im fairly new to this thing and my grammar isnt good,but here we go.
Im planning to light up a clear casted figurine for my school project by using addressable rgb sk6812,its 2020 in size and pretty convenient for my figure since its fairly small (15cm) and kinda cramped. Im trying to light it up with some effect like a burst going on,please see my tinkercad pic,sorry its the easiest method i can do for now attached design
As you can see i try to spread the whole led in every limb,the no 1 (first to get the data in) led are placed on the chest and im thinking if i can just spread the data out line from led no 1 to the next led around it and so on would make a ripple/burst like effect,also sorry for the cramped cable since my sk6812 only had 4 pin instead of bigger old 6 neopixel on tinkercad so im making it as close as possible with my situation,will it work without any future problem? the thing gonna be on for 3 days straight,also the attiny is just an example,i'll use a 5-12v powered led strip controller for the real deal like this one BTF SP105E Bluetooth Controller that probably already have everything in check for powering the led (its phone controlled too!).
Do i need bypass capacitor for each of led? or any extra resistor? my friend said the controller are packed with so many pattern and could be so fast that he afraid the led lifespan would shortened,but since both of us are kinda new i would like to hear for some experienced people here.
Here's my tinkercad sketch link
Any help would be great! Thnak you.
Looks good!
You are supposed to have a capacitor at each LED to help smooth out voltage when it is turning on and off rapidly, but you might be able to get away with not using them if you have thick, short wires and/or you do not turn the LEDs on too brightly.
Also, the LED boards you show in the picture already have capacitors on them. If you are not using these boards, it is pretty easy to solder a capacitor directly onto each LED.
You do not need any resistors.
Related
I'm brand new here, and also to Lua, so please bear with me...
I'm building an Airport in Minecraft, with my kids. I'm an overachiever and a dreamer, and at some point, my brain decided it would be a FANTASTIC idea to add in a cosmetic element that I have absolutely NO idea how to do. Smart, right?!
See, I got it in my head that I want to have display screens in our Airport that show the flight information of incoming/outgoing flights. Fast forward to my discovery of the Opencomputers mod for Minecraft, a few hours of watching tutorials on how to operate it, and thus began my search for knowledge of that which is the Lua language. Fortunately, I have a wee bit of coding experience (thanks to my college days) and I picked up the very basic of the basics. (It seems similar to C.) I've gleaned just enough to accomplish the bigger part of my goal: I've managed to write the bare bones of the program I dreamed up, and it works...for the most part. (I still need to figure out some redundancies and such...all in good time.)
But...it's so very plain, and not fancy at all. It doesn't look even remotely like what I was picturing in my head, and this simply will not do. So now I am on a quest to discover how to format the output of my program and make it look fantastic...or at least, as close as I can get it to what was in my head. I have managed to figure out how to change the gpu screen colors (foreground, background) so that is why it's blue/white. But it's not quite what I wanted, and it resets if the system is turned off. My goal is to change the format of the program output itself, not just the Opencomputers screen block. I've googled this until I'm blue in the face, and I have pored over forums and code tutorials and the like...only to fail at finding the information I need. It's possible that I've passed up the answer, simply because I'm still very new to the language, but that's another good reason for me to be here, right?
And so, I turn to you, O Great Dwellers of the Interwebs, the Keepers of Vast Programming Knowledge, for assistance. Please, pretty please, help me make my program look awesome. My kids just may think I'm the coolest Mom on the planet, and that would be more than fantastic...Not to mention we'd have one kickass airport to play around in. :)
Here's what you'll probably want to know:
First, This pic is what I want, (on the left) and what I have (on the right).
And here is the code for my program: http://pastebin.com/60nPfpB8
I apologize up front for all of the noob mistakes that my code is more than likely riddled with. I haven't figured out yet how to make the functions repeat themselves, or a good way to utilize a 24 hour clock for the "time" function. So any suggestions there would be welcome as well.
Thank you for taking the time to read, and I appreciate any help I can get with this. :)
I brought an HC-05 module. I used it twice or three times, it was working correctly, but now it is not blinking, can any one tell me what the problem is?
Bad or defected item, it happens often.
Maybe the electric power was no stable... or try it on another 8051 micro controller.
But if it blink that mean it's receiving power .. if not, buy another one:
http://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20160518055547&SearchText=HC-05+module
I've got a little side project going on using SDL2/SDL_mixer and a couple other sound libraries. I've been trying for a while now to synchronize my audio and video but haven't been able to get it anywhere near successfully. All new to this stuff so forgive the poorman's logic and coding. At first I thought to set the delay to SDL_Delay(30) after every frame, and then a few other numbers in that range. Not quite right. Then I tried doing it by getting Ticks. Where I would get the difference between current_ticks and last_ticks and set a delay if the delta between ticks was <=30 and set the delay to 30-delta. Still not quite right (by far). Hoping someone on here with more experience might guide me in the right direction. In regards to the video, it's a visualizer of course, seems like a popular beginners project.
The basic way you synchronize audio and video is that you choose one to use as a timer source and present the other according to that timer. The easiest is generally audio, but because it's generally buffered ahead, you need some method of measuring what time in the audio stream is actually coming out of the speakers. Once you get that, it's just a matter of waiting until the audio reaches the right time for the next video frame and displaying it.
Till now I have been able to create an application where the Kinect sensor is at one place. I have used speech recognition EmguCV (open cv) and Aforge.NET to help me process an image, learn and recognize objects. It all works fine but there is always scope for improvement and I am posing some problems: [Ignore the first three I want the answer for the fourth]
The frame rate is horrible. Its like 5 fps even though it should be like 30 fps. (This is WITHOUT all the processing) My application is running fine, it gets color as well as depth frames from the camera and displays it. Still the frame rate is bad. The samples run awesome, around 25 fps. Even though I ran the exact same code from the samples it wont just budge. :-( [There is no need for code, please tell me the possible problems.]
I would like to create a little robot on which the kinect and my laptop will be mounted on. I tried using the Mindstorms Kit but the lowtorque motors dont do the trick. Please tell me how will I achieve this.
How do I supply power on board? I know that the Kinect uses 12 volts for the motor. But it gets that from an AC adapter. [I would not like to cut my cable and replace it with a 12 volt battery]
The biggest question: How in this world will it navigate. I have done A* and flood-fill algorithms. I read this paper like a thousand times and I got nothing. I have the navigation algorithm in my mind but how on earth will it localize itself? [It should not use GPS or any kind of other sensors, just its eyes i.e. the Kinect]
Helping me will be Awesome. I am a newbie so please don't expect me to know everything. I have been up on the internet for 2 weeks with no luck.
Thanks A lot!
Localisation is a tricky task, as it depends on having prior knowledge of the environment in which your robot will be placed (i.e. a map of your house). While algorithms exist for simultaneous localisation and mapping, they tend to be domain-specific and as such not applicable to the general case of placing a robot in an arbitrary location and having it map its environment autonomously.
However, if your robot does have a rough (probabilistic) idea of what its environment looks like, Monte Carlo localisation is a good choice. On a high level, it goes something like:
Firstly, the robot should make a large number of random guesses (called particles) as to where it could possibly be within its known environment.
With each update from the sensor (i.e. after the robot has moved a short distance), it adjusts the probability that each of its random guesses is correct using a statistical model of its current sensor data. This can work especially well if the robot takes 360ยบ sensor measurements, but this is not completely necessary.
This lecture by Andrew Davison at Imperial College London gives a good overview of the mathematics involved. (The rest of the course will most likely be very interesting to you as well, given what you are trying to create). Good luck!
I'm looking for the most realistic way of playing sound of a rolling ball. Currently I'm using a Wav sample that I play over and over as long as the ball is moving - which just doesn't feel right.
I've been thinking about completely synthesizing the sound, which I know very little about (almost nothing), I'd be grateful for any tutorials/research materials/samples concerning synthesis of sound of a ball made of particular material rolling on surface made of another material. Also if this idea is completely wrong, please suggest another way of doing this.
Thanks!
I would guess that you'll get the biggest bang for your buck by doing a dynamic frequency adjustment on the sound that makes the playback frequency proportional to the velocity of the ball. I don't know what type of sound library you use, but most will support some variant of this.
For example, in FMOD you could use the Channel::setFrequency method. Ideally, you would compute your desired playback frequency based on your WAV's original sample frequency (Fo), the ball's current velocity (Vc), and the ball's 'ideal' velocity at which the default WAV sounds right (Vi). Something generally like:
F = Fo * ( Vc / Vi )
This will tend to break down as the ball gets farther away from the 'ideal' velocity. You might want to have several different WAVs that are appropriate for different speed ranges that you switch to at certain threshold velocities. Within each WAV's bracket, you'd do the same kind of frequency adjustment.
Another note: this is probably not something that is worth doing every frame. I'd guess that doing this more than 20 times per second would be a waste of time.
ADDENDUM: Playback frequency scaling like this can also be used for simulating the Doppler effect as well. Once you have your adjusted playback frequency, you'd perform another scale of the Frequency based on the velocity of the ball relative to the 'listener' (the camera).
Have you tried playing the sound forward, then playing it backward, and looping that? I use this trick graphically to creating repeating patterns. I don't know much about sound but it might work?
One approach might be to analyze the sound of a rolling ball, and decompose it into its component waveforms. Then you'd be able to generate your own wav file with synthesized waves.
You should be able to do this using an FFT on a sample of the sound.
One drawback is that the sound will likely sound synthesized - you'll have to add noise and such to make it sound more realistic. Getting it to sound real enough may be the hardest part.
I don't think you need the trouble to synthesize that. It would be way too hard to even sound convincing.
Depending on how your scene is, you could loop the sound foward/backwards and simulate a doppler effect applying a low pass filter and/or changing it's pitch.
By the way, freesoung.org is a great place for free samples. They are not professionally recorded but are a good starting point for manipulation. On the other hand, sound ideas has some great sample cds (they're actually industry standard) if you can find them on the cheap. You just have to search for which one has rolling ball sounds.
I really like the approach described in this SIGGRAPH paper:
http://www.cs.ubc.ca/~kvdoel/publications/foleyautomatic.pdf
It describes synthesizing the sound of a rock rolling in a wok (no, really :). The idea is to use modal synthesis (i.e. convolved impulse responses), and the results can be very convincing.
Here's a link to the video demo that goes with the paper:
http://www.cs.ubc.ca/~kvdoel/publications/foleyautomatic.mpeg
And here's a link to the JASS library (written by one of the authors), which was used to create the sound for the video:
http://www.cs.ubc.ca/~kvdoel/jass/jass.html
I'm not sure if you could make it run on a smart phone, but with an efficient enough convolution routine/approximation you might be able to do something interesting...
My question is 'why?' - do you see some benefit in this, or is it just for fun? Your question implies that you aren't happy with the wav you are using but I strongly believe that synthesising your own is going to sound far inferior.
If your wav sample doesn't sound right, I'd suggest try to find another sample. Synthesising a sound is not easy and is never going to sound as realistic as your sample.
Real time synthesis may require more resources for processing and computation. You may very well end up prerendering your synthesised sound into a wav file and performing a playback.
If you want to simulate the sound of different materials then you can use some DSP, or even simple tricks like slowing or speeding the wav playback. The simplest way is the prerender these in another application and store one copy of the file for each use.