We present a high-performance capacitive accelerometer with a sub-µg noise limit and 1.2 kHz bandwidth for particle acceleration detection applications. The low noise of the accelerometer is achieved through a combination of device design optimization and operation under vacuum to reduce the effects of air damping.
View Article and Find Full Text PDFThis paper proposes a Takagi-Sugeno (TS) fuzzy sliding mode observer (SMO) for simultaneous actuator and sensor fault reconstruction in a class of nonlinear systems subjected to unknown disturbances. First, the nonlinear system is represented by a TS fuzzy model with immeasurable premise variables. By filtering the output of the TS fuzzy model, an augmented system whose actuator fault is a combination of the original actuator and sensor faults is constructed.
View Article and Find Full Text PDFIEEE Trans Syst Man Cybern B Cybern
December 2007
In master-slave teleoperation applications that deal with a delicate and sensitive environment, it is important to provide haptic feedback of slave/environment interactions to the user's hand as it improves task performance and teleoperation transparency (fidelity), which is the extent of telepresence of the remote environment available to the user through the master-slave system. For haptic teleoperation, in addition to a haptics-capable master interface, often one or more force sensors are also used, which warrant new bilateral control architectures while increasing the cost and the complexity of the teleoperation system. In this paper, we investigate the added benefits of using force sensors that measure hand/master and slave/environment interactions and of utilizing local feedback loops on the teleoperation transparency.
View Article and Find Full Text PDFConf Proc IEEE Eng Med Biol Soc
June 2007
Accurate needle insertion in soft, inhomogeneous tissue has been a major concern in several recent studies involving robot-assisted percutaneous therapies. In procedures that involve multiple needle insertions such as transrectal ultrasound guided prostate brachytherapy, it is important to reduce tissue deformation before puncture and during insertion. In order to reduce this deformation, we have studied the effect of different trajectories for a 2-DOF robot performing needle insertion in soft tissue.
View Article and Find Full Text PDFNeedle insertion in soft tissue has attracted considerable attention in recent years due to its application in minimally invasive percutaneous procedures such as biopsies and brachytherapy. This paper presents a survey of the current state of research on needle insertion in soft tissue. It examines the topic from several aspects, e.
View Article and Find Full Text PDFMinim Invasive Ther Allied Technol
December 2006
Accurate needle insertion into soft, inhomogeneous tissue is of practical interest because of its importance in percutaneous therapies. In procedures that involve multiple needle insertions such as transrectal ultrasound-guided prostate brachytherapy, it is important to reduce tissue deformation before puncture and during needle insertion. In order to reduce this deformation, we have studied the effect of different trajectories for a 2-DOF (degrees of freedom) robot performing needle insertion in soft tissue.
View Article and Find Full Text PDFIEEE Trans Syst Man Cybern B Cybern
December 2005
Most conventional motion planning algorithms that are based on the model of the environment cannot perform well when dealing with the navigation problem for real-world mobile robots where the environment is unknown and can change dynamically. In this paper, a layered goal-oriented motion planning strategy using fuzzy logic is developed for a mobile robot navigating in an unknown environment. The information about the global goal and the long-range sensory data are used by the first layer of the planner to produce an intermediate goal, referred to as the way-point, that gives a favorable direction in terms of seeking the goal within the detected area.
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