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Looking for a device that give maximum possible combination of:
Accelerometer
Gyroscope
Rotation matrix
Linear acceleration
Magnetic field
Rotation vector
Or any other sensor which gives any data about 3D orientation.
OR: Are there devices that embed InvenSense MotionFusion chips?
I'm looking for a device which is already available for sale on market, however any confirmed information about any upcoming devices will help as well.
Thanks.
A couple of Market apps, AndroSensor and Sensor List show actual phone sensors with running data. Good old Nexus One has Accelerometer and Magnetic compass. I assume you want a gyroscope.
My year-old AT&T Galaxy S has a couple of orientation sensors that may add-up to 6 axis but not a true gyro. A wealth of gyroscople links are documented on SO and more details on Galaxy S sensors here.
Max, let us know which device you settle on, please, and how it works out.
Apparently, Galaxy S2 has LOTS of sensors Orientation type of the sensor
My HTC Desire (aka the Nexus One) is an oldish device now and it has all the sensors needed to detect it's orientation in 3 dimensions (gyro) and movement therein (acceleration).
I suspect most phones have these sensors - they're commonly used in Apps and people tend not to use stuff which isn't widely available (like proper multitouch for example).
It must have some sort of light sensor as it has an automatic backlight adjustment too - tho I've never tried to access that for any development purpose.
In fact, those apps which demonstrate sensor values only show a blank against things like temperature sensors which I suspect few devices have!?
If you'd like me to check it for any other sensor value - let me know - but I've developed a few Apps which use those sensors widely so I know they do work...
Related
Can you work out if another iphone is say ~5 horizontal meters away?
This question has been asked here almost identically but a decade is a long time in tech. I have no interest in direction.
How to measure distance between two iphone devices using bluetooth?
Current solution attempts
GPS - This is too inaccurate for <10m
Bluetooth - iBeacon a potential solution for iphones. Similarly, may be too inaccurate due to BT signal interference. At least as SO claims 5 years ago. (How to measure the distance between an iPhone acting like an iBeacon and an Android device)
Have we made any progress here?
There have been no significant changes in the past 5 years. I wrote a blog post with a deep dive into the current state as of 2020. Mobile phones in 2020 have newer bluetooth chipsets than in 2015, and may support Bluetooth 5, but there are no significant new capabilities that improve the reliability distance estimates. Indeed, there are no new proximity sensors on iOS and Android phones (other than NFC, which only measures proximity of a few centimeters away), so it is inappropriate for this use case. What's more, 5 years has made things worse by adding fragmentation, especially on the iOS side. Back in 2015, there were only a few Apple handset variants in common circulation. Now there are over a dozen.
To recap the current state of affairs that is mostly unchanged: you can use one phone to transmit over BLE and another to measure the signal strength and estimate distance. For known transmitters and approximately line of sight conditions (e.g. phones are not in a pocket or purse) measuring whether two phones are 5 meters apart is possible with perhaps a 60 percent confidence interval. Where this falls apart is with three important variables:
Phones and especially Android phones are quite fragmented. Transmitter power and receiver sensitivity are quite unpredictable between models and have a large variance. Apple has much less variance between models, but you still see differences that noticeably affect results.
People often put phones in a case, a purse or a pocket. This throws things off considerably further.
When clear line of sight conditions are not present, results are unreliable as you have said.
Bluetooth 5.1 does offer Angle of Arrival and other features that may improve this, but as of October 2020, neither Android 11 nor iOS 14 support any of these features, making the features unusable with almost any mobile phone.
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I am newly started work on beacon. Can you tell me one things is it possible beacon detect from watch without phone? Which smart watch, its possible?
Apple Watch's watch OS doesn't expose the necessary iBeacon or Bluetooth LE APIs that'd allow it detect beacons without phone's assistance. The only way for now is to do the scanning on the iPhone, and relay the scan results to your Watch app.
Android Wear on the other hand exposes the same Bluetooth LE API that a regular Android does[1]. Which means that, if the watch itself supports BLE scanning (I'd assume most of them do), you can use the android.bluetooth.le API[2] to detect beacons without phone's assistance.
[1] Well, for most intents and purposes, Android Wear is just a regular Android.
[2] Or any beacon library that utilizes this API, so that you don't have to write all the beacon discovery and parsing yourself. Android Beacon Library is probably the most widely used one. Since you tagged your question estimote, I assume you have Estimote Beacons—if that's correct, then Estimote Android SDK should also work for you. Note: I haven't tested either of the SDKs with Android Wear, so can't confirm 100% they'll work.
I'm currently using Estimote Beacons with their SDK and an Android smartwatch to develop my app.
I had some issues with Android Wear, because the smartwatch reads the signal from the beacons every 5 seconds despite having set on my app much shorter intervals (on the smartphone I had no problem). In my case this represents a major problem.
I hope to have been helpful.
It is possible with Android Wear (with just some limitations) and turns out not possible with Apple Watch. See this experiment http://elekslabs.com/2015/09/nearables-wearables-connecting-beacons-with-smartwatches.html
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distance between android and iphone
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I know nexus 7's have bluetooth 4.0 but what I was wondering if you could use bluetooth 4.0 LE to calculate the distance between two devices? I want a very accurate distance calculator between two devices. I asked earlier about an android and an iphone but I am now only concerned with 2 android devices.
No. Bluetooth LE isn't some kind of magic hi-res GPS, it's basically just bluetooth data transfer using lower-powered transmitters.
Distance to the other device affects signal strength, but so do a bunch of other things. It's like trying to use a WiFi signal analyzer to measure the distance to a wifi hotspot. (Try it. You won't have much success!)
Look at the rather over-hyped Hone Keyfinder: The only thing it can tell you is if you're getting closer or further away from your keys. The keys don't know where the phone is, and the phone doesn't know where the keys are.
iBeacon works by having beacons at fixed lat/long, with a low-power transmitter. They broadcast their lat/long, so if you're in range of one, you know where you are. If you have enough beacons near you, you can triangulate based on relative signal strength. iOS devices acting as 'beacons' only makes sense if somehow they have better GPS coverage than you do.
I have been building on top of the iphone augmented reality framework found here
but sadly, on mobiles without gyro (namely the 3GS) it doesn't work (as it states.)
Does anyone know of a fix to make it work with the motion sensors and compass heading instead ? Or would anyone be so bounty-hungry to provide the codes to a such framework ?
I will need a way to either make the vectors work, and if it is not possible, I will need to push through and just use heading only.
CoreMotion do work in devices like 3GS. However, this Framework pARk is for devices with gyroscopes (Runtime Requirements: iPad 2 or iPhone 4 running iOS 5.0 or later)
Gyroscope is a fundamental piece of inertial navigation systems (INS) and thus without it you'll have a severe loss in precision.
Check the paper: "Usability of apple iPhones for inertial navigation systems" for a comparison of the performance of iPhone 3GS and iPhone 4. The author's conclusion is:
However, the tests show that even with the use of filters
it is challenging to build a precise INS using sensors from
common devices because of their inaccuracies and high
error rate. The results show that the iPhone 4 can provide
tolerable results for a short time, but then the deviation
becomes too high because of the error rate. Currently we are
implementing a multi-dimensional Kalman filter to examine
possible enhancements. Furthermore we try to improve the
system by using more sensors from the iPhone 4, e.g. light
sensors and camera.
I believe you should think your app to support only iPhone4 or newer.
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I am using software (DVR) that is meant to talk directly to an IP camera. I am trying to pass a h264 stream directly into it, but it does not work if I just throw a stream onto it.
Can you recommend any "spoofing" software to emulate an IP camera? For the sake of argument, we can say that the camera we want to emulate is Axis P3301.
Given that a lot of software out there can talk to IP cameras, is there a way to use something like vlc/ffmpeg to look like its an IP camera ?
Thanks.
Axis IP cameras provide video through RTSP. Any RTSP server can be used to spoof the video aspect of an IP camera.
Examples:
Streaming with VLC
Open VLC
Select Media > Stream
Select source media, then click "Stream"
Click "next" to confirm the source
Under "New Destination" select "RTSP"
Deselect "Activate Transcoding" (make sure your source is h264/aac)
Click Add.
Select port and path to mimick the camera. Port is usually 554 but path varies by camera model.
Click Stream
Now you can connect with your DVR software.
Note that Axis cameras also have APIs to pant/tilt/zoom and set options like resolution and bitrate. You won't be able to emulate that.
Another good option is the Axis SDK that's available as part of their Application Development Partner program. The SDK includes software that will mimic an Axis camera perfectly. To join you fill out some paperwork and talk to a representative, but there's no cost and if you're working with Axis there are a ton of benefits.
http://www.axis.com/partner/adp_program/index.htm
If you want to fully emulate an Axis camera, there is a free software provided by Axis which allows you to do it with all the functionalities. It is mandatory to have that camera just one time to create the virtual camera template.
Axis Virtual Camera Download