Browsing by Subject "Manipulators"
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Item Open Access Design of a novel MRI compatible manipulator for image guided prostate interventions(IEEE, 2005-02) Krieger, A.; Susil, R. C.; Ménard, C.; Coleman, J. A.; Fichtinger, G.; Atalar, Ergin; Whitcomb, L. L.This paper reports a novel remotely actuated manipulator for access to prostate tissue under magnetic resonance imaging guidance (APT-MRI) device, designed for use in a standard high-field MRI scanner. The device provides three-dimensional MRI guided needle placement with millimeter accuracy under physician control. Procedures enabled by this device include MRI guided needle biopsy, fiducial marker placements, and therapy delivery. Its compact size allows for use in both standard cylindrical and open configuration MRI scanners. Preliminary in vivo canine experiments and first clinical trials are reported.Item Open Access Network model approach to the analysis of multirigid-body systems(Kluwer Academic Publishers, 1993) Tokad, Y.The mathematical model of a rigid body in three dimensional motion developed in [1] is used to formulate the equations of motion for the systems of rigid bodies connected to form a special type of open kinematic chain. In this interconnection pattern of rigid bodies, each rigid body is considered as a 3-port component, and for the sake of generality, initially no constraints are imposed on the joints used to interconnect the rigid bodies. The system is considered as an (m+1)-port component and the corresponding terminal equations are obtained in closed form. As an appliction of these equations, a three-link plane manipulator is considered. © 1993 Kluwer Academic Publishers.Item Open Access Robust antiwindup compensation for high-precision tracking of a piezoelectric nanostage(Institute of Electrical and Electronics Engineers Inc., 2016) Liu, P.; Yan, P.; Zhang Z.; Özbay, HitayUltrahigh-precision tracking in nanomanipulations poses major challenges for mechanical design as well as servo control, due to the general confliction between the precision requirement and large stroke tracking. The situation is further complicated by input saturation, which is almost inevitable for microactuators. This paper presents a novel control architecture combining a parallel internal-model-based tracking design and a robust antiwindup control structure, such that asymptotic tracking can be achieved for nanoservo systems in the presence of saturation nonlinearity and model uncertainties. For the augmented system with internal-model dynamics, an I/O-based equivalent representation from control (free of saturation) to system output is derived by incorporating the dead-zone nonlinearity, saturation compensation blocks, as well internal-model units. The robustness condition on the saturation compensator is also derived based on the sector bound criterion and an H∞-optimal design is developed accordingly. The proposed robust antiwindup tracking control architecture is deployed on a customize-designed nanostage driven by a piezoelectric (PZT) actuator, where numerical simulations and real-time experiments demonstrate excellent tracking performance and saturation compensation capability, achieving tracking precision error less than 0.23%.