HEXASCARDIFF

The HexaScarDif is a differentially driven, screw actuated, 6DOF robot platform. It came from some discussion with Apsu ( / propter .
LISA Simpson ( • RepRap LISA Simpson - ... )
Sextupteron ( • Sextupteron Extreme (+... )
Hexapteron ( • Hexapteron - The simpl... )
HELIOS ( • RepRap HELIOS Sequenti... )
Apsu's Channel ( / propter )
5D Slicer (www.dotxcontrol.com/products/...)

[@mauriciobailey4725]

You can not believe the sheer joy and amazement I got discovering your channel today. I am an aspiring engineer and have been fancied about the kinematics used in experimental 3D printers (I have a few design ideas of my own). When Nicholas said helped design the Hexapteron I was like "Wait... YOU came up with it!? That is amazing!!". It's like meeting the author of your favorite book series or movie franchises.

[@NicholasSeward]

Awesome! I called it the Sextupteron but the paper was published with the name Hexapteron. Feel free to drop crazy ideas. They are welcome.

[@bencressman6110]

Everyone here seems to be kind of in the field/ knows what's going on. KZbin just recommended you to me and I'm a builder, I have not a hot clue what's happening here. But it's brilliant. And amazing, and beautiful. Great job, I can't imagine what pleasure seeing the prototyped 6-armed-thing working brings!

[@jgiuguigiugigiugugiuuig4050]

Hi Nicholas, so glad to see your post. All your designs have been a great inspiration for playing around with wilder kinematics. Thank you

[@FilterYT]

Awesome Nicholas, great to see another post!

[@simonmerrett]

Great walk through and exposition of the fruits and challenges of different topologies. Thank you for publishing.

[@simonmerrett]

And the title made me think it would be something to do with the Welsh capital city!

[@larditard]

It is just wild how some genius inventor hackers are out there like yourself with relatively low follower counts but super high quality content. Thanks for doing what you do - really nice work. Shared!

[@NicholasSeward]

My students are always impressed when they discover I have 3k subscribers. :-) What is cool about my subscribers is that they also have some amazing ideas. I like to think of it as an elite club. (That said...I won't object to having more subs and eventually making a little money.)

[@jacko_3434]

So cool! I love your designs, they are such a blast to look at. Greetings from Germany :)

[@captivenut4122]

Great to see a new vid from you!

[@Apsuity]

Nicely done, helps illustrate the ideas we've hacked on :)

[@Thatdavemarsh]

Doobley-doo. Great shout out there!

[@scienteer3562]

Wow. Very cool. I still read the name as Hexas Cardiff despite knowing the Scara derivation.

[@frankearl9285]

This one looks...intriguing. Much like some of the other printers you've done or attempted. Can't wait to see it attempted.

[@bdh4]

Great video. Makes me miss the days of ConceptForge and makes me want to make an updated GUS Simpson!

[@NicholasSeward]

I know. I am very tempted to build an improved Simpson. Maybe someday.

[@JohnMeacham]

Really Enjoying the extended format! I'm working on a 5D extension of my toolchanger by adding tilt to the z bed. Somewhat boring compared to this. :)

[@rainmaker3d]

Hi Nick, great article on Make Magazine! I am from Hot Springs, you really inspired me about 8 years ago and I even tried to make a Wally! Keep it up it's awesome to see a true innovator in Spa City!

[@NicholasSeward]

That is great to hear. Hit me up if you ever want to come by ASMSA and check out our space. I would love to meet like minded peeps around here.

[@rainmaker3d]

@@NicholasSeward that would be awesome! I live in Batesville now but come back to Hot Springs every month or two. Would love to see your setup! I've got a printer design for a giant MLCD printer I want to make someday and would also love to be apart of making an open source concrete 3d printer for making homes and structures with.

[@NicholasSeward]

@@rainmaker3d Perfect! Hit me up when you come to town. I also dig doing design reviews if you ever need someone to do a once over on something that you are working on. My email is [e-mail].

[@rainmaker3d]

@@NicholasSeward Awesome sent you an email thanks!

[@MakingwithLuke]

Well, I'm happy to say I'm in the minority, but only because of your and Apsu's previous designs. This video is one of your best in terms of how well the ideas are explained. This design is a really fun concept!

[@NicholasSeward]

I am curious what the understanding level is before and after my explaination. (I was pretty proud of this video. I do need to work on my camera and sound but that will come if I start doing these more often. 🤞)

[@Antoniobeta]

Great!

[@carlo8956]

Love the white board !

[@NicholasSeward]

That is my school "chalk" board. I dont erase unless I need room. Makes me look more like a made scientist.

[@expression3639]

How can lead screws create a rotation like this without the arms moving up and down?

[@Im_Ninooo]

bless you

[@rogerdueck9725]

This is awesome but I love it when you say "easy mixing"...easy...

[@wrOngplan3t]

Nice! Very interesting! But one thing I don't get is how the blue arms turn (partially) around the screws. Like at 0:19 where the "head" (center piece) is moved around the build area, as it would be if a 3D printer. It can't be just friction to the screws?

[@NicholasSeward]

I don't know if I understand fully but friction keeps this from working well. It is just a geometric conatraint...friction ends up overpowering that and making this a bad idea.

[@dmcdcm]

I understand the benefit of more degrees of freedom for milling, but what is the benefit for 3d printing? Does the angle of the nozzle change the print? Or another way to ask it, do additional degrees of freedom allow you to print something you can't with a regular 3d printer? (Off the top of my head i just thought of being able to print on the surface of an arbitrarily curved object but I'm struggling to imagine more than that.)

[@NicholasSeward]

The main benefits would be smooth top layers and no limits on overhangs.

[@abdullahcakan]

Excellent project. Any information about kinematics inverse/forward?

[@NicholasSeward]

Haha. We made the 3dof version and it was as bad as I expected. Would need almost zero friction screws with a high pitch. Even with those magic items we would need insanely rigid and light materials to handle any load at all. I haven't formally done the kinematics. I probably would go with iterative constraint solving to build a small lookup table to speed processing and to keep away from nonphysical solutions

[@dejayrezme8617]

Wow haha awesome. I'd think this might be a really easy robot to build. A small pitch would give you accuracy to rotate and position the effector. The Z axis would be the slowest, but for 3D printing that might be ok. I'm very curious why you would go for 4 DOF version. I'd think 5 DOF would be "perfect" for 3D printing.

[@NicholasSeward]

There is a project that needs 3DOF but the 4th DOF just makes it all work better. I want to keep it a suprise for now.

[@strictnonconformist7369]

Hi @Nicholas Seward, I've been following your works for several years now, and I agree, using screws to achieve straightness in this context would be problematic for costs/etc. because they'd need to be perfect or it's very wonky and hard to ever get useful results, even if you calibrated for warped screws in software (it could be done, but a nasty problem). There is another solution that would make more sense, I believe, that'd be an evolution towards Bob Simpson: this geometry is already huge and it'd cost no more space to do it: each of the 6 points use Sarrus linkages with 120 degree angle offsets to achieve straight line motion and structural stability. It'd be a fun bit of work, but I think far more viable than trying to perfectly match 6 screws, and far cheaper than 6 screws with sufficient accuracy would be. It'd be a design choice as to whether it'd be a suspended design or come up from the bottom for anchors.

[@NicholasSeward]

I am intrigued but don't visualize what you are talking about. Any chance you could sketch it up.

[@strictnonconformist7369]

@@NicholasSeward I'll try to get around to it this weekend via OpenSCAD. Let's see if you can imagine this, after first you think about a Sarrus Linkage, of which wikipedia references them with a 90 degree angle between the halves that both bend at the middle. There's no reason it must be a 90 degree angle between the 2 halves, as any other angle will also work, including 180 where it's just 4 identical length segments bending in the middle and joined on the ends via a hinge. Now, imagine 6 of them, at 120 degree angles between the halves that bend, both constrained at the top and bottom with the appropriate shape you would expect at the top and bottom: they're guaranteed to create a straight line in the motion at whichever end is unconstrained. This is where you put one of your arms. You have 6 of these around the outside of the work volume, and interleave them as needed so they don't intersect each other's path when folding/unfolding. Whether you do this from the bottom being constrained and going up, or suspend from the top and going down, doesn't change it: if you have a solid foundation for one end, the other end moves the arm with a straight motion platform to work with, sort of like 6 ballerinas doing the same sort of motion precisely, in a tight formation, with legs interleaving, assuming their knees are exactly bending at 90 degree angles (and equal length leg halves) and no flex at the waist/hips or ankles except 90 degrees, making a flower. The result: because you never want the hinges in the middle to be totally open to a full 180 degrees, you have a work volume a little short of 2 times the length of one of each of the segments, which can be the length of the side of your hexagon for vertical volume, minus the differential you need between the total height and the adjustment of the head in the 3 major directions. Does that make it easier to visualize?

[@sward8757]

@@strictnonconformist7369 It sounds beautiful but I am not quite there. I would love to see a SCAD model.

[@ekaggrat]

really cool concept. maybe it would be a working prototype. I was curious to know what happened to the helios?

[@NicholasSeward]

HELIOS is still a thing. It is high on my list of things. (Young daughter, remodeling our new house, wife in grad school, day jobs) When I get into it, I have a version I want to build that can roll up a door for super high Z prints.

[@linhphan9383]

I have a problems with kinematic of tripteron. Can u help me please

[@NicholasSeward]

Tripteron uses the standard cartesian kinematics. Nothing fancy.

[@SquishyBrained]

I LOVE your stuff. We should chat sometime soon. (ICON)

[@NicholasSeward]

Would love to. My email is [e-mail]

[@TheRainHarvester]

12:50 What program are you using?

[@NicholasSeward]

Inventor or Fusion. Specifically a 2d sketch.

[@WildInocence]

Great project, have you think to design something like a brother for HEXASCARDIFF? Wall delta printer with 6 instead of 3 axis, like -x,+x, -y,+y,-z,+z since xyz have mirror axis in inverted direction, gave more streng, more stable and delta maths, but in some way work like core xy. Hope someday you try this idea. Greetings from Portugal

[@NicholasSeward]

I dont have a mental image of what you are describing. I can see a TriScarDiff that has three parallel coplanar screws. Any way you can sketch up what you are talking about?

[@WildInocence]

@@NicholasSeward I have a stl draw, I call hummingbird, how I can send to you to see, thanks for the fast reply, so good ideias came from you. Keep the good work 😁

[@sward8757]

@@WildInocence my email is [e-mail]. I think you can also put a link in the chat.

[@WildInocence]

@@sward8757 Great thanks , sended !

[@4.094]

Love looking your progressive in the future.

[@simijuracka8293]

Hello I've got dumb question : what does scardiff means?

[@NicholasSeward]

Differentially Driven SCARA

[@simijuracka8293]

Oh thank you mister.

[@StephenMattison66]

Cool! Mesmerizing! Brilliant! You should help Elon figure out the grabbing arms for his "I'm catching the 70 meter tall 100 ton Booster right out of the air, no legs needed" launch stand. Insane but I can't wait to see him pull it off! I have a great Grabbing Mechanism design, but I can't even get him to respond on Twitter or email about my "Springblade" leg design for Starship, which needs new legs bad! Springblade is sweet & SO simple!! Love your stuff!

[@NicholasSeward]

Make a video and share it. If it is good enough, peeps will pay attention. (I know it isn't that simple but some percentage of good ideas get paid attention to.) Drop me a line when you do. I will signal boost it if I think it is good.

[@StephenMattison66]

​@@NicholasSeward Very cool, thank you! I'll find your email and send you .jpg of my SketchUp design, Springblade is very simple, easy to see how it works. When I first Tweeted it to Elon I had a bunch of people say they looked great, but that I should remove the images because someone will steal the idea and call it theirs. Not so worried, only Elon would ever need the design, he knows where to find me. I have made improvements since then, channeling my inner Elon. I do need to learn how to do animations so I can show them working, you're correct, that would be the best way to get others excited about it. If you're interested to see the CAD image I Tweeted Elon immediately, just Google "steve mattison twitter elon springblade legs." Springblade is like a giant runners prosthesis blade, but 1m wide curved titanium-nickel, if necessary several layers, like a leaf spring. The mechanism attached to the base of Starship has a eight rollers (like super strong baking rolling pins), four roller have motors and roll/shuttle the leg almost straight up under the skirt, there would be a simple friction clasp that the top of the Skirt that the leg would settle into. Springblade gives the wide stance & shock absorption that Starship will need on Moon/Mars, also holds the Ship 2m off the surface, and each leg can be lifted/adjusted to level Ship and also lift any two legs and can repair/replace/test the leg in-between. #peace2u #goelon

[@AuDHDQ]

link in the doobly doo. An AVE reference???

[@CutterSlade001]

All old school KZbinrs called it something like that back in the day.

[@NicholasSeward]

I got it from watching vlog brothers.

[@matthahne]

it was originally coined by WheezyWaiter waaayyyyy back in the day

[@Unmannedair]

So you've created an odd Stewart platform... I don't get it.

[@NicholasSeward]

haha. It isn't a practical idea but if it was workable, it would be a stewart platform that can collapse down to a thin plane.

[@__--JY-Moe--__]

nerd!! nice movement plotting!!

[@robmckennie4203]

I feel like you started out really basic by explaining what differential control is, but at some stage skipped some key information or I'm just a moron because I still have no idea how this machine works. So 20 minutes of my life wasted and now I'm frustrated

[@NicholasSeward]

No worries. This is some strange stuff. Anything I can help you with? For the record, my testing shows it is just as impractical as I expected.