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linear actuations for everyone!

cheap artificial pseudo-muscles here

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Some time ago I thought... Why linear actuators depend on usual mechanics so much? Gears, worm-gears... Come on! So here it is, something that semi-soft, has no gears and also implements a lot of interesting concepts, like using pulling force and pivoting torque at the same time! Linear electric motor, if you wish :)

Target of this project is to create cheap semi-soft linear actuators for everyone to use
Project has two parts:
1) Structural one, about mechanics
2) Effective control

Structure
Main idea - to use pivoting torque and pulling force at the same time, it works like a linear electric motor. Two electromagnets on each side generate magnetic field, which orients magnetic momentum of each segment of the stripe.

(^ new design of stripes with magnets)
You can read more about production of stripes in logs of project, here I only would say that it's quite simple to fabricate them: you need 3d-printed mold. Then, you pour few liquids (including epoxy) there and clamp nylon stripe inside, as simple as that!

Control circuit and effectiveness
"Are electromagnets effective enough?"
- Yes, you just need to control them properly. We don't have to waste so much energy during their work, my theory is what electromagnet has a top energy capacity assigned to specific voltage which it can achieve and by cramming additional energy inside on top of that you do nothing, what is usually seen as a not energy-efficient behaviour of electromagnets.  You can withdraw and insert energy there cyclically without exceeding of any limitations.

During R&D lots of interesting things were found - how electromagnetism works in general and how to "do it" properly. Where are hidden losses, how to avoid them, what is a way to go and what is not.

You can read about it here: http://cafeohw.xyz/electronics/eism/

Benefits
Or why, in the first place? :

A) Semi-soft actuators would be reliable
A.1) Comparing to traditional rigid mechanics they don't care about shocks of any kind very much, also there is nothing wrong with bending - no requirements for precise placement for them.
A.2) You can parallel them - many hands make light work. If one fails - it's not fatal. And paralleling rigid motors isn't simplest task.
B) They can be fast
C) Why do you need to simulate muscle with complicated math models, if you just can use something, what is very close by design?

  • 1 × Epoxy glue usual epoxy
  • 1 × Nylon strap typical nylon strap, 2000 x 20mm
  • 1 × Magnets 10x6x3mm rare-earth
  • 1 × LM2903 SO-8 comparator
  • 1 × SN74LVC1G series logic gates NORx2, NANDx1, ANDx1

  • Full-fledged theoretical "How-to"

    CapitanVeshdoki02/04/2020 at 13:52 0 comments

    Hello! Made a site to publish theoretical info in convenient manner

    http://cafeohw.xyz/electronics/eism/
    ^ You can check it via that link

  • BLDCiing it forward

    CapitanVeshdoki01/21/2020 at 21:11 0 comments

    Next logical step - is to couple theoretical findings with BLDCs, it is fun, educational and even useful at some point! In previous update that was a brushed motor... Pretty unfortunate - it's hard to imagine worse enemy than brushes with that approach.

    I started to develop an experimental BLDC controller and imagine my surprise when I realized that circuitry, mentioned in previous posts, fits there ridiculously well! People, familiar with BLDC controllers, would probably notice that there is not much to change. Of course, specific control methods required and some hardware tweaks also, but hey, it's pretty neat : )

    Generally speaking - there are high/low side FET's connected to each phase of BLDC coil, therefore there is an opportunity to shortcut coil from GND to GND via that. Or from VCC to VCC. Providing low-resistance path for a current, low voltage drop and so on... (topics from previous posts)

    It's pretty pricey to implement analog current-control for each phase (thanks to DACs, low resistance and preferably hall-effect current measuring ICs, logic e.t.c.) - in this iteration, I decided to use old-fashioned way, outsourcing computational power and commands from an external MCU. Not the most elegant solution, neither a reliable one. Let's hope, that it would work without occasional fireworks.

    Compromise is to use onboard timer and only ON/OFF signal to switch coils would be sent externally, however it would be a tedious process to make it on one layer board, with all required logic IC's. Simplified everything to a maximum degree possible, with one current sensing IC for all 3 channels:

    Had lot of fun tracing that stuff! Aside of queer shape, it should have a damn good resistance and heat dissipation properties. Inductance should be less as well.

    Not sure, that I gonna manufacture this one soon, so there is a room for corrections.
    I'd like to make traces which go from drivers to a gates wider, as I see it now
    (there are interesting 4A source/sink MOSFET drivers)

    P.S. And that is our test subject!

    Motor has something around 30mOhm resistance, according to a manufacturer. Curious how it would play out, generally - low resistance would be a benefit, but with MCU-controlled board I'm pretty concerned about switching frequency. It's really easy to get sky-high currents that way x)

  • DC motors?

    CapitanVeshdoki01/18/2020 at 14:47 0 comments

    This time I've got a more direct reading than current. Pivoting torque.
    Before that, traditional links list:
    Theoretical parts:
    - Part 1 (how efficiency works while you charge an electromagnetic field)
    - Part 2 (why discharge time matters and how it affects heat dissipation)
    - Part 3 (that one was half-wrong, but heat dissipation part is likely to be true, read carefully)
    - Part 4 (what affects discharge time)
    - Part 5 (how to discharge field slowly using MOSFETs)

    Current is a great reason to assume that magnetic field is somewhere... there, but not that convincing - I can imagine some unaccounted nuances, there are lots of them, usually. And people try to decrease their amount by doing further research.


    It was necessary to prove, that along with current it produces appropriate force, as we use unusual methods to work with an electromagnetic field here, so I made that thing:

    That photo magnifier was unused for years! But it came in handy, finally

    On a right side there are digital scales. Fun fact, that they even have temperature compensation. I was really impressed with that, since they were pretty cheap. What I did - I checked, that with virtually same average current, pivoting torque is the same:As I mentioned in video - it works. Generally speaking - to maintain magnetic field, all you need is to counteract it's discharge rate on slow discharge phase and heat loses on a charge phase. In this experiment I've got this:
    1) I^2*R on a coil, about 8W
    2) Power, required to charge 3mH coil from approximately 1.3A to 2.2A 1000 times per second, about 5W
    Since duty cycle was 50%, we have (8W)/2 + 5W = 9W average.
    And it's important to notice, that only 4W goes to heating of a coil, compared to 8W with traditional methods

    Conclusion:
    - By decreasing resistance of a coil OR by increasing voltage we minimize heat loses
    - By decreasing voltage drop across slow discharge circuit (see Part 4) we can minimize power consumption
    Combination of those two methods is a win

    P.S. "Power distribution question": I don't know, why it charges field at that rate exactly, previously I thought, that it must be an unused part of U^2/R power, but now I see, that it's kind of different in reality. More complicated? Or opposite : )

  • Electromagnet discharge guide

    CapitanVeshdoki01/05/2020 at 16:36 0 comments

    Yep! Complete discharge guide!

    I don't want to repeat that was there previously anyway, so - links.
    Theoretical parts:
    - Part 1 (how efficiency works while you charge an electromagnetic field)
    - Part 2 (why discharge time matters and how it affects heat dissipation)
    - Part 3 (that one was half-wrong, but heat dissipation part is likely to be true, read carefully)
    - Part 4 (what affects discharge time)

    This time I want to make a finishing pass on discharge topic. It looks like that:

    In theoretical Part 4 we came to a conclusion, what voltage drop affects discharge time significantly. Must-read, but simplified - coil tries to produce constant current while discharging and it's a very easy task if voltage drop is minimal. One approach is to use a diode, however, 0.4V is pretty high. And that is where MOSFETs come to play, acting as a low-resistance load.

    Zener diode in MOSFETs structure is very helpful, since it can handle current until FET opened completely.
    That's why this process has 3 stages and not two.

    For example, we have 1A of current, conductive channel provides 10mOhm, U = I*R, voltage drop using this method is only 0.01V, 40 times smaller than what we have on a diode! There is a room to play, in different conditions channel shows different resistances. That's what I've got with a random transistor as proof of concept:

    As you can see, it discharges about two times slower. It might be not very obvious, since discharging curve is really steep at the start, however, looking at the end of discharging process - advantage is pretty clear.

    To replicate this results you only need two N-Channel MOSFETs and one high/low side driver to control them. Also, it would be great to use new DirectFets, since they provide very little resistance. Resistance is a main point there.

    Funny enough - everything, that was there during charging process, like current-sensing resistors connected in series e.t.c., doesn't make any difference on a discharge - it's a part of what is being discharged, not a load.

    Overall, that scheme is component-friendly, as long as you not trying to open Q1 and Q2 at the same time, shorting VCC to GND completely. There should be some sort of protection logic from that in case of control unit malfunction, it certainly would be on a next versions of control boards, but for test purposes... Why bother , )

    P.S. Looking forward to some low-rpm or stall-shaft tests in future
    P.P.S. I made additional attempts to conquer EM fast charge without high voltages, but for now with no results.
    Fast charge & slow discharge ideal loop isn't closed yet, but now we are 50% closer! Hooray : )

  • Discharge time and coils

    CapitanVeshdoki12/24/2019 at 20:56 0 comments

    In previous update I said, that if fast charging of field is impossible for now, I gonna try to find a way how to slow down discharge rate. I found one, so here it is.

    Interaction between a coil and a capacitor is kinda interesting one: coil itself tries to sustain current by any means and current is an amount of charge moving through wire each second, however energy needed to move one electron differs depending on your setup! It can be small, it can be large, and while you have limited amount of electromagnetic energy - it makes a difference.

    For example, if you have 40J in a magnetic field and each electron takes 0.5J to move through your coil, you can move only 80 electrons in total, with current in mind it dictates coil discharge duration. Let's say, that we need to increase that. One way to do it is to use bulky coil (with greater inductance), with same current flowing it would have more energy, not a great option though - it will increase cost and make coil more inert. Second, neat way, is to tweak amount of energy each electron takes to move - this is where capacitors come to play.

    First of all, where this energy comes from? It comes from voltage. Electron would move himself from negative (overpopulated by electrons) to positive (desert) side without need in external force, as it seeks lower energy state, but opposite is unnatural and some effort is needed. When you charge a capacitor - you move electrons in unnatural direction, where voltage is Q/C. Bigger capacitance means, that you can move more electrons without significant rise of voltage and therefore - less energy used to move same charge. That's how you can discharge same electromagnetic energy with same current longer and that's what we see in LC circuits, where period of oscillations is somewhat proportional to C.

    So... Can we simply increase capacitance? Of course we can, but there are much more elegant approach to that, which I found today! Let's nickname it... Battery-handled discharge. 

    What we can see there is pretty interesting. Ground and MOSFET at the top are used to charge coil. VCC is connected all the time, pre-charges capacitor to a power supply level. Right after ground is disconnected, coil charge capacitor and... does it in unusual manner! Electrons from capacitor's top plate are forced through coil, but not to the ground level - to the VCC level instead. It gives us really shallow potential difference (dV) and we win loooong discharge time! Other part of potential difference is handled by a power supply, while it tries to remain positive : )

    Here you can see how energy needed to move charge (aka dV) affects discharge time:

    How effective it is? From previous theoretical updates: field charging process becomes very-very ineffective as  it goes, so I tested it with a reduced charging time:

    As you can see, goal "discharge time > charge time" was achieved much more easily this way, without significant loss of current. And theoretically - there is a room for improvement! 

    Currently, there are only one limiting factor - voltage drop on a diode. That's a voltage drop, which cannot be defeated and great amounts of energy are wasted there, that limits discharge time. Maybe it's possible to replace it with another MOSFET, but I'm not sure for now.

    And last thing - what about efficiency? Is it bad, that power supply handles something? Really, nothing to worry about! All that energy goes to charge a capacitor, so it can be reused, obviously. It's not something, what is dissipated in form of heat : )

    P.S. Would be sweet to find a way to charge field faster, as I tried previously. But all that made me think: if slow discharge equals low voltage, doesn't that mean, that fast charge would always be a high voltage? Is it really possible to achieve it other way?

  • Ouroboros healed itself!

    CapitanVeshdoki12/23/2019 at 00:13 0 comments

    Hello everyone!

    One month later I debunk my suggestion from a previous log, that electromagnetic field can be charged insanely fast using capacitors as a medium. Partly it taken so long because I played with a new desktop milling machine, partly because I was trying to combine my previous schematics with not working one

    This is how it ended:

    I checked current, after all! And I had no idea that something was wrong there, as I was totally sure, that voltage drop (mentioned in previous log) has something with current, but it seems... that my oscilloscope was calibrated badly. Even if all seemed pretty logical

    After 70 conducted experiments, using indirect clues, I finally found that something was off!
    Checked, re-checked and here I am : )

    What does it mean for project - is that it thrown back a few steps. Important ones - it's not so convenient now and with boosted charging process it could've been a completed one. It doesn't mean that we left without options, however: using high voltage is a really questionable stuff to do, as alternative we can slow down discharging process - and it is a good way to go. It doesn't really matter, what we use - fast charge or slow discharge. Capacity helps with that - well known fact. And it's probable to find some additional methods if we are lucky, who knows!

  • Ouroboros is broken!

    CapitanVeshdoki11/12/2019 at 17:36 0 comments

    Ho ho ho! Here we go again! : )

    Do you remember my promise to come back if I would manage to develop charge-based electromagnet? Well, I failed with that, I can't solve this riddle, but... I have a mind-blowing alternative!

    This would be a long story, so I am gonna describe what I achieved in couple of words for readers not familiar with electricity and then I'm gonna head towards details and sort of theoretical explanation.


    Core problem of electromagnetic actuators (and all electromagnetic devices) is heating - it limits power/mass ratio and wastes precious energy onto something you don't generally need. In a situation when magnetic field isn't performing any work it's especially ridiculous.

    In previous logs I noticed, that dissipation isn't an attribute of current in a several case, but this case cannot close the circle alone: it was true only during discharge of a magnetic field. Before that I discovered, that voltage at some extent can reduce dissipation and started to develop a control circuit, which can operate under high voltages. High voltage is a real trouble to deal with!

    Briefly speaking, greater voltage can charge coil faster. But is it the only way to do that? No.
    You can hack a resistance itself. Superconductivity allows you to get very strong fields, this method also does. Later it can be used for transformers, drone engines, precision machines (to minimize thermal expansion) and, of course, it makes my "artificial muscles" possible : )


    Theoretical explanation and details

    Previous theoretical parts:
    Part one
    Part two

    1. Possible source of heat dissipation

    As we found, you can get current without a heat, traditional "frictional" explanation doesn't seem so fair. We know what voltage can be a result of a potential difference and "potential difference" redefined - difference in energies. Electrons flow from greater potential (-) to a lower potential (+)

    So... Energy drops! And where it goes? Maybe into heat. P=U*I, where U is energetic difference and I is amount of charge, which goes through that difference every second. Similarly, E = U*I*t, where I*t is an amount of charges which went through that difference overall.

    Let's consider three situations:

    First one is a typical situation with a resistance, voltage drop on which represents potential difference.
    Second one is a discharge of a capacitor onto coil, where potential difference produced by a capacitor.
    Third one is interesting one, as coil never takes voltage into account, only current, it would try to produce enough voltage to maintain flow of electrons, so voltage on a coil stays equal to voltage on a capacitor. There are still a lot of questions about this one, but it's the one with virtually no heating at all.


    > > > > > > Disclaimer! Next part is a wrong assumption! Left it there just for history : )
    2. Boosting a field-charging process
    To generate electromagnetic field we should achieve surface charge gradient (according to a first theoretical part) and it seems that this gradient is tightly bounded with current & voltage. But as we have a "perfect" discharging cycle which takes some time (this was in a second theoretical part), we can try to speed-up charging process that much, what it wouldn't dissipate much energy and efficiency would be close to 100%.

    There are two ways how we can move charges - non-insulated way, like we always do by attachment of power supply or a capacitor and external field way - insulated. Best way to generate external field is by a capacitor. Fun part - external fields never bothered by internal circumstances! And resistance is one of that circumstances. That's how we swap resistances here!

    Elegant, easy, all our problems with charging solved. Experimental setup was also simple:

    Relay was needed to connect VCC and GND simple way, without P-channel MOSFETS or high side drivers for them. It added some rattle in oscilloscope data though:

    Significant improvement. Voltage drop on external circuit resistance is very helpful,...

    Read more »

  • Control circuit V2

    CapitanVeshdoki10/15/2019 at 21:18 0 comments

    Hello everyone! Again : )

    Previously I figured out how to achieve a real efficiency gain, v1.2 circuit board had various limitations, as well as a few mistakes. Summer ended, now I have less time for my own projects, but I gain experience developing other stuff and I can implement it here!

    I reconsidered some aspects of a board, and that is what I have now:
    This time I chose distributor of electronic components who works internationally instead of our local shop, so I had a wider range of components to choose from! What's why now board features automotive connectors for example, way better than "PC" connectors stocked in our shops : )

    I added a DAC, sending PWM signal from MCU constantly isn't reliable at all, as well it gets affected by inductance of wires coming to a control circuit, e.t.c. e.t.c. Instead of that, we can use SPI, to connect great amount of independent boards. And I'm not choosing I2C, 3bit addresses for individual DAC's cannot give enough freedom if you're willing to connect 30 board at some point.

    As this iteration is suited to work with high voltages (300V max), optocouples are necessary to protect MCU, which can be quite expensive. I have high-side driver this time, it wouldn't dangle on wires somewhere aside of a board. Last time it confused me much, now I tuned this thing nicely and it should work well. Finally, you may notice test points - they should be very helpful for maintenance.

    Overall, design is much more robust now, can't wait to see it working, I have plans for that one. Now it should cope with power needed to my linear actuators and I really want to experiment with transformers and BLDC motors, this board is suitable for them too, as it is a general-purpose EM field controller.

    Bringing down heat dissipation of a conventional BLDCs gonna be fun :D

    P.S. PCB ships for about 30 days, components... I think they have same delivery time, so next update should be in December. Time passes by so fast! However, do you remember concept of charge-based electromagnet from previous log? It seems that I figured out how it possibly can be done, if it works, next update is much closer than December and it would be amazing. Why? Hm... )

  • Studying energy dissipation

    CapitanVeshdoki09/24/2019 at 17:54 2 comments

    I advise reading previous update ("Bye, DC!"), it's a crucial part - it contains important ideas about power & energy in electric circuits, revealing phenomenon of inductance and resistance on a new level - now it's my instrument of choice for working with electromagnetic processes.


    Hello everyone! Again : )
    Previously, I described a proportion, in which power allocates between charging electromagnetic field and heating a conductor and it was a bit of a shock for me, originally I wondered, how we can eliminate heat dissipation completely. Now it seems impossible? Not quite!

    I see two ways, how to come round that heating misconception:
    1) We can develop a new sort of electromagnets! If we assume, that proper distribution of charge in space (and not specifically in a conductor) creates a magnetic field, that means, that we can recreate it similarly to a capacitor. It would be a charge-dependant electromagnet, which can store electromagnetic energy as long, as charges present in it. In a traditional coil waste of power dictated by a unstable state of charges, covering a conductor - you need to apply external "force" to prevent "positive and negative charges" from collapsing, that's why applying voltage is an essential thing there. However, I failed to notice any sort of a magnetic field around flat capacitor. It doesn't mean, that it's 100% not there - it's probable, that Earth's magnetic field outruns weak field of a capacitor - it requires more studying. If I would get an idea how to make such a thing - I would share it here. It would be epic, if it's possible ; )
    2) We can exploit an interesting behaviour of a traditional coils. More on that in next part:

    Exploiting physics:
    Even an energy dissipation law has it's own backdoor! And this backdoor is a fact, that if you apply no power to a conductor and retrieve most of energy, that it gives to you, it's not likely to dissipate something into the air. Current might stay the same, who cares!

    I made some measurements:

    I submerged my electromagnet into a vessel with water and powered it up, recording changes in temperature. It takes about an hour to temperature to drop down for a 2 degrees in this setup, as it features some thermal insulation after all, water volume stayed untouched

    Here are results:

    Control circuit changed situation a lot - reducing energy dissipation for about 30%
    On the right side you can see oscilloscope date, isn't it looks familiar? :)

    That then, 30% is our upper limit? Not at all! Retention of energy goes on a constant rate independently of a charging rate, as it is a typical LC oscillatory circuit. We can use it in our favour, increasing charging speed. Here are few samples with another electromagnet:

    Using higher voltage, we get great charging:retention proportion, also - increase in a field-charging efficiency, according to a model presented in a previous update.

    Conclusion:
    Increasing retention time looks like a solution, can it be done by increasing capacity?
    Who knows! Time will show!

    Is it possible now to pump 300W into a electromagnet without burning it down?
    Theoretically - yes. But new version of a control circuit is needed.
    That one isn't suited to withstand such voltages & currents yet.

    Can we use these methods with BLDCs and stepper motors?
    Sure! With everything that has coils.

    It seems, that this project requires more time to finish. But it's so much fun!
    Then I started it, I never imagined, how many things gonna be uncovered.
    Stay tuned! I surely would finish it... Somewhere... )

  • Bye, DC!

    CapitanVeshdoki09/03/2019 at 14:30 0 comments

    This log would be very strange, I wanna introduce new physic theory
    Well, I tried to stop myself from doing that kind of work, kept saying "Just use that, don't trash your head with such an outrageous things, you have a lot of another stuff to do" - and here I am!

    Now, I want to list, what I don't like in conventional conception of electrical engineering:

    - If dissipated power is really U*I (according to Joule's Law), why then it's possible to perform any kind of work? To generate a field, which has energy, you should take that energy from somewhere, as we say that U*I equation is right 100% of time - it should be impossible, however, transformers, oscillatory circuits and electric motors have no problem with it.
    - If we say, that coil has an energy of field proportional to flowing current (L*I^2/2), then how on Earth it starts to charge? Traditional chicken & egg question. If we say, that there is no power without a current and no current without an energy...

    Needless to say, that traditional laws of physics had no chance to uncover the mystery how my circuit really works even partly. And I was OK with that, until I found efficiency problems in my design and tried to find a reason.

    I'm not pretending on universal truth and I have no intention to convince someone, but this theory explains electromagnetic processes much better, in my view, makes a lot of things clearer than ever.


    I want to start with a little bit of description, what is the origin of a stable current in the conductor. It's an experimentally proven (but probably not widely-known) fact: distribution of charge on the surface of the conductor.

    And it's fair to say, that as we have potential difference, we have potential energy between charged particles at least. Then I thought about reasons why my circuit is not as effective as needed, it was the first thing which came onto my mind: as I have diodes, it must be a tough work for magnetic field, to power up electric field and break through potential barrier!

    Idea of two energies on the surface of a conductor was very catchy and since that time I started thinking about it, as it seemed, that that charge is responsible not only for current, but for magnetic field, inductance and... resistance! Typically, we say, that we have two types of resistance: resistance and electrical reactance, probably it's an artificial division, caused by urge of numerical description and lack of understanding. That was OK for a typical AC applications, but not enough now, then we are talking about behaviour of an electromagnetic field.  Let's have a look:

    I wouldn't comment that a lot, as imagination is more important here. With same applied voltage, conductor with bigger section area have greater electric flux, and current raises proportional to R^2. On the other hand, electrical resistivity defines surface density of charge for a specific applied voltage, not a conventional "friction"  

    So every conductor has that properties. Difference is only how much "inductance" and "resistance" it has. Important to say, that potential energy between charged particle and energy of magnetic field are tied together. There is no magnetic-field energy without proper electric-field energy and vice versa!  For example: then you wrap wire around a steel rode, you add an object, which your wire needs to magnetize - it's harder now to cover a conductor with electrons and generate current, each potential difference there "costs" a part of magnetization process.

    Funny enough - there is even an interesting relation between temperature and energy, which you need to pump in. For some reason, potential energy between charges decreases with lower temperatures and conductor can gain more electrons proportional to that. I found that, then efficiency of my circuit increased as I put electromagnet in fridge. I think, same process takes place in superconductors (more pronounced) and in batteries at cold - amount of charge stays the same, energy decreases, there is no...

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Ian wrote 05/04/2019 at 05:37 point

Excellent work! I'll definitely be following this project closely. It seems you are progressing rapidly now, and the muscles are even more efficient.

Any chance the 3D mold files or PCB schematics will be made available anytime soon? I'm eager to join in on developing these actuators for a robotics application. I think they would make a suitable alternative for brushless motors if the torque could be maximized. Much more power efficient too!

  Are you sure? yes | no

CapitanVeshdoki wrote 05/04/2019 at 19:19 point

Molds are prototypes, there are still minor things to improve (talking about convenience of fabrication e.t.c.) and this is a main reason why I'm not into uploading alpha-versions now.

Talking about schematics - you can find it in project logs, it works pretty well already, on this week I gonna trace new version of a control circuit and PCB would be uploaded here. So yes, control circuit will be made available soon :)

I have intention to finish first version of an actuator in this month - 99% sure that full build instruction would be available in three weeks (3d-models, PCBs and related - as they are done, right with project logs)

  Are you sure? yes | no

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CapitanVeshdoki wrote 04/25/2019 at 11:10 point

Thanks!
Looking forward too - can't wait to implement them in some projects
(especially crazy ones)

  Are you sure? yes | no

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