TY - JOUR N2 - The paper describes a nonlinear controller design technique applied to a servo drive in the presence of hard state constraints. The approach presented is based on nonlinear state-space transformation and adaptive backstepping. It allows us to impose hard constraints on the state variables directly and to achieve asymptotic tracking of any reference trajectory inside the constraints, despite unknown plant parameters. Two control schemes (with and without integral action) are derived, investigated and then compared. Several examples demonstrate the main features of the design procedure and prove that it may be applied in case of motion control problems in electric drive automation. L1 - http://www.czasopisma.pan.pl/Content/117686/PDF/02_D963-971_01562_Bpast.No.68-5_30.10.20_.pdf L2 - http://www.czasopisma.pan.pl/Content/117686 PY - 2020 IS - No. 5 (i.a. Special Section on Modern control of drives and power converters) EP - 971 DO - 10.24425/bpasts.2020.134653 KW - motion control KW - nonlinear control KW - adaptive control KW - state constraints A1 - Kabziński, J. A1 - Mosiołek, P. VL - 68 DA - 31.10.2020 T1 - Adaptive, nonlinear state transformation-based control of motion in presence of hard constraints SP - 963 UR - http://www.czasopisma.pan.pl/dlibra/publication/edition/117686 T2 - Bulletin of the Polish Academy of Sciences Technical Sciences ER -