dˈɪfɪkˌʌlti ɪn fˈaɪndɪŋ ðə ɹˈaɪt wˈeɪɾɪŋ fˈæktɚz lˈɪmɪts ðɪ ˌæplɪkˈeɪʃən ʌvðɪ ˌɛlkjˌuːˈɑːɹ bˈeɪst kəntɹˈoʊlɚ sˈɪnθəsˌɪs.
Difficulty in finding the right weighting factors limits the application of the LQR based controller synthesis.