Help and troubleshooting

eXperiBot cannot be switched on

• Charge your eXperiBot (see instructions for charging the eXperiBot).
• If your eXperiBot does not turn on after charging, please contact us directly.

eXperiBot does not respond to key presses and cannot be switched off

• The eXperiBot has crashed.
• Press the plus and minus buttons simultaneously for eight seconds to force it to switch off.

Module not recognized by eXperiBot

or Status LED of a module suddenly turns off

or Status LED of a module lights up or flashes red after the eXperiBot is switched on

• The connection to one or more modules is disrupted.
• Disconnect the module from your eXperiBot and then reconnect it.
• If the problem persists, please clean all the gold-colored contact points on your eXperiBot modules with a dry cloth.
• If the problem persists, there is probably a hardware error in one of your connected eXperiBot modules and the affected module will need to be replaced.

Status LED of a module lights up pink after the eXperiBot is switched on and the module no longer appears in the module list in the eXperiBot Manager

• The module must be restored by restoring the module in the app settings of the eXperiBot Blockly app.
• If the problem persists, there is probably a hardware fault and the affected module must be replaced.

Module does not move despite programming command

• Check whether the program is really running. You can tell whether a program is running by the white or light blue Status LED of the Powerbrain (see eXperiBot: Statuses and modes).
• If you use concurrent blocks, the program may end so quickly that you don't even realize it has started.
• Check your program code for possible errors.
• If the problem cannot be attributed to any of the above reasons, there is probably a hardware error and the affected module must be replaced.

The program is suddenly terminated, the eXperiBot beeps three times and the Status LED of the Powerbrain lights up red.

• An error occurred during program execution.
• Check your program code for possible errors. These include runtime errors, such as a zero division or incorrect handling of data types.
• If the problem persists, your program may be too large for the eXperiBot's memory. Try to reduce the size of your program (number of lines of code in the Python view).
• If the problem persists, it is likely that the memory is overloaded when the program is executed. Try to reduce the amount of data assigned to variables and the number of elements in lists.

eXperiBot suddenly behaves strangely while executing a program

• It is possible that the connection to one or more modules is faulty, so that the eXperiBot cannot receive or transmit data from or to certain modules (see Module not recognized by eXperiBot).
• If this is not the case and a Multisensor module is connected to the eXperiBot, there is probably a problem there (see Problems with Multisensor modules).

A color is not recognized at all or not correctly

• Adjust the sensitivity value in the programming block where color detection takes place.
• The sensor may not recognize the expected color of an object. Problems may arise especially when recognizing yellow, as the object may be perceived as white or green depending on the deviation in color tone.
• Ambient light can affect the color measurement. When using color measurement, avoid the influence of direct sunlight or strongly colored artificial light.

An object is unexpectedly recognized or not recognized

• Adjust the sensitivity value in the programming block where the object detection takes place.
• Objects are recognized by an infrared sensor and an infrared LED that shines on the object to be recognized. If the object to be recognized hardly reflects any infrared light, it is more difficult to recognize. White objects reflect a lot of infrared light, while black objects reflect little.
• If an object is unexpectedly recognized, make sure that no infrared LED from another Multisensor (possibly on another eXperiBot) or another infrared source is directed at the sensor.

A dark or light surface is unexpectedly recognized or not recognized

• The detection of dark/light surfaces, e.g. for a line-following algorithm, uses an infrared sensor and an infrared LED that illuminates the surface.
• Only deep black and non-glossy backgrounds are recognized as dark surfaces. Grayscales and colors, on the other hand, are perceived as light surfaces.

The distance value for an object in front of the Multisensor does not change

• In connection with the “Multisensor give distance to object” programming block:
  • the programming block is designed to detect objects within a range of 10 to 20 cm in front of the sensor
  • distances outside this range return the minimum or maximum value
• In connection with the “Multisensor give distance to object right/left” programming block:
  • the programming block is designed to detect objects in an area of 0 to 6 cm in front of the sensor
  • distances outside this range return the minimum or maximum value

The Status LED of the Multisensor turns off

• The Status LED of the Multisensor is switched off while a program is running and the Multisensor is taking measurements. The reason for this is that the color of the Status LED may distort the measurement. After the program has finished, the Status LED should light up again in the previous color.
• If the Status LED is still dark when no program is running, there is probably a contact problem (see Module not recognized by eXperiBot).

eXperiBot does not drive straight ahead, although the same speed was selected for the red and blue axles.

• The two motors of the motor module are not synchronized and can run at different speeds. Even small deviations can cause a significant left or right drift. You can correct this deviation by controlling the two axles at different speeds.
• When using the “Motor forward/backward” programming block, the direction of travel is automatically stabilized by the Powerbrain's gyroscope. Therefore, there is no deviation here. Unfortunately, it is not possible to automatically stabilize the direction of travel for the other programming blocks for technical reasons.

When turning or rotating, the angle achieved does not match the expected angle

• The gyroscope in Powerbrain is probably calibrated incorrectly. Calibration is done when the program starts. Try not to touch the Powerbrain during program startup. If you want to start the program by pressing the Play button, try not to move the eXperiBot when pressing the button.
• If the problem persists, there is probably a hardware error in the Powerbrain and it needs to be replaced.

Pivot or Twister module does not turn to the expected angle

• Pivot and Twister modules have a protection mechanism that switches off the module if it cannot reach the target angle after a few seconds. Make sure that the Pivot or Twister module can move freely.
• If the problem persists, there is probably a hardware fault in the affected module and the module will need to be replaced.

Grabber module does not open or close

• The Grabber module has a protection mechanism to ensure that the Grabber only opens or closes if the resistance is not too great. Make sure that the Grabber can move freely.
• If the problem persists, there is probably a hardware fault and the affected module must be replaced..

Module does not appear in the module list in eXperiBot Manager

• If the Status LED of the affected module is not lit, see Module not recognized by eXperiBot
• If the Status LED of the affected module is lit in pink, see Status LED of a module lights up in pink
• If the Status LED of the affected module is lit in red, see Status LED of a module lights up in red
• If the Status LED of the affected module is lit in a different color, please restart your eXperiBot and the app and check whether the module now appears in the eXperiBot Manager.

All workspaces and projects have disappeared

• It is possible that the app can no longer access the working directory because it has been moved outside the app. To change the working directory, use the “Change working directory” function in the app settings.

The app cannot be opened in the web browser

• Please make sure that your web browser meets the requirements of eXperiBot Blockly.
• If the problem persists, please contact us directly.

After starting the app, only a white screen is displayed

• Please make sure that your web browser or device meets the requirements of eXperiBot Blockly.
• If the problem persists, please contact us directly.

Warning “This block is no longer supported!” on blocks in the block editor

• Because we regularly improve the user-friendliness and functionality of blocks in the block editor, it is sometimes necessary to replace existing blocks with a new version.
• For blocks with the warning “This block is no longer supported!”, a new version is usually available, which you can find in the toolbox.
• You should replace or remove blocks with this warning as soon as possible to ensure that your program will continue to work in the future.