Eric
Do not send private messages with technical questions; they will be discarded. All technical questions must be posted publicly on the forum.
About
- Username
- Eric
- Joined
- Visits
- 9,275
- Last Active
- Roles
- Administrator
Comments
-
There some Linux support through community provided efforts. https://github.com/mbientlab/pymetawear https://github.com/brainexe/node-metawear
-
Metawear CPro boards do not have that much flash memory; if sampling at 800Hz, you can only log data for ~5s. If you want to record for longer periods at 800Hz, you will need to use a MetaMotion board. Most acceleration data will be correctly spa…
-
It is not recommended to use a LiPo rechargeable battery with the CPro as there is no protection circuitry on the C boards. If you need a MetaWear board with a rechargeable battery, then pick up a R variant instead.
-
https://mbientlab.com/csdocs/0/advanced_features.html
-
You can attach a 4pin debug header to the back of the board. If you are writing your own firmware, you can have the board analyze and post process the data and advertise as a BLE midi device. Alternatively, if you are writing your own companion a…
-
I'd count the number of samples received. For example, if you're sampling magnetometer at 10Hz and acc/gyro at 50Hz, then match every 5th acc/gyro sample.
-
The problem here is that you are assuming ReadValue has been assigned a value by the time the readReg function is completed. Your function should not return until it has received the result of mbl_mw_datasignal_read_with_parameters.
-
Apps, code, documentation, etc are linked in the first post
-
NDoF mode incorporates magnetometer data into the computation; try using IMUPlus mode instead.
-
Max is slightly under 525k total data samples for either acc or gyro, halve that if recording both which amounts to about a ~350 minutes log time for both acc & gyro 12.5Hz. You will have to contact MbientLab directly for custom hardware des…
-
This demo app streams quaternion data to a rotating cube app. https://github.com/mbientlab/MetaWear-Tutorial-Android/tree/master/sensorfusion The sensor fusion algorithm outputs both linear acceleration and quaternion data.
-
No, it depends on the bluetooth connection parameters, which it seems the creator's update increased the default connection interval.
-
What is wrong with the current code? What is the expected behavior vs. what is actually happening?
-
Use the MetaBase app for data logging.https://itunes.apple.com/us/app/metabase/id1088416232?mt=8
-
The sensor fusion algorithm describes device orientation. What configuration values are you using and can you post quaternion data that showcases the issue you are describing?
-
Increase the time for response to 1000ms (1s). mbl_mw_metawearboard_set_time_for_response
-
Does this behavior occur if you use the other data range? Does updating the firmware resolve the issue?
-
The GATT services / characteristics cannot be modified with the stock firmware. MetaMotionR boards come with a 6-axis IMU and magnetometer. You will have to analyze the data to characterize strikes and orientation. What exactly are you debu…
-
What I mean is the exact motions you are doing.
-
How are you rotating the board? Are the boards near any external magnetic fields?
-
So, streaming euler angles or linear acceleration is completely fine? What if you reduced the accelerometer range to 8g, down from 16g?
-
This appears to be an issue with your Bluetooth adapter, driver, or OS; setting the time for response to 4s should be plenty of time to go through the initialization process. If you are up for further debugging, log the values of the writeCharacte…
-
An 800Hz data sample produces data faster than the time granularity of the logger. You should instead divide the total number of samples received by the elapsed time and see if that matches your selected sampling frequency.
-
It's possible the addRouteAsync was failing so no loggers were actually created; you should always have error handling in your Continuations. What do you mean by "when logging is complete"?
-
The stack trace says you are losing bluetooth connection during the download. Make sure your board has adequate power and is close to your Android device while downloading. Was logging working fine before switching the API?
-
It's possible you aren't exactly replicating the same motion for both boards. Also, streaming accelerometer while running the step detector is not recommended. Disable the stream and see if that resolves the issue on the RG. Lastly, try using …
-
And how did you attach these magnets? With some tape?
-
If you use the same start/stop setup with just raw accelerometer or gyro data, does the same behavior occur? What about using other sensor fusion outputs?
-
The time processor delivers the current value at each interval; the data that lays in-between intervals is discarded.