particular wavelength of the laser. The VR stuff was an interesting take.

[@raegun]

Okay, that you got such an organic looking shape in CAD is...well done.

[@jamesbruton]

Loft loft revolve

Photons have no mass, but they have *momentum* , so they *can* apply force. That's how light sail works. But the momentum of photon is so low, that even with high intensity near UV light the momentum change (and thus force) is very, very small.

[@JamesBrophy]

The reveal of the trick was excellent. Next stop force push!

[@whatthefunction9140]

Photons have energy and energy has an equality to mass

[@akaegotist]

Nice touch on the magician-esc addition to the project

[@FaffyWaffles]

You CAN actually apply force with a laser though...

[@LanceCSTCuddy]

Through ablation, turning the object into the fuel that pushes itself away from the laser. Totally metal.

[@garytill]

​@Amlonde photon pressure is a measurable force on its own, no ablation or combustion required... you just need a lot more photons than we can realistically generate to do anything particularly energetic with it. Solar sails work on this principle.

[@NeroDefogger]

yes but you will need a star's power to knock a plastic cup

[@mikeissweet]

Down vote this garbage advertisement of a video. Was a complete lie

[@McCaffeteria]

This video was disapointing because laser particle levitation *is* real, but that isn't what you are doing. Clickbate.

[@pw.70]

I actually felt disappointed there! I thought there was going to be some real indepth science about crossing lazer beams and heating pockets of air and .... Nope! Still - good project.

[@kaustubhpandey3259]

Easily one of the coolest videos I ever watched

[@Omegapork]

Finally, someone who can make me the Aperture Science Hard Light Bridge of my dreams!

[@ProjectCambrian]

I Love this!! Before I started working on my Fan Film story, it Began as a humble Shooting Gallery, where I would set it up at a Convention and have Guests pay a few bucks for Charity, through the 501st Legion, to shoot Nerf darts at a collection of Stormtrooper action figures at 3.75 inch, 6 inch and 12 inch figures on a collapsible Imperial Base diorama. This was a few years ago now and at one point I thought of a Laser Tag version of the Shooting Gallery with the same kind of set up as used here in this video. That way there could be a Points Value per target assigned and other record gags, even Rankings could be set up, all for fun as a "Stormtrooper Enlistment Test" gag. Themed prizes out of small prizes, like keychain fobs, pens, stickers, anything "giveaway merch", that sort of thing. But I have Neither the equipment, knowledge or skills, well as yet, to make use of this idea and yet...I'm saving this to my fan film Resources playlist as the Solenoid triggers have Several Practical Applications I can make use of, Plausibly, in my fan film. For instance, one of my protagonists is running from enemy blaster fire along a wall with Blaster bolts hitting the wall trailing just behind them...like you would see for a machine gun, with bullet holes spraying debris from each bullet. I wanna pull off a similar shot along a stretch of Drywall/Sheetrock, with the blaster bolt holes already cut out, line up a tube in each hole, fill with some dust and chunks, Solenoid triggers each in quick succession and Voila, blaster damage on the run. That'd be cool, but time consuming to set up just for that when Hose and a bunch of Small fireplace Bellows and people for the same gag is the operational plan at the moment. But...to Revisit and pay homage to the birth of my fan series, I'm gonna use the action figure gag for the larger battle scenes in the latter episodes.

[@pbjandahighfive]

Immortals of Aveum! The game almost no one can play as you need literally the most top of the line hardware available on the market to play it at a reasonable framerate! Wow! Also, we really don't know for sure that light is actually massless, just that it's "practically" massless. There are some pretty good reasons to believe it actually does have some (rest) mass, just that it is incredibly small such that it almost has no effect (but not actually no effect entirely).

[@nathanwn93]

Nice title. I got to learn about the science of hard light and I'm glad that I wasn't tricked into watching a video about a magic trick.

[@RuthlessMojo]

It was funny to hear you say you don’t make cosplay props when earlier in your KZbin career you made cosplay outfits. That Hulkbuster suit was epic. I must admit though you’ve come a really long way since then. But that cosplay stuff was great. It was how I was introduced to your channel.

[@ankokuraven]

reminder photons don't have mass they do have momentum they can and do apply force, just very little. In space, however, its enough to divert an objects course over time, and lights on space craft give off a small amount of thrust.

[@jayprakashbhele9442]

at first i really got intrested into the hard light thing😅

[@RiddleTime]

I have to admit, this is a very good take at an advertorial, great work!

[@recklessroges]

Excellent invention and design by James. Lousy name by EA calling a vambrace/gauntlet (something that goes on the arm) a sigil, (something that is drawn on inscribed.) It's like calling the basket on a sword calligraphy.

[@Khan-jo1zg]

So this is all a EA plug and there is no kinetic laser... Well i mean obviously there isnt what was i thinking.

[@Bigbossperson]

More creators doing these now. Hope it isn't regular

[@BobsBikingAdventures]

Phenomenal use of tech and imagination!

[@alexmipego]

Actually the laser light, any light/photon has momentum despite no rest mass. Meaning that the laser was in fact pushing the cups. I've seen videos of people using big/light levers to demonstrate/measure this.

[@jupitersky]

That was a wild way to so the magic! Very cool!

[@RealAndySkibba]

Super cool application of magic/misdirection.

[@truetech4158]

I built a folding tv dinner table like yours with a larger than standard size platform board. Normally those are a smaller tabletop. I put stoppers at two heights, coffee table, and dinner table height. You could use the lasers to activate a explosive or combustable, but a magnetic railgun makes more sense. The lasers can be used to triangulate a field that could collapse signals and electronics of potential targets PWM regulation.

[@yootoob7048]

3:55 "Now I really don't make cosplay props . . " says the man who built Iron Man, a Transformer and Elmo.

[@PotatoClips]

James, a big resin printer is relatively inexpensive these days and could help out with fine detail parts. They have different learning curve than FDM but it's not too bad if you keep things clean and ventilated.

[@Mulakulu]

Nit-pick. Even though photons don't have mass, they are able to exert a very small force onto objects they collide with. This is a measurable force, and veretasium made a video about it

[@omegaroguelp]

Red Dwarf?

[@fallingwater]

This game is being pushed so hard by so many youtubers it automatically makes me want to not play it

[@jamesbruton]

ok

[@DrWhom]

@@jamesbruton honestly, man, that game is crap

[@StormBurnX]

I kind of just assumed he was shooting rubberbands from his fingers and using the lasers to aim haha. This whole setup is a very Bruton arrangement

[@darth_dan8886]

"Any sufficiently advanced technology is indistinguishable from magic" - Arthur C. Clarke.

[@engineeredlifeform]

So it's 'Tin Can Alley' meets 'Immortals of Aveum', cool!

[@EVG_Channel]

If a photon has momentum it has mass.

[@yeroca]

Not rest mass, though.

[@EVG_Channel]

@@yeroca relativistic... but still has some pressure

[@yeroca]

@@EVG_Channel Yes, definitely.

[@Zimmon375]

A 16th century peasant would scream seeing every single component of this video

[@isodoublet]

Light has no mass, but it does have momentum. Just a tiny amount. With about 300 MW you get 1 newton of force.

[@nikkothegoblin]

Both a really good sponsor tie in and a clever solution! Did not expect the virtual space twist at all

[@noahhanson7203]

The very best thing to see right when I open youtube!

[@SeanHodgins]

That solenoid placement to knock over the cups give a really good effect. I thought it was a high power blast of air at first.

[@lukewilliams8548]

Your mixed reality projects were pretty neat

[@ElDJReturn]

Clever trickery there!

[@DerSolinski]

James you are awesome. This the best "whatever, I guess I have to promote that thing now" adverb I've seen. Probably not what EA wished for, but what they deserve. Thank you for that.

[@TehMagilla]

"Photons of light have no mass" - James Bruton, 2023

[@mothcub]

you'd better not try to push me over with this laser

[@jamesbruton]

Where would I put the solenoid?

[@Dudleymiddleton]

Soon as I saw "hard light" I reminisced to Portal 2's hard light bridges. This modern game seems too intense and typical to me because I'm an old git!

[@mrwoodandmrtin]

No wait, you mean all those space movies lied to us? Cool, project big J.

[@nateolmsted22]

I thought the wrist thing was a decent project, but seems like the magic was the real project 😅 very cool end look 👌🏼

[@zacharymesecke9638]

That is actually so creative

[@inadad8878]

I would personally like to see a 3D printed version of the SALTO robot. The 1 legged bouncing robot!

[@jac2206]

Really nice Video

[@pseudotasuki]

I designed a cooling duct for the Taz Pro which eliminates the risk of spaghetti evolving into a solid blob which encases the extruder

[@H34...]

This is actually a really cool sponsored vid.

[@kevinmcaleer28]

The Great Brutini!

[@Allan_aka_RocKITEman]

Great video, James...👍

[@guxit]

"I dont really make cosplay parts..." The whole reason I'm here is due to the giant hulkbuster suit 😂

[@benscootin4329]

Brilliant. Can this be used for Roko's basilisk?

[@Douglas_Props]

1:20 to Skip to the actual reason you clicked on the video

[@oliverdowning1543]

Stationary photons have no mass but stationary photons don't exist so...

[@Scott_C]

"I don't like cosplay props" says the man who's built a full Hulkbuster outfit. 🙃

[@ZeroInDaHouse]

Haha I think everyone was thinking of an easy trick like shooting little transparent beads from the glove. But the real solution is on the completely other side of the prank engineering spectrum.

[@DeGodOfTime]

Special effects were really cool, I heard a snap before you even moved your hand. Seemed like a nerf gun 5:43

[@Niohimself]

James dabbles in stage magic now :p

[@FusionSource]

Great video as usual. You should use Tree Support, much easier to take off and uses less filament on your 3D prints.

[@Paul-rs4gd]

This is real Technomage stuff !

[@dylandreisbach1986]

Hard light does technically exist right? Something about scientists making laser diamonds. I doubt it would be anything more than fractions of a millimeter large for fractions of a second. Also light doesn’t have mass but it does have energy. Solar sails do work to push spacecraft with light alone. Now it’s such a small amount that it only works in space with light objects and large sails. Any amount of gravity working against an object would overpower the sails.

[@DynamicEllie]

Watched some of the video, then came back to watch the rest later. Suddenly, laser light is knocking over red cups.... Confused the hell out of me for a sec.

[@dumdidumdumification]

Neat!, I thought you did it with one of those shockwave/air blow toys.

[@wolf1066]

Figured you had something underneath to knock the cups - that used to be the standard trick for bottles "shot" in old movies -

[@Bhazulle]

That was cool man.

[@partykeller1553]

1:35 - Radiation pressure has left the chatroom

[@Gainn]

'Tin Can Alley' with extra steps.

[@dxb338]

photons may not have mass but they have momentum. otherwise solar sails wouldnt work. you can push a light sail with a laser.

[@gcewing]

Light does actually exert a force on things, but it's very small. A laser powerful enough to push a cup over would probably vaporise it first.

[@rakninja]

at least in atmosphere, deep into a planet's gravity well. much more effective in space.

[@cheasify]

I know this is very pedantic but despite the fact that light does not have mass, it does have momentum so it can push on things. Solar sails use this.

[@philurbaniak1811]

👍👍 absolutely brilliant! The emerald laser pointer of the man behind the curtain 😃!