SoftBank Pepper: Known Problems & Fixes

RuntimeError: Invalid signature when subscribing to ALMemory events

Symptom

Calling `memory.subscriber('ALTouch/TouchChanged')` raises a `RuntimeError: Invalid signature` at runtime when connecting to the robot via libqi-python from a desktop machine. The error occurs on the fifth line of the subscription setup code.

Affected

NAOqi 2.5.8, libqi-python 3.0.0

Fix / Workaround

no confirmed fix

Bad magic number error prevents robot mesh installation in simulator

Symptom

Via the community softbankrobotics-research/qibullet driver: when running any test program, the Pepper virtual robot fails to spawn because `meshes_installer_27.pyc` raises `ImportError: Bad magic number in .pyc file`. Running the installer directly produces `RuntimeError: Bad magic number in .pyc file`, and no robot mesh is visible in the GUI.

Affected

qiBullet, Linux Mint 20, Kernel 5.4.0-52-generic, Python 2.7.18

Fix / Workaround

no confirmed fix

Segmentation fault in camera thread on macOS when running Pepper simulation

Symptom

Via the community softbankrobotics-research/qibullet driver: running any Pepper simulation test on macOS results in a fatal segmentation fault originating in the camera thread, specifically in `camera.py` at `_getCameraImage` and `_frameExtractionLoop`. The crash is triggered by calling `pepper.subscribeCamera()` and does not occur when camera subscription is omitted.

Affected

qiBullet 1.4.0, macOS Catalina 10.15.1, Python 2.7, pybullet 2.6.6

Fix / Workaround

no confirmed fix

ALTracker service missing on Pepper 2.9; raises 'Cannot find service' error

Symptom

Calling `app.session.service('ALTracker')` on a Pepper 2.9 robot raises `RuntimeError: Cannot find service 'ALTracker' in index`. The same code works on Pepper 2.5. The service no longer exists in the 2.9 software version.

Affected

Pepper 2.9, libqi-python

Fix / Workaround

Community members confirmed that ALTracker was removed in version 2.9 and suggested using the HumanAwareness service instead, including its `humansAround` property and connecting to it via `humansAround.connect()`.

Undefined symbol error when importing cross-compiled qi module on Pepper

Symptom

After cross-compiling libqi-python for Pepper and running on the robot, `import qi` fails with `ImportError: undefined symbol: _ZN2qi10Translator16setDefaultDomainERKNSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE`. The error occurs at runtime on the robot itself and is caused by `LD_LIBRARY_PATH` ordering loading the wrong `libqi.so`.

Affected

libqi-python, Python 3.8.12, GCC 10.3.0, Boost 1.71, ROS Noetic on Pepper

Fix / Workaround

Reporter resolved by placing the custom libqi build path before the ROS Noetic lib path in `LD_LIBRARY_PATH`: `export LD_LIBRARY_PATH=/home/nao/.local/bin/libqi/lib:/tmp/gentoo/opt/ros/noetic/lib`.

Pepper SDK emulator fails to start with invalid GPU mode error

Symptom

The Pepper SDK emulator stops working and throws the error: 'ERROR: Invalid GPU mode swiftshader_indirect, use one of: on off host guest angle angle9 mesa swiftshader'. Reinstalling the plugin does not resolve the issue. Switching graphics to Hardware starts the emulator but results in a white screen with no robot displayed.

Affected

Windows 10; Pepper Plugin (Android emulator version 29.0.11 or higher noted as related known issue)

Fix / Workaround

A workaround is documented at the official known issues page (https://qisdk.softbankrobotics.com/sdk/doc/pepper-sdk/ch5_news/known_issues.html), as acknowledged by a maintainer.

App non-functional due to permission denied creating qimessaging config directory

Symptom

After installing the app on Pepper, the app displays only its layout without functioning. The logcat shows: 'E/qi.path.sdklayout: Cannot create directory "/mnt/sdcard/.config/qimessaging" error was: boost::filesystem::create_directories: Permission denied: "/mnt/sdcard/.config"' and 'E/qi.os: Unable to create file: ""'. The permission error itself does not fully prevent operation; a separate issue (robot not being in awake/active state) was identified as the cause of non-functioning behaviour.

Affected

Qi SDK for Android; tested on virtual robot and physical Pepper

Fix / Workaround

A community reporter found that the permission error alone does not block operation. The robot must be in the awake (non-rest) state for robot focus to be gained; waking up Pepper resolved the non-functioning behaviour.

Explore behavior stops prematurely and produces a cut-off map

Symptom

When using the Explore behavior to map an environment, the exploration stops prematurely before the full area is scanned. The resulting map is cut off or cropped unexpectedly. In one instance the robot reported finishing exploration but had not visited all areas; in another it spent excessive time in a blocked corner.

Affected

NAOqi 2.5; naoqi_navigation_samples

Fix / Workaround

no confirmed fix

libqi-python connection to Pepper on NAOqi 2.9 fails with RuntimeError: disconnected

Symptom

When attempting to connect to a Pepper running NAOqi 2.9.5 using libqi-python, app.start() or session.connect() raises 'RuntimeError: disconnected'. The log shows: '[W] qi.FutureSync: Error in future on destruction: disconnected - continuing stack unwinding...'. Using tcp:// to connect to the robot's port 9503 causes the server to close the socket because that port expects TLS-encrypted connections.

Affected

Pepper 1.8; NAOqi 2.9.5.172; libqi-python 3.1.1 and 3.1.4; Python 3.10.12; Ubuntu 22.04.3 LTS

Fix / Workaround

A maintainer confirmed the fix: use 'tcps://' instead of 'tcp://' in the connection URL to match the TLS-encrypted endpoint on port 9503. This resolved the disconnection error for the reporter.

Binary audio buffer cannot be passed to sendRemoteBufferToOutput() via Java SDK

Symptom

When calling sendRemoteBufferToOutput() through the Java/jnaoqi API and passing a byte array, list of bytes, or ByteBuffer, the call fails with the error: "qimessaging.jni: Cannot serialize return value: Unable to convert JObject in AnyValue". An additional error "qimessaging.remoteobject: no promise found for req id:162 obj: 60 func: 2 type: Reply" was also observed when using the qimessaging API directly.

Affected

C++ SDK 2.5.5, jnaoqi

Fix / Workaround

Community suggestion: encode the raw audio data as a Base64 string, pass it to a simple intermediary service hosted on the robot (written in Python or C++), and have that service decode the string and call sendRemoteBufferToOutput() via the Python or C++ qimessaging API.

focus.take() raises RuntimeError when called from libqi-python on NAOqi 2.9

Symptom

When attempting to control a Pepper robot running NAOqi 2.9 via libqi-python, calling focus.take() raises a RuntimeError: "could not take the focus: focus is owned by another activity". This occurs even when the tablet has only the launcher open and no user activity is running, preventing the script from acquiring the focus needed to call services such as AutonomousAbilities.

Affected

NAOqi 2.9 (QiSDK), libqi-python

Fix / Workaround

no confirmed fix

Navigation explore app fails with 'No exploration loaded' when retrieving map

Symptom

When running the navigation samples explore app, the robot throws a RuntimeError: "ALNavigation::getMetricalMap No exploration loaded." The error occurs inside the Get map behavior box, indicating the robot has no map loaded when the retrieval is attempted.

Fix / Workaround

Community suggestion: after making maps with the explore app, use the 'places' app to load a map before attempting to retrieve it.

KneePitch joint overheats and triggers temperature warning during repeated maximum-speed movement

Symptom

When ALMotion.moveTo is executed repeatedly with both acceleration and plane speed set to the maximum value of 0.55, the robot's KneePitch joint overheats. The system log reports: "ALBodyTemperature: The KneePitch is hot. Temperature of KneePitch is: 80 degrees Celsius. Temperature status of KneePitch is: 1".

Fix / Workaround

no confirmed fix

Speech recognition and translation fail when project language set to German

Symptom

When running a Choregraphe project configured for English only, the robot logs two errors: "ALSignsAndFeedback: Cannot find service 'ALSignsAndFeedback' in index" and "behavior.translator: Fail to load translation for '...lastUploadedChoregrapheBehavior' lang 'de_DE'". Adding German in the project properties does not resolve the error.

Fix / Workaround

no confirmed fix