This is a selection of typical problems. If your problem is not listed below, please check the issues for all related repositories:

Could not connect to the myo motor: device not opened

There are a number of possible reasons:

You do not have read/write access to the device /dev/ttyUSBn. Where n is a number

Verify this by running:

cat /dev/ttyUSBn
  • If you get a ‘device not found’ you didn’t replace the right number for n in ttyUSBn
  • If you do not get anything, just a clean return you have correct access rights. Press Ctrl+C and find the problem elsewhere.
  • If you get a ‘permission denied’ then you have verified this problem. Add yourself to the ‘dialout’ group as described here: Allow your user to access the serial device.

The configured serial number does not match the serial number of the USB2FlexRay adapter

Go and double check it by following the instructions here: Configure the myo_blink software example.

You did not install the dependencies of flexrayusbinterface

Go and do it. No harm in doing it twice.: Install flexrayusbinterface

You did not install the udev rules

  • Check if there is a file called ‘30-ftdi.rules’ in ‘/etc/udev/rules.d/’:

    ls -alh /etc/udev/rules.d
    # if you don't get back anything try it with sudo:
    # sudo ls -alh /etc/udev/rules.d
  • The file should contain a line with something like this at the end:

  • If it does, compare it with the file supplied by ‘flexrayusbinterface’. It is located at:

    roscd flexrayusbinterface/udev
  • If they match, there might be something wrong with these rules for your system. Try the option below.

Something in the udev rules is not right

  • Manually try to unload the ftdi_sio and usbserial kernel modules as described in the Manually unloading ftdi_sio and usbserial and try the roslaunch command again
  • If that does help, use the manually loading as a workaround. Research udev files and how do unload kernel modules. If you are stuck or found a better solution, please create an issue on github at: flexrayusbinterface
  • If that does not help find the problem somewhere else. Have you checked your permissions as in the first step?