• Project Log 23: I actually don't need the VR software.

    FulanoDetail01/23/2023 at 17:53 1 comment

    Monday, 14:46, 23/01/2023

    Well, I'm creating this other project log because my mind is a weird as ever.

    Every time I hit a wall, I feel like I didn't look up all the ways in this labyrinth of headaches that I call "project".

    So, I will try to look up how to configure the weight sensor, then I will try to check if there is a way of connecting the weight sensor to a PC, and then I will try to convert these digital numbers to a program.

    Then I will really start hitting my head to find how to transform these signals/numbers into a input for a suit.

    There must be a better way.


    I Just woke up and I feel like crap.

    I can't make heads of anything that I'm reading.

    All my motivation is gone.


    Off-topic:

    Can someone please make a flying warship game?

    The closest thing I can think of is World of Warships (that doesn't have flying warships) and Nebulous: Fleet command, which I can't buy because I'm broke, but I'm not sure if I will like, because it feels more like a super hardcore RTS game rather than a warship game.

    And also Highfleet, but that doens't have multiplayer.

    Yes, I do like flying ships, how could you tell?

    Definitely not because of my 300 pages worth of off-topics throughout all these project logs, isn't it?

    Artist is Jakub Rozalski on Artstation.


    Funnyly enough, I did asked around some discord servers I'm in, and I did find someone interested on making a game like this.

    Although both of us can't make heads of advanced game development, I think that making a warship game is more manageable, since the gameplay is really slow and weighty.

    Unfortunately, no one wants to make a game.

    It is like inviting people to make an expensive and difficult endeavor on the development of a game that will take (at best) half a decade without offering them money isn't that attractive, huh?

    Who would guess? hmmm


    Oh well, my classic smooth brain: deciding to make a lot of different projects all at once because I got bored.

    Now I need to manage my time making a f*cking mech, a VR suit (for the mech), an animation for a little animation challange, maybe a game and finding a part-time job to build the mech.

    plz help


    The program:

    To be honest, do I really need a VR suit taken from a VR haptic suit?

    I mean, I can literally connect the weight sensors directly to the progressive hydraulics valves, so the force the pilot applies to the sensors is the amount of fluid that is allowed to flow.

    Literally, I don't need the entire VR suit, programming, arduino, blah blah blah.

    But...

    I feel like it is not that simple.


    No, no, let's talk about this for a second.

    For some reason, I thought that "virtual reality = better mech control", which doesn't make much sense.

    I was thinking on some kind of robot simulation.

    But again, what kind of gain I would get out of this kind of simulation?
    By somehow sending the body movements, to a simulation like that, and then to the mech's body?

    Now that I analyse it, I can't see any benefit from that.

    The only thing I can possibly think is that it could be a way of dealing with sensory noise, but I could just use a simply program to use the average value (or common denominator) of the data it receives.

    However, I don't know how to do any of these things. :/


    I mean, I can totally think on some kind of programming logic, but I have absolutely no idea how to write the commands, how the programms interact with each other and so on.

    For example:

    -> Electromagnetic progressive valve avoids the magnetic fluid from flowing by keeping an electric current on it of "X value of voltage amperage" all the time.

    -> Sensor outputs "Y" value under input (the pilot is pressing it).

    -> The range of values the sensor outputs goes from "0% A value" to "100% A value", so "x% A value".

    -> The "X voltage amperage value" is decreased proportionally...

    Read more »

  • Project Log 22: Trying to make the software.

    FulanoDetail01/20/2023 at 12:25 1 comment

    It is Friday, 09:06, 20/01/2023

    Well, in the last 5 days I've been doing absolutely nothing, there are days that I simply look at all the tutorials that I need to watch until the night comes and I still do nothing.

    I'm making this project log kinda to force myself to start doing stuff.

    My mind every single day:

    And I still have to do stuff while being in this mental state.

    Lately I'm having to concentrate in order to remember what I was going to search on google, even though I already wrote what I wanted to research.


    Off-topic:

    In this off-topic I won't talk about flying ships, but about the artificial endoskeleton.

    In this video this guy uses a (apparently) cheap, light and small square tube was able to withstand 10 tons! 10 f*cking tons!
    The tube is a 1-1/2" X 1-1/2" square tube (basically a 4x4cm square tube).

    I'm trying to just lift 1 ton by applying 3 to 5 tons to the skeleton while equally spreading the damn weight light a bridge.

    Like, what the hell?!

    I'm so confused on the type of material I will need for the endoskeleton...

    Okay, I know that the pressure is slowly applied by a hydraulic jack, but even then, it is still 10 times what the mech is supposed to lift.

    Anyhow, I couldn't quite figure out the thickness of the square tube, but it seems something like, 1cm or half a centimeter thick.

    Also, another "life hack" that I found to be able to withstand more weight is inserting extrusions inside other extrusions.

    This technique was used on the spitfire fighter plane during WW2 (time is around 8:56).


    Now the probably off-topic subject, I decided to check again continuum robots because I felt unsatisfied with the results I got, and I got a really interesting design that it is really easy to build.

    As you can see, it is a really simple design that it "just" tubes one inside another.

    These are also easier to control (since there are a lot of scientific papers about exact prediction of them for 3d simulation/inverse kinematics).

    Well, this could be really useful on CNC machining, since you could have multiple ones substracting material and building the stuff.

    The problem is that I don't know how one would take off material in confined spaces without interfiring with the process, maybe Waterjet Cutter, mayber Fiber Lasers or Wire EDM.

    This eldritch looking *ss sculture is an aerospike rocket engine 3d printed on copper.

    Although I was actually searching the subject for using on the Mech's endoskeleton.

    I still don't know how to make this crap lift 1 ton of weight and still be safe to bystanders, but it seems like something that maybe can be useful.

    The thing uses conventional electric motors and conventional controls, but I have no idea what materials I should use, and how big this thing should be.


    Another topic that is kinda messing my mind these days is about the muscle contraction ratio.

    I know that in previous Project Logs I said that "maybe" the muscle contraction is ok or whatever, but I feel like the McKibben artificial muscles contracting around 6cm may not be enough to give full range of movement to the mech.

    And I'm trying to think in a way of extending certain types of movement, not necessarily for the sake of strength, but for the sake of motion range.

    For example, with this crappy sketch I've made on paint showing the actuators of the thigh:

    Imagine a second actuator that only works after the first actuator finished contracting.

    The problem is that if you connect the second actuator to the limb itself from the beginning, it won't be able to rest at the initial position, because the second actuator will just lock the limb in place.

    Then how the heck do you connect and disconnect the second actuator reliably in order to give it full range of motion?

    And yes, this is kinda necessary because, otherwise, this mech won't even be able to step up in a stair case.

    ... Read more »

  • Project Log 21: Options for motion capture suit.

    FulanoDetail01/15/2023 at 22:23 0 comments

    It is Sunday, 18:57, 15/01/2023

    Well, sorry in advance because this Project Log will take some time, a lot of time, in fact.

    Worse yet is that right now I'm sick as heck and I can barely step out of bed, I'm taking care of myself, so don't worry lads.


    Well, this Project Log didn't go as I expected to go, but I don't think I will be able to actually text any of the options presented here for the next weeks or so.

    Because I still need to make a program that translates the motion captured into something useful.


    Some problems:

    Anyway, to begin with, I strongly suggest that you watch the following video of the Hacksmith channel:

    They made a lot of mistakes that I honestly would have done as well, in fact, I think I would have done worse than that.
    I was thinking on literally buying 10 thousand brazilian bucks of stuff after finding a side job (around an entire year), but thinking about it now, it feels like it would be a really big mistake.

    Not to crap on them, but I feel like they should have started with a small plastic prototype before going to the real thing.

    I mean, maybe they wouldn't have bursted their budget if they thought and analysed all the problems more throughouly... Like with a smaller prototype.

    They literally had to change the hydraulic cylinders and the servo valves 2 or 3 times because they didn't considered the weight and the mechanical disadvantage these things would be under, like, they litearlly took something that is a heavy metal tool and it broke multiple times.

    Probably in the recordings and inner discussions were much more complex and better thought out than what it looks like in the final cut that went to youtube.

    And all of these problems makes me think:

    If these professionals took an entire year slamming their heads on this project, how much f*cked I am?

    They used the method of attaching an encoder on the rotating joints in order to control it with inverse kinematics, however, as you could see, know its position is not the same as knowing the force applied.

    Which gave me the idea (that I already had, but I forgot) of using the Piezoeletric buzzers as pressure sensors.

    And also using 9dof motion sensors, which confused me, but as said in this answer on Stackexchange, it seems like it is an super reduntant position sensor.

    And I was thinking of using that on the limbs of the Mech while also using rotary encoders, so I can have a better idea where everything is.

    The problem with all of that is the cost.

    Sure, the 9dof motion sensors are somewhat cheap (around 50 reais or 10 dollars), but the processing unit that they had to use... hmmmm

    Anything that is meant for processing and controlling robots is absurdly expensive, something as silly as a raspiberry pi can reach thousands of Reais.

    Of course, I can always f*ck around and find out with cheaper computers, but even then, I don't know how much will cost.


    The controls:

    As I have shown in my other project, the DIY Full-body VR Rigid Haptic Piezoelectric Suit, I have bought some time ago around 100 units of really small piezoelectric buzzers that I can convert to piezoeletric sensors.

    Well, once I get better, I will try to wire them in an attempt of controlling a VR hand, since, after all, both projects are interlinked somehow.

    ... And if I can virtually control something as sensitive and precise as the movements of the hands in a rigid suit, I definitely can do that to the rest of my body.

    The problem is... How?


    Of course, it would be a crime if I didn't mentioned the ideas that dekutree64 gave.

    Basically, he suggested to use a 3d printed plastic exoskeleton from a project in hackaday itself and use both the 9dof motion sensors and/or the fluid/movement of linear actuators (hydraulic or mechanical).

    Being honest, the reasons that I want to use rigid piezoelectric suit is completly for safety reasons and haptic...

    Read more »

  • Project Log 20.1: Actually I don't need to design much.

    FulanoDetail01/11/2023 at 19:42 3 comments

    It is Wednesday my dudes, 16:11, 11/01/2023

    Well, after much frustration with myself and a lot of thinking, I finally came to the conclusion that I cannot properly design an endoskeleton that demands highly engineering knowledge.

    And therefore, I will try to make it the simplest way I can come up with, but I cannot garantee it will withstand the 1 ton threshold.

    Of course, you can simply choose to use composite materials such as carbon fiber, fiber glass or wood+resin (or ultra high performance air-concrete).
    But, like I said, quality is also not a garantee when you make composite materials by yourself. Specially when you're building something to withstand 1 ton of weight.

    You could also use solid steel (or aluminium 6061/7072) rods with 9cm in diameter and 30cm in length, but it will still weight around 2 tons (or 600 kg if you use aluminium).

    Henceforth, with all this said, let's get this bread.


    Off-topic:

    Well, I guess off-topic topics are now a thing, since I can't just shut up myself.


    I forgot to actually right what I had in mind, lol.

    So... What I was trying to say:

    Pulse jet engines are a simple but extremely powerful type of engine, however, these have some defects.

    These aren't as fuel efficient as Turbine Jet engines of similar size/thrust, but they have superior thrust-to-weight ratio and are incredibly simple to make.

    (this guy sells his PulseJet projects, by the way).

    However, as you may not know (just like I did), pulse jets actually aren't detonation engines.

    These actually work with deflagration.

    The difference between deflagration and detonation would be something like the difference between a flamethrower and a explosive.

    Anyway, the thing is that there actually are detonation engines, that work by supersonic detonation.

    And as you could see, there are rotating detonation engines, which, as you could see in the video above, use a rotating wave of detonation that pulses the air in a spiral just like the blades of a Turbine Jet Engine.

    So, a turbine jet engine without moving parts.

    My mind just blew away with such concept.

    The thing is, that if you put obstacles in a tube in which a deflagration reaction is happening, it actually becomes a detonation wave.

    Who would guess that obstructing a wave would make it go faster?

    So... If you use a Pulse Jet engine that turns into a pulsed detonation engine and then stack a lot of those in a circle, and then ignite them in a rotating succession... You get a rotating detonation engine.

    Maybe.

    I couldn't find any examples like this.

    Maybe you would need to reintroduce fuel in the pulsed detonation chamber in order to make it work better, but... Who knows?

    Image took from the article: "Review on the Research Progresses in Rotating Detonation Engine".

    So, if you put enough of those in a mech...

    Would you be able to rocket thrust around like in the games/animes/movies?


    The Endoskeleton Bones:

    Well, like I should have done since the beginning, I will use trusses made out of wood.

    I mean, it was so simply and in front of me all this time, I could've just used them.

    Here it is what I mean:

    See these metal plates? These are called brackets, so you can literally "just' take a plate of metal and go using both as a holder for nuts and bolts and as a structural reinforcement.

    Not to mention that Oak wood can have the density of 0.82 g cm-3, meaning that, even if you were to use solid Oak wood rods with 10cm in diameter and 30cm in length, the entire structure would still weight just 247kg.


    ... Wait...

    Waaaait...

    Wait, even if I use solid Oaks as an endoskeleton, then why should I waste time desinning the damn truss structure?

    I mean...

    I could have done this since the beginning...

    Just using wood...

    And I could even cut the wood in different shapes, so I could make a knee...

    Read more »

  • Project Log 20: (NOT) Designing bones with FreeCAD.

    FulanoDetail12/30/2022 at 19:43 2 comments

    Friday, 16:41, 30/12/2022
    Tuesday, 18:01, 10/02/2023

    Look, my apologies, but I didn't do anything.

    I just feel like this project log has become just a lump of frustration and uselessness.

    It is just... I keep looking at the fricking wall of tutorials, and I keep looking at the clock, and the hours simply pass.

    For some reason I just feel frozen, and the fact that I took 20 days to do absolutely nothing just fills me with anxiety.

    When this "mind block" goes alway I will make a new project log.

    I just want to forget this thing for now, I just feel frustrated with all my failed attempts by now.


    So, I just found out that I could simulate this kind of stuff on a program called "FreeCad", which, if I figure out how to use, can help me a lot.


    Also, New Year y'all, I hope I finish this DIY Mech project this year instead of coursing 5 years of engineering.

    Also, sorry in advance, because my brain is not working and I don't feel like working on this migrane of a project right now.


    Off-topic:

    You know what time is this bois?! It is time to write 30 pages of useless knowledge that nobody cares.

    Remember when I was talking about Ionocrafts on Project Log 17? So... I was wondering something.

    (content warning, if you have arachnophobia)

    Spiders, somehow can fly using static electricity, like balloons in the wind.

    I wonder if it would also happen to an aircraft using more or less the same principle...?

    Also: the video I showed saying that ionocrafts are aboslutely not viable is kinda misleading, the own wikipedia page the guy shows tells that the low "1 watt per gram" ratio of ionoctafts were only found on early 60's prototypes.


    I asked around and it seems that this method of flight is also a no-go. It is definitely not scaleable since the cratures that use this type of flight have less than 10 miligrams of weight.

    Well, there it goes my dream of a creepy flying object full of electrically charged spikes and strings... 🥹

    (yes, this is from Matrix)


    Also, I totally forgot about a subject about ion propelled aircrafts: they are similar to the speed-size "ratio" that the conventional aircraft have.

    Dunno if it is a real ratio, but... basically, the bigger the propeller blades of a turbine, rotor or other type of propulsion, the bigger the lifting generated, but its speed is severely affected.

    That is why aircrafts with smaller propellers waste so much energy trying to fly vertically compared to convetional big rotor craft.

    Well, the thing is: it is not so different about ion propelled aircraft, they need those big wings because the wings are the propellers.

    So, you either make them ginormours, or make them smaller, but with greater speed.

    In either way, just like in the conventional aircraft, you will have advantages and disadvantages for each type of propulsion system that you need to verify if these align with your required parameters.

    Source of video here: "Designing A Next-Gen Ionic Thruster! (For Flight)".

    And, of course, the same applies for wings, aircraft size and so on.


    Oh yeah, I also remembered something:

    Basically, you can kinda "cheat" the size of your wing span if you increase the number of wings.
    Of course, this comes at the cost of increased drag/friction on air.

    That's why some old aircraft used double wings, and why some modern aircraft have some complicated wing dividing mechanism when it comes to landing and taking off:

    I wonder if one would be able to make a flying ship with enough small wings... 🤔


    Also, I just found out about Kite-surf and Paragliders.

    Isn't it crazy that one could simply fly (with enough paragliders/kites) using these methods hundreds of years ago?

    We could have flying sail ships, but real life is just too boring, ain't it?

    (wallpaper...

    Read more »

  • Project Log 19: still (sorta of) designing the Bones.

    FulanoDetail12/30/2022 at 11:46 3 comments

    Friday, 08:37, 30/12/2022.

    So, let's try again to go designing the bones.


    Something that I totally forgot when calculating the weight of the skeleton: Density.

    You know drag cars? Those cars that literally work on speeds so fricking intense that they can only work one race and breakdown?

    So, they use aluminium, because aluminium is just 1/4 of the density of steel, so if you make an aluminium bar bigger than a steel bar in order to withstand the same weight as a smaller steel bar, it would weight more or less half (or even a third) of the weight of the steel bar.

    This guy explains it better than me:

    So... Calculation time:

    Well, I forgot to write the calculation, but basically, a 9 cm diameter 30 cm length aluminium rod would weight just 5 kg, which in total woud weight around 600 kg (1322 pounds).

    However, just like I said, I would need to make it bigger, so I tried something around 15cm of diameter and I got 15kg per rod, which would give the same results in the projec log 18.


    Like I said on Project Log 10, the joints of wrists, torso and all that stuff will all be universal joints.

    But the only universal joint that I think would be able to withstand fricking 5 tons would be universal joints for trucks/tractors, and of them costs 200 Reais (37 dollars) each, and I need around 16 of those.

    So... 3200 Reais (605,30 dollars) just for the joints.

    AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA

    Yes, I know that the muscles need to lift 5 tons, but the overhaul weight will still be just 1 ton.

    But, as you know: all the weight of walking, running and jumping will be going down on the legs and feet, and these will absolutely need to be extra resistant.

    I'm also guessing, of course.
    These things are meant to rotate, not to withstand impacts.


    Another big problem is that carbon fiber is terrible when it comes to screws, and joints.

    Those metal connections on carbon fiber tubes need to be inserted before the resin is applied to the fibers.

    How to I apply this to the writs, to the shoulders, to the elbows, the knees, the feet?

    Worse of all, carbon fiber is terrible against impacts.

    But I was thinking on possible solutions for these problems, I just don't know how to calculate if they would actually work or not.

    The idea was to either:

    • Make a Matryoshka of tubes of carbon fiber and tubes of steel one inside another. So the impact would be dispersed on the maleable steel/aluminium, and the weight be sustained by the carbon fiber.
    • Insidert a carbon fiber tube inside a steel tube.
      The steel would protect the carbon fiber from impacts and the carbon fiber would sustain the weights.

    Probably none of the above would work, nor be light or cheap.

    And I don't know how to make the universal joint rotate on its axis like those Stewart Platforms do.

    I'm also not being able to find heavy duty ball joints for vehicle sor anything like that.

    Bruh, I just need the wrist to rotate, why is this so hard? y-y


    I also found this company called "Dragon Plate", which specializes on carbon fiber modular structures.

    They showed this (impressive) picture of a 500 lbs (200 kg) at a distance that I don't know which.

    Just to remind you of mechanical levers: the greater the distance from the basis of the structure, the greater the weight it is applied to it.

    So, even though it is "just" 200 kg on the tip, it is actually an even bigger weight on the bars in the other tip.

    I took a random online torque calculator and assuming this contraption has 3 meters of length and the 500 lbs is completely applied to the extreme outer tip, this would be applying 63 thousand kg force per centimeter (of torque).

    But this isn't a rotating mechanism, this isn't a torque matter, but even then...

    Maybe I should use the work distance equation?

    Work = Force x Distance.

    So:

    • 1961.33 newtons x 3 = 5883 n . m or 5883...
    Read more »

  • Project Log 18: Let's design the bones!

    FulanoDetail12/26/2022 at 16:46 1 comment

    Monday, 13:38, 26/12/2022

    I didn't had an idea for a Project Log 18 yet, but since I added so many off-topics on Project Log 17, my Hackaday website started to lag and I was afraid of resulting in the same problem/bug that happened in the Project Log 16.


    Now that I think about it...

    I feel like the Project Logs are taking more and more time to be made and its subjects are getting harder and harder to calculate.

    The fact that I procrastinate 80% of the time doesn't help...

    But I do feel that I deeply underestimated the difficulty to actually complete this project log in specific.


    And guess what? I was right.

    I barely scratched the surface of the 2º topic, and the Project Log is already lagging and bugging.

    So, unfortunately, I will be forced to postpone the 3º topic to other project log, because I feel like I will beat my head a lot trying to figure out the structure.


    Okay, first, let's list what I need to talk about in this project log:

    1. Materials:

      Let's talk about possible materials that I could use.
      Such as Aluminium, Steel, Carbon Fiber, Wood etc.
    2. Fuselage and structure:

      Then let's find the best shapes these materials could withstand force and how to calculate these things.

    3. 3D modelling.

      Let's design a basic 3D sketch model based on these new shapes.

    Off-Topic:

    Also, I just found out about wax motors

    and it gave me an idea. Basically, Wax Motors are linear actuators that are used as solenoid valves in some applications. It uses a wax-copper/heating element mix, which helps melting it.

    Obviously, I won't use paraffin wax actuated McKibben muscles, simply because they are slower than a snail.

    However, as you people may remember from Project Log 1"polyethylene/nylon artificial muscles are not viable for control and actuation, because they are slow and need a lot of surface area".

    HOWEVER, if I mix copper powder, heating element powder (like carbon fiber powder) just like the wax motor, I will (maybe, perhaps, I think, probably) exponentially increase the contact area between the nylon and MAYBE allow it to contract like a muscle without the need for kilometers and kilometers of nylon fiber.

    I will just buy a 5 dollar nylon rod from aliexpress or something like that and then test it out (with aluminium foil and graphite powdered in a blender), I will need to make a lot of holes so the nylon can easily contract and cool down with circulating oil.

    (yes, this was an impulsive purchase that I will regret for the next 99838923 years, even though it is just a couple of bucks)

    Or, maybe, I think I will try to pass air flow through the molten nylon in order to make it porous, or just mix it with alcohol and wait the thing to scape (and not burn my house down).

    One could make a personalized 3D printing filament in order to do that, but I don't have the money, nor the will to get all that trouble.

    Art taken from Vitaly Bulgarov Artstation account.

    And yes, he did make the concept arts for the Ghost in The Shell live action movie. The script is bad, not the art, and for a good reason. ;)


    1. Materials:

    Besides, I could just use carbon fiber...

    Wait, no. Actually, I'm avoiding using carbon fiber and/or fiberglass.

    Simply because these two are messy and dangerous to work along without any kind of protection, not to mention that these can't be recylced...

    I could use wood with resin tho...

    The original article about the subject: "BYU Engineering Student Develops Bamboo Fiber Composite Material".

    There are also Wood-plastic composites:

    I could use polyethylene (a strong type of plastic, used even in bulletproof vests and milk jugs) as a matrix/binder and wood fiber composites.

    A few types of composites.


    2. Fuselage and Structure:

    I don't think I talked about this clearly enough on Project Log 16,...

    Read more »

  • Project Log 17: Calculating Hydraulic Accumulators and (some) Costs.

    FulanoDetail12/23/2022 at 16:34 0 comments

    Friday, 13:32, 23/12/2022
    I will try to finish this now, I swear.

    Again, not mfixing grammar mistakes.

    Well, the Project Log 16 bug definitely deleted all the things I wrote at topics 2 and 3, it is not like I just wrote the title and didn't work on anything at all. hehe. >.>

    The project logs that I wrote are basically this meme, lolololol.


    1. Hydraulic accumulators.

      Basically, one could simply use a cheap 12V tire inflator/air compressor to fill up a bladder hydraulic accumulator. But these are expensive, and I don't know how long a 300 PSI air compressor for tires will take to fill up homemade sketchy bladders. Also, pneumatics are kinda dangerous, they can explode.

      Also, one doesn't really neeed bladders, I could simply use a car spring that is pulled by a electric motor. Like a electric jack/linear actuator. When the spring is pulled, the hydraulic oil will be forced in by vacuum action, then I just need to release the spring and the compression of the spring will compress the hydraulic fluid and that's it.

      Kinda of, I need to find a way of calculating that. I remember once reading an scientific paper of a "novel design of hydraulic accumulator" or something among these lines, I need to find it again. Maybe they have a model/equation that I can use to guess how much pressure it will generate, if there isn't already an option that I can buy online. For some reason, the electric jack/lineart actuator is more expensive than the hydraulic jack... Bruh.

      Found the article: "A novel pump design for an efficient and compact Electro-Hydraulic Actuator IEEE aerospace conference".

      No, actually, I think it was this one: "Development of a novel compact hydraulic power unit for the exoskeleton robot".

      Or I could simply use a electric jack directly compressing the hydraulic fluid...  I could also make a homemade pulley that pulls the hydraulic accumulator spring. Homemade because the fricking electric pulleys use the same 1hp electric motors the high pressure hydraulic pumps use, so... bruh.  Dunno what is the best option, I will need to calculate every single one of these. I hope the people I invited to this project could be able to give me a hand, we probably know as much as each other, but 4 heads think more than 1.
    2. Costs.

      I was thinking a little bit here about the overhaul cost of this mech. A single car in Brazil can cost 100,000 Reais, but in the US it costs around 30,000 Dollars (as foretold by google). If we can make this thing under 10,000 Reais (or just 2000 Dollars), doesn't that mean it is actually very cheap to make one in comparisson to cars?

      hum 🤔 For example, if I used 72 5 ton hydraulic jacks that normally cost 100 Reais (19 Dollars) each, I would be expending 7200 bucks on the actuators alone, more 2000-3000 on the electronic parts including the hydraulic pump. This means this thing would cost kinda okay...? 🤔 (Not okay to me, I'm broke).

    Off-topic:

    Anyway, my brain is ADHD, and I will elaborate, and I won't make things clearer.

    So, with this said, let's get back to continuum robots:

    I found this continuum robot from the article: "Multi-Segment Parallel Continuum Manipulator".

    You could replace the disk with cables/wires, no?

    How to make this thing lift 1 ton, tho?

    And it is cable-driven by electric motors, not artificial muscles...

    Would it stumble the same problem I talked on Project Log 16? Where you need it to be so resistant to bending motion that it would simply become solid?

    I don't know, it is morning right now, my brain isn't working properly (when it does, tho?)...

    There must be a way of making this crap safe to be around that doesn't require the mech to look like a Michelin Man...

    You know, it is not because it will look stoopid or anything like that, it is because it is not...

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  • Project Log 16.1: Calculating fluid flow.

    FulanoDetail12/23/2022 at 16:29 0 comments

    Like I said on Project Log 16:

    The text gets deleted every time I add something.

    So, basically, at the end, the text is cut out.

    But, in summary, the informations that got deleted are:

    You can't make an electric motor actuate an hydraulic pump at 1000 RPMs, because when you increase the RPM, you decrease the torque.

    So, it would be more or less 200 rpm.

    This is bad and good, bad because I won't be able to make a fluid flow of 900 liter per minute, but I can use cheaper and smaller electric motors that have reduction gears.

    The recalculation of the pump, counting the space the piston rods occupies on the two motion cylinders gives 15 liters per minute at 3 bars in total. This accound the 5 cylinders used as hydraulic pumps.

    Edit²:

    Obviously, the pump wouldn't be 100% efficient, so we can cut that flow to lower values, around 10 or 8 liters per minute.


    Edit¹:

    As you can see in the video, torque/horse power, speed and energy consumption can vary a lot.

    If I where to use the big 3 hp 300 watts motor, I would definitely be able to supply the 900 liters per minute without the need of hydraulic accumulators.

    But, as you can imagine, it requires more energy, it weights more and it is much more expensive.

    And I'm trying to make this thing under a budget, because, you know, I'm broke.

    And to worsen things more, I'm almost reaching the maximum weight of the mech. Even though all the muscles can lift at least 5 tons.

    As you can expect, everything has weight. All the hydraulic fluid is around 150-200 kg (including the hydraulic accumulators, the batteries, the electronics and the pilot would weight 150 to 200 kg (or even more). I don't know how much the endoskeleton will weight, but a structure that can hold 1 ton will definetly be heavy as heck. At best scenario, 200 kg (if I don't use composite materials, just steel tubes).

    So... 600-800 kg in total, even though there are more muscles on the torso and lower part of the body, would it even be able to lift itself?

    I mean, there are 6 muscles on each thigh and each leg, each muscle can lift 5 tons... So... 120 tons in total... If we take the general mechanical disadvantage where each muscle would lift just a fifth of its total strength, we would get... 24 tons...

    Now that I think about it...

    Maybe a 3hp that weights 20-50kg and consumes 3000 watt/hour may not be that... Difficult?




    There must be something wrong with my calculations, if it was this easy to lift this amount of weight, we would have seen more mechs out there.

    There must be something wrong...

  • Project Log 16: calculating fluid flow.

    FulanoDetail12/19/2022 at 19:08 5 comments

    Thursday, 16:41, 15/12/2022

    20/12/2022
    Sorry for the delay, for some reason my brain refused to work these last 5 days, so I didn't work that much on this project log as I wished to.


    23/12/2022

    For some reason, it seems like this Project log is so long that the Hackaday website is lagging and bugging, basically, the topics 2 and 3 got deleted, so I will be forced to work on hydraulic accumulators and costs on the next project log.

    Just you got an idea, at the end of the project log, the text gets automatically deleted when I add something.

    I added what the Project log deleted at Project Log 16.1



    I'm putting here all the subjects that I couldn't talk about in Project Log 14:

    1. Hydraulic pumps and its relation to high pressure artificial muscles. I need to calculate the amount of flow.

      My first thought was, like I said in the Project Log 13, using manual hydraulic pumps with electric motors. I thought it was the best option, but the pressure is generated too slowly, so I would need a hydraulic accumulator, and the following reasons will clarify why.

    2. Hydraulic accumulators.
      Basically, one could simply use a cheap 12V tire inflator/air compressor to fill up a bladder hydraulic accumulator. But these are expensive, and I don't know how long a 300 PSI air compressor for tires will take to fill up homemade sketchy bladders. Also, pneumatics are kinda dangerous, they can explode.

      Also, one doesn't really neeed bladders, I could simply use a car spring that is pulled by a electric motor. Like a electric jack/linear actuator. When the spring is pulled, the hydraulic oil will be forced in by vacuum action, then I just need to release the spring and the compression of the spring will compress the hydraulic fluid and that's it.

      Kinda of, I need to find a way of calculating that. I remember once reading an scientific paper of a "novel design of hydraulic accumulator" or something among these lines, I need to find it again. Maybe they have a model/equation that I can use to guess how much pressure it will generate, if there isn't already an option that I can buy online. For some reason, the electric jack/lineart actuator is more expensive than the hydraulic jack... Bruh.

      Found the article: "A novel pump design for an efficient and compact Electro-Hydraulic Actuator IEEE aerospace conference".

      No, actually, I think it was this one: "Development of a novel compact hydraulic power unit for the exoskeleton robot".

      Or I could simply use a electric jack directly compressing the hydraulic fluid...  I could also make a homemade pulley that pulls the hydraulic accumulator spring. Homemade because the fricking electric pulleys use the same 1hp electric motors the high pressure hydraulic pumps use, so... bruh. 

      Dunno what is the best option, I will need to calculate every single one of these. I hope the people I invited to this project could be able to give me a hand, we probably know as much as each other, but 4 heads think more than 1.
    3. Costs.
      I was thinking a little bit here about the overhaul cost of this mech. A single car in Brazil can cost 100,000 Reais, but in the US it costs around 30,000 Dollars (as foretold by google). If we can make this thing under 10,000 Reais (or just 2000 Dollars), doesn't that mean it is actually very cheap to make one in comparisson to cars? hum 🤔 For example, if I used 72 5 ton hydraulic jacks that normally cost 100 Reais (19 Dollars) each, I would be expending 7200 bucks on the actuators alone, more 2000-3000 on the electronic parts including the hydraulic pump. This means this thing would cost kinda okay...? 🤔 (Not okay to me, I'm broke).

    Quite the off-topic here, but...

    I just love these arts from Theo Stylianides (I took this image directly from ...

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