• Project Log 7: Screw the Piezoelectric sensors

    FulanoDetail01/15/2023 at 22:58 0 comments

    Today is Sunday,  15 of january, 19:54 Brasilia timezone

    So, I was writing the Project Log 21 of my DIY Human-sized Mech project (that right now may be still in draft state), and I got a better solution than the piezoeletric buzzer sensors.

    Basically, instead of using both the piezoelectric buzzers as an input and output for haptic sensors, you could instead simply use cheap precision scales for food as your pressure/movement detector.

    And you still could use them above a lot of padding without the risk of blinding the sensors.

    The problem is finding a way of connecting these to a computer and a program.

    Anyway, one could still use the piezoelectric buzzers as touch feedback.

    By the way, sorry for the long months of no activity, since both projects are interlocked with the motion capture suit, I will post here the final result of the suit before even starting to make the mech.

  • Project Log 6: These AI's are out of control.

    FulanoDetail12/17/2022 at 20:13 0 comments

    Today is Saturday, 17 of december, 16:57 Brasilia timezone

    Well, sorry for the silence, I'm trying my best.

    So, well, there is an AI called "ChatGPT" which is a chat bot that can code for you.

    I can literally ask for equations about temperature, electricity generation and this thing always has an answer, it is madness!

    Anyway, I'm starting to ask for suggestions by this AI on how to program the Piezoelectric Full-body VR Suit, and it is giving me interesting answers.

    First interaction:

    "Yes, it is possible to use piezoelectric buzzers as a touch or pressure sensor and use the resulting electric pulses to control a 3D model in a game like VRChat. Here is a high-level overview of the steps you would need to follow to achieve this:
    1. Set up the piezoelectric buzzer: First, you would need to set up the piezoelectric buzzer and connect it to a microcontroller or computer that can read and process the electric pulses generated by the buzzer. Depending on the specific hardware you are using, you may need to write code to read and interpret the electric pulses from the buzzer.
    2. Map the electric pulses to body movements: Next, you would need to map the electric pulses generated by the piezoelectric buzzer to specific body movements in the 3D model. This could be done by creating a lookup table or using machine learning algorithms to train a model to associate specific patterns of electric pulses with specific body movements.
    3. Integrate the piezoelectric buzzer with VRChat: Finally, you would need to integrate the piezoelectric buzzer and the code you have written to interpret the electric pulses with VRChat. This could be done using VRChat's API or by writing a plugin for VRChat that connects to the piezoelectric buzzer and uses the electric pulses to control the 3D model.

    I hope this helps! Let me know if you have any questions or if you would like more specific guidance on any of these steps."

    Second interaction:

    "Yes, it is possible to use piezoelectric sensors to detect touch or pressure and translate that into body movement in a 3D model inside a game like VRChat. Here is an example of how you could approach this problem:
    Set up the piezoelectric sensor to detect touch or pressure and output an electric pulse. You will need to follow the manufacturer's instructions for connecting and configuring the sensor.
    Use a microcontroller, such as an Arduino, to read the electric pulses from the piezoelectric sensor and convert them into digital signals.
    Connect the microcontroller to a computer via a USB connection.
    Write a program that runs on the computer and communicates with the microcontroller over the USB connection. This program should receive the digital signals from the microcontroller and interpret them as body movement.
    Use the VRChat API to control the 3D model in the game based on the body movement data received from the microcontroller.
    It's important to note that this is just one possible approach to implementing this functionality, and you may need to adjust the details depending on your specific requirements and hardware setup. Let me know if you have any further questions or need more specific guidance.
    import serial
    import VRChatAPI
    # Set up a connection to the microcontroller over USB
    ser = serial.Serial('/dev/ttyUSB0', 9600)
    # Create a VRChatAPI instance
    api = VRChatAPI.VRChatAPI()
    # Set up the 3D model's initial positions and orientations for each limb
    head_position = [0, 0, 0]
    head_orientation = [0, 0, 0]
    neck_position = [0, 0, 0]
    neck_orientation = [0, 0, 0]
    thigh_position = [0, 0, 0]
    thigh_orientation = [0, 0, 0]
    leg_position = [0, 0, 0]
    leg_orientation = [0, 0, 0]
    arm_position = [0, 0, 0]
    arm_orientation = [0, 0, 0]
    forearm_position = [0, 0, 0]
    forearm_orientation = [0, 0, 0]
    thorax_position = [0, 0, 0]
    thorax_orientation = [0, 0, 0]
    abdomen_position = [0, 0, 0]
    abdomen_orientation = [0, 0, 0]
    # Main loop to continuously read data from the microcontroller and update the model's positions and orientations...
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  • Project Log 5: Maybe balloons?

    FulanoDetail12/01/2022 at 12:45 0 comments

    Today is Thursday, 1 of december, 09:38 Brasilia timezone.

    I'm definitely not procrastinating, hehe... 👀

    So I was thinking about the problem with the padding (and a lot of other things) that I talked about on Project Log 3, and it came to my mind that maybe I could use low pressure balloons/cushions as a padding.

    It wouldn't be as messy and expensive as using liters and liters of polyurethane or silicon, but they could be bought from stores (or online).

    Just imagine something like bubble wrap, like those really big ones.

    where to buy big bubble wrap Cheaper Than Retail Price> Buy Clothing,  Accessories and lifestyle products for women & men -Jual UKURAN PALING TEBAL Bubble Wrap Anti Pecah 5 Meter Ukuran Besar /  Inflatable Bubble Packaging / Air Bag Cushion /Air Bubble Packaging |  Shopee IndonesiaThat's it, I guess, I didn't make a lot of progress on anything (history of my life >.>).

  • Project Log 4: I should have read it

    FulanoDetail10/10/2022 at 18:54 0 comments

    Today is Monday, 10 of october, 15:52 Brasilia timezone.

    The piezoelectric "coins" arrived, and I should have read the description properly... Look at their size, they are smaller than my nails...

    Also, if the 2 people that still remeber this project, I'm having a lot of problems on my life and it is forcing me to ignore a lot of personal projects.

  • Project Log 3: Thinking a lot

    FulanoDetail09/26/2022 at 22:40 0 comments

    Today is Monday, 26 of September, 18:47 Brasilia Timezone.

    Well, s***, I decided to make at least some kind of 3D model, but it took me too much time.

    I feel particularly disappointed with myself, specially since instead of making everything from scratch on Blender (free program with a ton of tutorials on youtube), I searched for free 3D models of some things. I feel like I didn't put enough effort on it...

    Of course, all of these models look like... Acceptable things that are freely accessible, the good part is that they are normally low poly, so my potato PC doesn't choke.

    OH YEAH! There is also that: my current computer probably won't be able to withstand the processing load of even rendering a VR scene.
    Isn't that a really important thing to think about before buying 200 units of piezoelectrics for a goddamn VR suit?
    Isn't that the mind of an idiot?

    Yes, I found pretty ones, but they need paid programs to even be opened (which I don't have).

    Well, anyway, let's discuss about a problem that I just conceived today:

    Vibration cancellation for neighbourhood piezosensors:

    You see, since every piezoelectric actuator and sensor (they are the same thing, you just use/wire them differently), will be really close to each other, and both work on the principle of vibration/pressure...
    How do you avoid the actuators from activating the sensors?

    Maybe you could apply a tolerance range of detection on the sensors and a maximum range of vibrations on the actuators. So they don't start feeding each other endlessly. However, for now I can't tell if this will be enough.

    You see, it could be fine for the legs and arms, since they usually would make quite strong movements anyway. The problem is on the hands.
    They are very delicate and quite sensible to texture, and if you read all the logs from beginning to end, you would know that using piezoelectric crystals, you could create textures with different vibrations.

    It will be really necessary to strike a balance between the precision of the movement of the hands and the tactile texture of the haptic feedback, or else everybody hands will be shaking all around in the virtual world.

    Not to mention that the piezoelectric "coins" (as shown in the image above) aren't small enough to fit the shape of the hand, meaning that I will have to cut them to size; Which could destroy a lot of them.

    There is also the detail that the entire body will be held in place, what could lead to a big discomfort for the users. Imagine trying to walk, run or carry objects on the virtual world and not moving at all in real life? Wouldn't that need some padding?

    This could completely nullify the vibrational haptic feedback from the suit.

    Okay, maybe you could get around this with those cheap and small vibration electric motors you normally see on Playstation controllers. And maybe you could program the piezoelectric crystals inside the padding by detecting the vibrational frequency that they produce.

    Another idea for the cancellation of the vibration is to make a series of switching piezo-roles, so to speak. One piezo-actuator, one piezo-sensor and so on. But adding a little big of some kind of padding between them, like polyurethane (or just silicon).

    In resume, Polyurethane is a widely used material that can be tweeked to do almost everything, from shock absorbents (that are used to protect space rocket equipment) to soundproofing, thermoinsulating and fireproofing things (again, there is an incredibly amount of varieties and the ones that you buy may not do all of these things).

    Good polyurethane is normally expensive as f*** (in my country [Brazil]), but you could find them in the form of liquids that can become rubber-like bushings, foams and even modelling kits on the internet. And they are quite efficient as well; I saw videos of people literally using polyurethane from less than 25$ for mechanical car pieces, in specific on transmission mounts.
    There is also the expansive polyurethane...

    Read more »

  • Project Log 2: Possible VR Goggle or Headset

    FulanoDetail09/25/2022 at 22:56 0 comments

    Today is Sunday, 25 of September, 18:58 Brasilia Timezone

    Being honest, I don't have very much going on, the Piezoelectric crystal "coins" will arrive around 20 of October. Basically, a month without doing much.

    I will start planning the ins and outs of the rigid suit/armchair tomorrow with a 3D model (I hope), so I can easily calculate the amount of money I will need to build one. For now I'm thinking on buying PVC tubes and pillows to make a ultra-comfy armchair.

    But I'm just writing this Log because I feel kinda bad for not keeping daily uptates on my projects, and I don't think it would be good to worry about the goggles at this stage of the project. Specially since the software part of the suit will be a nightmare... But let's get going anyway...

    The VR goggles:

    Now, a VR-Suit isn't much without VR Goggles. And VR goggles are expensive as f-heck, even though they are cheaper than the VR suits available on the market. I mean, the VR goggles that uses cellphones as the screen aren't expensive at all, you could even 3D print one at home.

    In fact, there are a lot of open source VR goggles around there. However, most of them just uses a cellphone as a screen. I only found this link on "Instructables" where they use a Raspberry Pi and a LCD screen to make one.

    Anyway, since it will be a rigid full-body suit, it doesn't need a really complex VR goggles system; After all, you won't have any room to move your head. So no need to put a tracker on there (I think/hope).

    So my idea would be to use those homemade holo-goggles, they normally use cellphones too, but maybe they can allow for a higher definition than VR goggles. Just hear me out:

    "Holographic" goggles are simply a reflection of light on a transparent film instead of individual pixels on a screen, you've probably already saw those "holographic" apps reflecting on transparent "cubes":

    They aren't holograms like those seen in science fiction (those would be considered "volumetric displays"), but they are interesting enough.
    The funny thing is that you can use that to make holographic lenses; Those "smart glasses" use this exact technology to make information visible for the user. Just think of it as a "projector" reflecting light on something.

    And yes, there are Open Source Arduino smart glasses around the web:

    The google "HoloLens" literally uses this to make its holographic glasses:

    And obviously, some cheap VR goggles use this same technology to deliver some good enough quality:

    And you can 3D print it:

    I also found this video about a project that tries to minimise the size of VR goggles in general, not that it fits my idea, but I think it could be useful anyway.

    And some time ago I found this display concept/product called "Looking Glass", that is basically a normal display that uses a lot of layers of "lenticular lenses sheets" to give the impression of a real hologram. The display shows the same image in 42 different angles one above other, so when it hits the different layers and different viewers, it shows the same image like it is a volumetric object.
    However, it needs a LOT of processing power, literally a dedicated PC gamer just to show a pre-processed image.

    Even though I don't intend to make something like this, this could be useful for someone and maybe for me.

    Anyway, what I wanted to say after all of this:

    You could use the Holographic goggles displays and the lenticular lenses sheets to give a higher definition and image quality, since you are not dependent on the electronic display size, but on its reflection (just like in the case of the smart glasses).

    You could use various (cheap) small displays reflecting their images on various layers of transparent plastic layers (that maybe could be made using Lenticular Lenses Sheets) to overlap different details of the same image.
    Yes, it would be bulky and need a lot of space,...

    Read more »

  • Project log 1: The "whats" and "whys" of this project

    FulanoDetail09/24/2022 at 22:31 0 comments

    Today is Saturday, 24 of September, 18:41 Brasilia Timezone

    I already have another project on hold because I couldn't afford it, not I'm literally making another project purely on impulse. I'm not just dumdum, I'm completely smooth brain.
    Spoiler: this is a bad idea.

    Again, I don't know anything about Virtual Reality Software and Hardware, and again I'm jumping on this project completely blind and completely stoopid.

    I had this idea a long time ago. I tried to make a gofundme so I could pay an engineer to make a glove for me, but no one gave a damn about the idea. Maybe that's a signal that I shouldn't be pursuing this idea...

    What is "Piezoelectric"?

    Well, if you just got into this project and is kinda lost on what the heck all those buzzwords mean, worry not, I will try to explain at the best of my abilities. Meaning: I'm going to let some videos on the subject to explain for me. lol

    In summary, piezoelectrics are coin-like crystals that vibrate when you pass a current through them, and the reverse is also applicable: if you vibrate/impact/press it, it will generate a electrical current. All of this in a single device.

    You can use this to either make a movement generator, or use these electrical currents to stipulate an amount of force.

    So if you move a leg to walk, but your leg is held in place by something (like an armature with piezo-sensors), you will just apply a pressure on the piezoeletric crystals; which, in turn, will create a certain amount of current, and thus, can be translated as a movement inside a virtual world.

    Let's say, your leg movement for walk generates 0.5 volts (it is a random number) when it applies pressure on the piezoelectric sensor, the computer can define that this 0.5 volts is a X value of centimetres that your leg will move.

    What are "Haptics"?

    It is just tactile sensation, you can use the vibration to simulate the sensation of touch. Thus, haptical feedback. I doubt I will be able to simulate the sensation of cold and heat, but these can be arranged with the equally cheap (for north-americans) Peltier Thermoelectric Cooling Tablets used on computer cooling.

    Piezoelectrics are quite a versatile things for this, you can literally take a piezoelectric and depending on the vibration, you could simulate texture. In the video below, it is shown a product where some people used ultrasonic piezoelectric devices to simulate the sense of touch in middle air.
    Obviously, the version they used is much more potent than these cheap piezo ones, but since they will be practically touching your skin, I don't see why it wouldn't be able to do the same.

    Why a full-body rigid suit?

    Because I believe it will be easier and cheaper to construct something without moving parts, and it will be less physically intense to use such device; instead of awkward buttons on VR controllers, you will just feel everything on your skin, naturally interacting with it.

    Also, I say "rigid suit", but it will basically be a glorified armchair with a cover. And since this thing is completely DIY from scratch, it will probably look like scrap clumped together.

    Also, the biggest reasons are safety and complexity.

    If you made a full body VR suit using actuators (hydraulic, electric, pneumatic etc.), you would have to deal with two major factors: the movements of the user, and the movements the virtual ambient would employ in the user.

    A human being can easily exceed 80kg (176,37lbs) depending on a lot of factors, now imagine a machine built to sustain its weight, the force of the movements and the force it needs to carefully apply to the user limbs in other to simulate what it is happening inside the game?

    By the way, the lower part of the human body (thighs, legs and feet) has 3 times the strength necessary to lift the entire body weight. That's why you can still walk and run carrying weight.

    Below is the image of the "Holotron...

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