To know which USB devices are installed the following command can be used in a terminal: lsusb. The output of this command shows if the USB device is correctly connected and what the name of the device is. This command is a very good tool to find out if Ubuntu sees and recognizes the USB device.
It is possible that a hardware device cannot be detected by Linux or is detected, but not properly recognized by Linux. The device will be shown like this example: BUS 001 Device 002 ID 18a5:0216. By using the ID code, the full device name and type can be found on this site: http://www.linux-usb.org/usb.ids. When visiting this site, best to do is using the search function of the web browser. The ID code is a combination of two separate codes: a code for the device brand before the colon and a code for the device model after the colon. When searching on the website, select the ID code and enter this code in the search field of the browser.