Compliant 6-Degree-of-Freedom Precision Motion Stage: The Hexblade Positioner 

very interesting observation.

Shuu!! Get out of here that knowledge will only be used to annoy your wife in one form or another... Greatly to my entertainment that is 🤣

hi shane :)

My dude! I have no idea what any of that means but now I'll get stuck in a Google rabbit hole figuring it out, thanks.

ah so this is why youtube recommended me this video

As someone who finished their undergrad it goes to further my self doubts as I loved matlab in college and his 3d implementation makes anything I’ve ever done seem trivial, and I don’t even know how one would begin FEA in matlab. I assume plug-ins of some kind.

Oh I’m an idiot. I was only half watching on my first watch through and now noticed he simply used solidworks for the FEA

as an undergraduate pursueing ME in my 3rd year this is the kinda stuff that makes me feel even more useless when the workload gets crazy because i could never come close to writing the matlab scrips for this

@@daneprostamo-brown6552 I loved matlab, so this did a similar thing, but remember that the purpose of masters subjects is to delve very deep into your research project. This could have been a year in the making.

@@daneprostamo-brown6552 thanks for this comment, for a bit I felt as if having smol brein exactly because of math involved. apparently this sensation is quite common here :D

How much would it cost to use this technology to build a small robot/vibrator for the female market? I'm pretty sure we could make some money with something like this. We could also train a neural network using electrodes on a few girls to find the best algorithms.

I watched a series of videos on YT where a guy made a controller similar to 3dconnexion mouse, all by himself, an advanced DIY. I'll try to find it and link it here, if not try googling it. Anyway, I really like your idea of 3d controller, I hope you will get there and enter the market with revolutionary input device and make lots of money. Oh, just now i got an idea, with all current advancements in AI, computer vision and whatnot, maybe it will be feasible to just use an empty box with 3(?) cameras that will track hand movements and translate these to inputs. Hand could be in a glove or maybe some rings or sth like that to better discern between fingers that can have different functions? Not sure if something like this isn't already in development, if I'm first and someone actually make such device please throw me some $$$ when you commercialize my idea :)

@@aeonikus1 I've seen multiple projects for a 6DOF joystick like the SpaceMouse, though the only video series that comes to mind is Space Mushroom by @shiura, which uses three dual-axis joysticks and a slider mechanism for various freedoms and constraints. Is this the one you're speaking of? I'd also be careful with using the term '3D' when talking about joysticks, it's such a loose term that doesn't mean much, and there's reason for that. There's 2-axis joysticks like what we see on nearly everything; and they can be considered '3D' for a simple reason, imagine you're at the center of a sphere, you can locate any coordinate without having a degree of freedom, rotation in this case, within the axis of depth, and this is quite literally how a camera stick within a video game works, and inversely you can navigate a sphere in two axes without additional degrees of freedom based on how a planar grid can loosely map to a sphere, which is how a movement stick within a video game works though this applies to really any kind of movement grid not just planar or spherical. Then there's 3-axis joysticks, which add a third axis to the stick in some way, typically it's just a Z-rotation under the Xr-Yr gimbal, but these see very limited uses outside of some niche applications, basically anywhere where 3DOF manipulation is needed. Then we get into 4DOF joysticks, which are typically some kind of X-Y manipulator on top of another X-Y manipulator, such as a slider or an analog pointing stick on a typical joystick, though at this point the joystick itself becomes a full-sized hand joystick due to obvious dexterity issues, where the new upper manipulator becomes the thumb's joystick. 5DOF, though rare if they even do exist, would be a combination of the two previous, a 4DOF on top of a Z rotation. Then we get into 6DOF, which are entirely different in that they read both linear and rotated movements of the manipulator in a more complex sensor setup, again due to dexterity limitations; I guess you could take the 5DOF and put a secondary Z rotation under your finger as a bi-directional form of trigger. All of these of which can be considered '3D' because of how we define what 3D is, and that's typically not in clean-cut dimensional axes but rather how we manipulate objects, of which objects are typically 3D, so it's better to define a manipulator by the degrees of freedom it has in total and further refine that by how it achieves those degrees of freedom; for example, the modern gamepad is 5DOF, but it uses two 2-axis joysticks and two triggers on a shared axis. Triggers themselves are typically only a half axis, they can be a full-axis but they're almost never logically implemented as such, probably due to the fact they only move in one direction rather than two; which is why I previously mentioned a bi-directional 'trigger,' which wouldn't be difficult to produce, it's just that nobody really makes them. There's also meaning in the term of 'joystick' modernly as an analog stick, joysticks used to be digital and there's very little implementation of such outside of arcade-like uses, but even then a joystick has to have a return to center mechanism, otherwise it's a continuous stepper which is why dial-like devices should be excluded when talking about a degree of freedom, as a DOF should be free to be manipulated rather than detented to specific steps; of which people that don't know better will probably get confused and just suggest that glorified buttons in the form of a stepped dial should be a 'solution' to adding a degree of freedom, sure our scroll wheel on our mice might work for zooming but we're also actuating that in steps rather in a continual input. At least this is true for manipulated inputs, the term 'degree of freedom' is also dependant on use; and some might argue that digital inputs can be a degree of freedom, but I don't really consider pressing a key of stepped input equal to the amount of what an analog sensor outputs is really a 'degree of freedom,' and I know someone will be pedantic enough to argue that 'it's all digital anyways, because that's how USB communicates, and analog devices use an ADC, etc.,' but that's really beyond this argument considering a stepped input is still one-bit binary whereas an ADC will typically be 8-bit if not 12 or 16, so even by that argument anlaog, whicle digital in the end, is still much more refined. Mice (trackballs included) and trackpads are in a limbo between the two, as they're essentially a vector device, but they're still not 'continuous' in the sense of what an analog sensor reads as, not to mention their physical, and often digital, boundaries. Input devices are more complicated than just calling something a '3D joystick,' it's better to use more refined terms, and to define how the input device actually reads its input.

.....Its called a waldo. They've been used for decades in animatronics.....

​@@TankR No, it's not. Waldos are also for digital puppeteering, not animatronics. Not to mention how large these devices are when, if you had any amount of reading comprehension, the discussed topic is about mouse-sized devices. But given your entirely incorrect use, and incorrect formatting, ellipses, I doubt you're literate enough to understand literally anything within this comment thread. Here's the main issue, Waldo is just a name for a range of devices, and a Waldo is purpose-built for a specific rig in digital puppetry, whether that puppet itself is digital or physical; again, none of this is on the animatronics side of a physical puppet. A great example of this is the difference between Mr. Volt's (@MrVolt) Wheatley puppet's Waldo and production Waldos such as what Henson studios is doing for their Waldo rigs; the former is purpose built for the various degrees of freedom a specific puppet needs, the latter is more open to multiple puppets but is widely used as only a head rig while alternative puppeteering rigs control the body of the puppets- and here's the thing, the vast majority of Waldos are discretely for head and neck manipulators. Whereas what is being discussed here, stemming from what the original device in the video was as I discussed literally only changing actuator to sensor, i.e. to make a driven output device into a driven input device, is a 6dof manipulator that's small enough in size to be used by a hand on a desktop; I've even mentioned the SpaceMouse and its DIYed alternatives, this should've been your second clue, right after watching the video and presumably having an understanding of the original device. And here's the next thing, how degrees of freedom are used in naming, what the SpaceMouse is, its alternatives, and what I suggested in my original comment are three linear axes and three rotational axes on the same manipulated part, whereas Waldos on the other hand are rarely considered '6dof' in this way, nor are executed as such, very similar to how robot degrees of freedom are otherwise named and calculated; you're comparing apples to oranges, hell at this point it might as well be une comparaison de pommes aux pommes de terre, if you understand French and have enough logical understanding of why it's a bad comparison via naming convention, of which I'm doubtful of you having any capabilities of logical thought, comprehension competency, or even basic understanding period. The next issue is size, Waldos are absolutely massive and complex. You might as well recreate a Novint Falcon for a 6dof manipulator at this point if you're arguing a Waldo would be of any practical use here. Again, your first clue should've been the fact that the device in the video is driven by voice coils, and you presumably understand how utterly small voice coils can get, given that a lot of IEMs (earbuds) are dynamic drivers, i.e. driven by voice coils. Again, your second clue should've been the relevant devices that have been named dropped throughout this comment thread, even if you don't know the device itself it is otherwise easily searchable; and stemming from this, even if you didn't have relevant knowledge of the named devices, you have analogous knowledge considering they're compared to a computer mouse. And no, Waldos cannot be reasonably sized down, considering they encapsulate your hand and wrist at minimum, then on top of that you also have a stable frame to keep them in place or you have a perch that sits under your forearm. Even if you could size down a Waldo to even properly fit on a desk and integrate into a peripheral ecosystem, it would again akin to be what the size of the Novint Falcon was, if not even large; and again here, I'm thinking you lack any amount of logical thought, comprehension competency, and basic understanding of things. So, what does this mean? Waldos are nonapplicable for the argument and are irrelevant to the conversation, and they cannot be made to work in a way that makes them applicable to the conversation. You lack any amount of reading comprehension competency, literacy, logical thought, the capability to research anything, and lack even the basic understanding of anything relevant to the conversation nor the basic understanding of what you're even talking about. Perhaps you should educate yourself, and until the point of being educated I would suggest that you sit down and shut up. Your reply is on-par with some of the most misguided, misinformed, and unintelligent horseshit I've read in relation to intelligent conversation. Even out of respect for intelligent conversation, and by extension respect for others' time and intelligence, you could have at least done your due diligence to understand the conversation itself, rather than spewing nonsense that is proven to be irrelevant, especially when you do not inherently understand what you yourself are talking about. You can't even have respect for basic conversation, any intelligible portions of the conversation aside, as your incorrect use of ellipses heavily implies a tone that I, or by extension the other party as well, have no idea of what we're talking about and implies a tone that you are talking down to us as if we're lesser, pauses in speech as how you executed always imply this tone, in verbal speech, in writing, and in literacy uses such as dialog in story writing; and this is a point you can't weasel your way out of. People like you act like they're so intelligent, yet are some of the most unintelligent, act as if you're so highly informed, yet are rather the least informed, then you go off on this twatty behavior such as the tonal implications of how you formatted your reply, yet you're the one that's entirely deserving of being talked down to; you should be embarrassed of yourself, I'm sure others are, so again you should sit down, shut up, educate yourself, learn some very basic life skills such as logical thought and comprehension competency, and learn some basic respect for literally anything you interact with. Given that your account has existed since 2013, that implies that you're easily in your 20s if not older, things like this should not have to be explained to you, I get it if the education system and your parents failed you as a child, but you've failed yourself in your adult life, you were likely a class clown but now you're outright just a clown that provides nothing but dogshit on a silver platter. And on an academic channel, where most people are active in intelligent conversation, no less. And on a comment that's actually speaking of the mechanism itself and having advancements elsewhere, no less. Do better, a cat pissing in sand is more sophisticated than you'll ever be.

Completely agree on the music, and the script was top-notch; even a software fool like me could follow!

had same thought too...

the deformation is likely in the elastic range so fatigue/cold work occurs less - I would guess that's the red colour in the simulation

CF composite from 3D printed molds?

A print head mounted on one of these platforms could print a line path in non-flat layers that are optimized for physical properties like resonance and flexure. It might be useful to be able to directly generate the Gcode to FDM print a (fibre reinforced?) PLA/nylon/PC positive for this platform's frame from. Perhaps simulate the FDM line structure as well as the shape. So, even more maths. If implemented in an online calculator it would need a very long progress bar and probably a PayPal button.

That is exactly what I was thinking!

I was thinking the same thing. If you just play the audio you'll be asleep before the halfway point.

Sorry I can't give it out for free or I will be hit with a copyright infringement :( If you have access to a friend at a university or company that pays journal fees though you can get it for free from them. Good luck.

yes major bummer. thought that being darpa related would make the research open, but maybe not

Often the coil side is lower mass, so you put it on the moving side to keep your frequency response up.

Yes go to my Thingiverse account. It should be in the description. If not, it is in other video descriptions

The problem the design was meant to solve is explicitly a very small fast & precise area of movement relative to the mechanism. You are asking to solve a different problem.

Given their thin rectangular cross section, each flexure is far more stiff in the direction of intended motion, and bends very easily in the case of not. If you watch the animations at the start, I hope that makes sense. You're likely talking when motion is not perfectly defined by 3 actuators at once, but I assumed the bending moment would still mostly be in line with the flexure's intended direction of bending, so it wouldn't be too disruptive (since its cross section is like 20 times as thick in one direction than the other, and it only receives a small portion of the load that's off axis in the first place. Hope that makes sense?

@@jasondean37 I get it, but yes, I am talking about the twisting induced by the movement of the other axes. The prototype appears to be open loop, and I think it would be quite hard to create an algorithm which would tell you what voltage the voice coils should have for a given position output. If the voice coils had encoders it would be nearly as difficult. Maybe if the end effector could be directly measured for position feedback it could work.

No, there are six independent actuators for the six DOFs. To understand redundancy in actuation and constraint, you can watch the first and last lectures of my compliant mechanism lecture serries.

@@TheFACTsofMechanicalDesign thank you so much for putting those up. I'm only on lecture 7. So far on the FACT complete library of parallel systems I've only found 5 degrees of freedom so I haven't gotten there yet/my brain is too tiny to even understand why 5 degrees of freedom would be necessary. But in 3d printers they only use one z stepper which is so interesting because on this project it seems like the z axis is in part the mechanism crawling on the part! So I expect that the printer has to incrementally print in the z between crawl steps which is also so beautiful. In deltas, it feels like some of the goal is to reduce the number and cost of actuators and modern printers only use 3. Of course they've got a lot of extra mass and don't get to play with linear motors this excluding the need for linear actuators and 3d tracking for to the cost. I guess use of more degrees if freedom must have something to do with decoupling the different movements and it must have more capabilities than a parallel linkage in a typical printer. Anyways, thank you so much for your response and I can't wait to finish the rest of the lectures. I'm sure it will all make sense after I finish. Thank you again so much for putting them up!

yes please!

@gasmonkey2.075 It is about using the right tool for the job. They are persevering with unsuitable hardware and compensating for it by just using more of them and this increases complexity in itself. Rather than just using a single MCU that is more suitable they now need to deal with communication between the multiple MCUs and making sure they all work as expected. Using a single more powerful MCU or FPGA for it would decrease the complexity.