Raspberry Pi Object or specific tag sensor - linux

I am planning to work with a Rasberry Pi in order to try and detect motion of certain things. I was thinking of capturing motion with a similar approach RFID stickers perhaps placed on objects to detect their movement. Does anyone know of a type of sensor that could recognize specific movement or what technology I may look into ?

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Capture audio output from raspberry pi (for LEDs)

I have a Raspberry pi 4 and my goal is to connect it to some LEDs that will react to music that is playing through bluetooth (or AirPlay, ...). I've installed rpi audio receiver and so now I can stream music to it.
Now I need to write (or use some) code, that could parse what is being played to the audio output (via built-in 3.5mm jack), so the main question now is:
Is it better (or possible) to intercept the audio somewhere and analyse it with my own code, or does this require some deep modifications to the streaming program? Or do you know of a better solution that could point me to the right direction?
I saw a lot of people using an external mic, but the whole process is too different from mine.
Type of LED strip is not important right now, if I'm able to write my own code for it.
Thanks for any help!

Is it possible to stream video to raspberry pi from a webcam?

I am building a self driving car model using python(tensorflow). The architecture design of my project looks like the following. The CNN code will be in the raspberry pi, which is connected to a radio controller using wires from it's GPIO pins to send motion signals. The pi then controls the car. To "see" what's around it, the car uses a webcam that is mounted at the front center(this is the puzzle), which I wanted to stream the video to the pi; then the pi will use it's trained model(brain) to decide whether or not to move forward, make a left turn, a right turn and so on. The pi and rc radio controller are not mounted on the car, and I want them to remain that way for a reason. The car has the webcam and that is it. I am considering replacing the webcam with an android phone due to lack of alternatives, but I would hate to do that. If you would like more explanation on the structure of my project, please comment down there.
My question is how can I stream the video to my pi in real time?

Beacon/device that is able to receive signal from another beacon and pass it to smartphone

I've been searching in articles for some simple device that is able to do that(title), but I didnt find any. I am looking for a simple device that is able to get RSSI from some unique beacon in range and then pass it (reveiced RSSI value) to the smartphone(via bluetooth).
I thought about some "smart beacon" that is able to work bidirectional (Get signal from another beacon, then pass it to the smartphone). Has it ever been done?(If yes I would be grateful for any articles).
If I wouldn't find anything I will use another smartphone as that device.
I am unaware of any commercially available products that do this. A more common solution might be a device that scans for other beacons in the vicinity and reports them directly to a server.
The reason that reporting scanned beacons to a smartphone over BLE isn't a common solution is because it would be simpler for the phone to do the scanning itself. Why would you need a separate hardware device to do this?
Such a solution you propose might have the advantage of extending the range of the smartphone, but probably not by much. Consider that if the reliable range of BLE is 40 meters, then a phone 40 meters away from the device you suggest might be able to pick up beacons at most 80 meters away in the same direction. Practically speaking this would rarely even double the scan area covered by the phone simply working by itself.

Sending iBeacon signal strength(for distance) to arduino board

I have a project using quadcopter(ARDrone).
And i want to controlled it unmanned indoor, using arduino board and iBeacons.
iBeacons send signal strength and floor info to arduino board(inside ARDrone connected main board) and iphone for searching location in building. Project is just controlling drone to go to iphone's location by itself. All calculation parts are managed in server.(triangulation etc.)
Here are the questions.
How can arduino board receive bluetooth 4.0 signal and send it to
server? 4.0 signal can be received by bluetooth 2.0 module?
Do i need to build bluetooth 4.0 receiver module? Or are there any other ways?
In server, complicated calculation will be managed by programs in c++ language but simple things are handled by web language. php? jsp? or other lang which one is better?
and some hints for this project.
I really need your help. thanks;)
3. The calculations to identify the location from the received signal strength and location of the Beacons are fairly straightforward, so should be fine in which ever language you prefer. You will need to use Trilateration, once you have converted RSSI (received signal strength) into a distance.
4. The major challenge you will have is getting accurate distances, iBeacons as you know use Bluetooth LE, what you may not know is that this operates on a Microwave wavelength and so is easily disrupted by humidity in the air, as well as other objects like people. This means that the RSSI readings will jump about a bit, a basic way to overcome this is to take an average over several readings, even so the distances found will be rather inaccurate in many circumstances. To get an idea of the kind of readings that you will get for distance without compensating for environmental factors have a look at my presentation: "Factors effecting positional accuracy of iBeacons", that is based on Estimote iBeacons, but should be relevant for other brands as well, but you will need to do your own experiments to work out the relative errors. I was seeing distance readings that were +-2M away from the real location.
My name is Wojtek Borowicz, I'm a community evangelist at Estimote.
To add to what Chris Thomson (BTW, cool slide deck!) - your first two question can basically be reduced to a single answer: you need your receiver to support Bluetooth Smart on both the hardware and software side. So yes, you need a Bluetooth 4.0 module to receive Bluetooth 4.0 signal and you also need a Bluetooth 4.0 stack for your receiver to be able to 'interpret' that signal.

Touchscreen using sound input?

i don't really know if it is actually possible, but i believe that it can be made. How possible is it to make a program that recognizes different sound bouncing from the screen and turn it into a position that will obviously be later fed to the mouse.
I know that it sounds kind of dumb, but lately i've been noticing that a very dull, strong sound is made when touching the screen, and that sound varies when doing so at different positions. Probably the microphone "hears" differently because the screen acts as a drum with the casing. Anyways, what do you think, anyone has any experience programming with sound?
First of all most domestic touch screens work by detecting pressure based on a criss-cross mesh layer underneath the display layer.
However I have seen an example where a touch interface was interrogated onto a pane of glass, it used 4 microphones to determine the corners, when you tapped a certain part of the screen it measures the delay in the sound getting to each microphone, therefore allowing one to triangulate the touch.
This is the methodology you would use, you don't even need to set up the hardware to test it, you could throw up an interface in VB, when you click in a box it sends out a circular wave and just calculate using the times it takes to reach the 4 points where the pointer is.
EDIT
As nikie suggested, drag & drop, or any kind of gestures would be impossible using the microphone method, as the technique needs a wave of sound to detect the input.
http://computer.howstuffworks.com/question7161.htm
I don't know if this will get you far, but you can investigate the techniques used in MIDI drums for returning various nuances of play.

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