d4rken / myolib

Android Myo library with full data access and support for multiple Myos.

myolib

This is an Android library to communicate with Myo devices.

It was created for a research project at the mHealth - Uniklinik RWTH Aachen deparment. The projected required receiving sensor data (Gyro, Accl., EMG) from multiple Myo devices simultaneously, which was not possible at that time (August 2015) through the official Android SDK for Myo from Thalmic Labs.

Contributions are welcome. If you submit pull-requests please adhere to the projects current coding style. If you are using this library, i would love mention your project here, feel free to contact me.

Setup

Add it in your root build.gradle at the end of repositories:

allprojects {
    repositories {
        ...
        maven { url 'https://jitpack.io' }
    }
}

Include this in your apps build.gradle file:

dependencies {
        implementation 'com.github.d4rken:myolib:0.0.5'
}

Examples

Utilizing callbacks

MyoConnector connector = new MyoConnector(getContext());
connector.scan(5000, new MyoConnector.ScannerCallback() {
    @Override
    public void onScanFinished(List<Myo> myos) {
        Myo myo = myos.get(0);
        myo.connect();
        myo.writeUnlock(MyoCmds.UnlockType.HOLD, new Myo.MyoCommandCallback() {
            @Override
            public void onCommandDone(Myo myo, MyoMsg msg) {
                myo.writeVibrate(MyoCmds.VibrateType.LONG, null);
            }
        });
    }
});

Receiving sensor data

/**
 * ...
 */
Myo myo = myos.get(0);
myo.connect();
EmgProcessor emgProcessor = new EmgProcessor();
myo.addProcessor(emgProcessor);
emgProcessor.addListener(new EmgProcessor.EmgDataListener() {
    @Override
    public void onNewEmgData(EmgData emgData) {
        Log.i("EMG-Data", Arrays.toString(emgData.getData()));
    }
});

Advanced use

BaseMyo baseMyo = new BaseMyo(getContext(), bluetoothDevice);
baseMyo.connect();
ReadMsg readMsg = new ReadMsg(Battery.BATTERYLEVEL, new MyoMsg.Callback() {
    @Override
    public void onResult(MyoMsg msg) {
        byte[] result = ((ReadMsg) msg).getValue();
    }
});
baseMyo.submit(readMsg);

Advanced advanced use

BaseMyo baseMyo = new BaseMyo(getContext(), bluetoothDevice);
baseMyo.connect();
WriteMsg writeMsg = new WriteMsg(
        UUID.fromString("00001800-0000-1000-8000-00805f9b34fb"),
        UUID.fromString("00002A00-0000-1000-8000-00805f9b34fb"),
        null,
        new byte[]{ /*....*/},
        new MyoMsg.Callback() {
            @Override
            public void onResult(MyoMsg msg) {
                if(msg.getGattStatus() == BluetoothGatt.GATT_SUCCESS)
                    Log.i("MYOAPP", "Data written!");
            }
        }

);
baseMyo.submit(writeMsg);

Example app

License

This library is licensed under Apache 2.0, see LICENSE

If you use "Android Myo library by darken" for your publication, please cite the following publication:

• Kutafina E, Laukamp D, Jonas SM. Wearable Sensors in Medical Education: Supporting Hand Hygiene Training with a Forearm EMG. Stud Health Technol Inform. 2015;211:286-91.

myolib's Issues

emgdata convertion from byte to integer

According to code, https://github.com/d4rken/myolib/blob/master/myolib/src/main/java/eu/darken/myolib/processor/emg/EmgProcessor.java

When EMG data received from DataPacket,
the code in the line 30 and 35 (something like "packet.getData()[i] & 0xFF;") converts the signed data to unsigned int.

I think passing the EMG data as byte array is better since jave has byte as only signed one. 😃

EMG data

hello can i use specific EMG data to play a sound or present a picture
can you help me

no sensor data appears in the sample app

when the exampleapp find the myo, it shows the myo, battery and firmware version but no sensor data, can you help me in fixing that?

Value: null
Identifier: 0000180f-0000-1000-8000-00805f9b34fb:00002a19-0000-1000-8000-00805f9b34fb
05-08 16:07:35.481 9122-9413/eu.darken.myolib.exampleapp V/MyoLib:BaseMyo:CA:0C:05:1F:16:F6: Processed: d5060001-a904-deb9-4748-2c7f4a124842:d5060201-a904-deb9-4748-2c7f4a124842
05-08 16:07:35.487 9122-9122/eu.darken.myolib.exampleapp I/ViewRootImpl: ViewRoot's KeyEvent { action=ACTION_DOWN, keyCode=KEYCODE_BACK, scanCode=0, metaState=0, flags=0x48, repeatCount=0, eventTime=114433812, downTime=114433812, deviceId=-1, source=0x101 } to DecorView@5b47354[MainActivity]
05-08 16:07:35.538 9122-9138/eu.darken.myolib.exampleapp W/BluetoothGatt: onCharacteristicRead() - Device=CA:0C:05:1F:16:F6 handle=23 Status=0
05-08 16:07:35.539 9122-9138/eu.darken.myolib.exampleapp V/MyoLib:BaseMyo:CA:0C:05:1F:16:F6: rtt: 60ms | SUCCESS | ReadMsg

Thanks in advance.

Myo orientation on arm in ON_SYNCED callback

The classifier event myohw_classifier_event_arm_unsynced = 0x02 contains a rotation/orientation value of the Myo on the users arm.

It's not specified in the Myo Bluetooth protocol but in the debugger it can clearly be observed that the event contains byte[6] of data. The undocumented data is current "WarmUpState" and the previously mentioned rotation/orientation.

There is some more information in another Myo library project for OSX.
Here and here.

A comment there states:

/// Retrieve the estimated rotation of Myo on the user's arm after a sync.
/// The values specifies the rotation of the myo on the arm (0 - logo facing down, pi - logo facing up)

I did not get any meaningful values around 0 or pi during tests though.

Unknown Myo serial number format

The protocol specifies the serial number as byte[6].
I'm not sure how to format this to a serial number.
A hex string?

uint8_t serial_number[6]; ///< Unique serial number of this Myo.
https://github.com/thalmiclabs/myo-bluetooth/blob/master/myohw.h#L95

https://github.com/d4rken/myolib/blob/master/myolib/src/main/java/eu/darken/myolib/MyoInfo.java#L72

I tried straight conversion by new String(...) but the result was just a couple of unreadable characters.

Outdated dependencies

I am using the library but it works on API 23 or less
can you help me

MotionEvent - Unknown TAP direction value

The MotionEvent contains a tap direction parameter for which we currently don't know the expected values
While the tap count is likely just a number the tap_direction is probably an enum.

BluetoothDevice

In your description of Advance use, while trying to access the battery level, we must present the bluetooth device in constructor of BaseMyo. Can you please explain where can i get this BluetoothDevice?

BaseMyo baseMyo = new BaseMyo(getContext(), **bluetoothDevice**);
baseMyo.connect();
ReadMsg readMsg = new ReadMsg(Battery.BATTERYLEVEL, new MyoMsg.Callback() {
    @Override
    public void onResult(MyoMsg msg) {
        byte[] result = ((ReadMsg) msg).getValue();
    }
});
baseMyo.submit(readMsg);

No connection can be established

I made a simple android app, that uses your library and the code on the front page to get a Callback when the device is connected. Unfortunately, this never happens, the app does not find a myo device. It is powered on and also connected to the phone via bluetooth.
Any help would be greatly appreciated!