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For the high precise tracking control purpose of a cable-driven manipulator under lumped uncertainties, a novel adaptive fractional-order nonsingular terminal sliding mode control scheme based on time delay estimation (TDE) is proposed and investigated in this paper. The proposed control scheme mainly has three elements, ie, a TDE element applied to properly compensate the lumped unknown dynamics of the system resulting in a fascinating model-free feature; a fractional-order nonsingular terminal sliding mode (FONTSM) surface element used to ensure high precision in the steady phase; and a combined reaching law with adaptive technique adopted to obtain fast convergence and high precision and chatter reduction under complex lumped disturbance. Stability of the closed-loop control system is analyzed with the Lyapunov stability theory. Comparative simulations and experiments were performed to demonstrate the effectiveness of our proposed control scheme using 2-DOF (degree of freedom) of a cable-driven manipulator named Polaris-I. Corresponding results show that our proposed method can ensure faster convergence, higher precision, and better robustness against complex lumped disturbance than the existing TDE-based FONTSM and continuous FONTSM control schemes. KEYWORDS adaptive control, cable-driven manipulator, fractional-order, nonsingular terminal sliding mode (NTSM), time delay estimation (TDE) 1396

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