something to indicate to the user how close (how high/low the RSSI is) you are to the beacon. /Mogens Does that really work? As I mentioned the two Bluetooth finder apps I tried seemed all but useless for locating Bluetooth devices. Maybe it would work better if there were some fixed beacons in kno...
I don't think ". I have no restrictions on that device." means "money no object". Still, this is cool if can afford it. Measure whatever you want. https://www.youtube.com/watch?v=KUdbrFOJlO0 Or https://www.youtube.com/watch?v=aq4NLmiJHwk I need to calculate distance between 2 spesific objects (Actu...
The big advantage of buying the beacon tags is that they integrate a battery into a neat case and last for a long time. Battery life is over 3 year on default setting. battery CR3032 battery https://www.banggood.com/Waterproof-BBeacon-Module-Module-Card-with-Eddystone-and-Beacon-for-Indoor-Navigatio...
Searching for "long range uhf rfid reader raspberry pi" gives a few results worth checking out. Nothing specific that might suit this application? There are things like this: https://www.amazon.co.uk/reader-vehicle-parking-application-meters/dp/B018EFLJJI which claim 3 to 5 metres reading range but...
Certainly that sort of 3D from stereo can be done.
As with any triangulation method the accuracy reduces as the separation reduces and the angle becomes very acute.
I think there's a tradeoff because wider separation improves the angle but also changes the view which can make feature matching harder.
If it has to be cheap you could try 2 cameras, probably usb so 2 will work on a pi, and determine the distances to the points, from the difference between the images after you have calibrated. You could then use my earlier method with measured angles. Good point. If two cameras are rigidly mounted ...
https://gaorfid.com/product/reader-active-usb-receiver-2-45-ghz-rfid/ 20m range used with active tags https://gaorfid.com/devices/rfid-tags-by-frequencies/active-2-45-ghz-rfid-tags/ Or something from eBay https://www.ebay.co.uk/itm/Active-RFID-Electronic-Tag-Reader-Undervoltage-reminder-ABS-For-Navi...
But the new BT5.1 is supposed to do this. Nordic's nRF52811 is one of the first chips, but I have yet to see usable positioning solutions for hackers. This could change any month or week. That's exciting tech. Sub 1m accuracy with direction and elevation. https://www.youtube.com/watch?v=c3XqbEKmNcM
Not surprisingly there are a lot of phone apps claiming to "locate your Bluetooth devices" I tried a couple but they don't seem effective. The reported signal strength doesn't vary with distance in a consistent way. I used a Bluetooth speaker that was not connected. That means it keeps advertising i...
You still haven't indicated what sort of accuracy you need for this measurement. That's critical.
The other key parameter is what distances you need to measure.
You can measure anything with triangulation, so long as you have at least one known distance.
Hello, Can I have different GPIOs working in parallel. For example can I have GPIO 17 -----> working as input GIPO 27 -----> working as input GPIO 22 -----> working as output at the same code? and nearly at the same time? You can certainly set au gpios as a mix of inputs and outputs. What do you me...
Thanks! Sounds good! So "open collector" is a term that refers to switching via (another) transistor? Not it means the collector of the output transistor is not tied to another transistor or a pullup to a voltage rail. That it is, the collector is free to float at any applied voltage when the trans...
Actually, its probably a reasonable assumption that the walls are vertical so a horizontal sweep of a distance sensor of any type could give you the walls and a range straight up could give the ceiling which gets you the corners. It all depends what accuracy is needed because walls aren't perfectly ...
Park a laser distance sensor on a tripod, adjust its tilt until the laser beam can be swung to hit the two corners. Measure the two distances and use the angle swung to calculate the distance between the two corners. I mentioned two types of laser distance sensor. True it would be a lot simpler to ...
Not a trivial problem. A level or higher mathematics would be useful to understand how these techniques work although you may get through treating libraries as black boxes that give you numbers. You would be relying a lot on examples though. You should start by defining what accuracy you need. Some ...
I'm waiting for someone to make a Bluetooth 5.1 diversity antenna Hat/module. Use RF module and the RSSI feature. Another way is RFID chips and RDF methods, low freq rf transmitter and directional coil antennas. You could put multiple USB BT adaptors on a Pi, arranging antennas in a wide triangle o...
I've done some testing with having 2 different HC-SR04, however I don't believe that this route will work, at least not with these specific modules. It seems that as soon as the module has received its echo, it stops listening for more echo's, which puts this part dead in its tracks. You don't have...
It sounds like you need battery power and small size. Maybe Pi ZeroW plus a USB power pack but maybe ESP32 or ATTiny which could run on a coin cell for a lot longer than the Pi. For sensing Bluetooth might be an easy option. You could read the RRSI signal strength of each Bluetooth or Wi-Fi device. ...
Only 1 project. That's not a constructive attitude. Like I said I'm new to using a pi. So what I'm asking might sound right out to lunch. You are intimidated by the task probably because you can't break it down into manageable chunks. That's sound engineering practice and good advice you don't seem...
So there are some multiple projects here: 1 add Bluetooth and MP3 functions to an old radio cassette (Pi or BT board audio out. Maybe mod radio for line in ) 2. Add some sort of digital remote controllable tuning mechanism to turn the analog dial of an old radio cassette (stepper motor drive) 3. Add...