Recently, the development of minimally invasive surgery has led to the emergence of the new research area: minimally invasive vascular surgery simulation. The goal of the surgery simulation is to provide a new way to ...
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Recently, the development of minimally invasive surgery has led to the emergence of the new research area: minimally invasive vascular surgery simulation. The goal of the surgery simulation is to provide a new way to enable the trainees to obtain the core skills of the techniques. One of the key component of the simulation for core skills training in minimally invasive vascular surgery is how to develop 3D real-time computer-based virtual environments. In this paper, we present the virtual environments targeting to simulate the motion of a catheter/guide wire with complex 3D vascular models. Experimental results show that the 3D virtual environments are effective and promising.
The computer-aided surgical simulation aims to provide an economic tool of effectiveness and convenience for the training process. In building this simulation system, the construction of the virtual anatomic environme...
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The computer-aided surgical simulation aims to provide an economic tool of effectiveness and convenience for the training process. In building this simulation system, the construction of the virtual anatomic environment is one of the major tasks. It provides the virtual tools with the scenario in which they are manipulated by the trainee. In intravascular surgery simulation, the surface model of the blood vessels is the most important part of the virtual environment. In order to achieve better performances in the simulation of path planning and navigation, the surface model based on real patient's CTA data needs further process. We proposed in this paper an approach to extract the centerlines of each segment of the image-based surface model of the blood vessels. The surface model is firstly processed to check the connectivity of the consisting polygons in order to extract the largest connected region within the surface. Next, the resulting surface is smoothed by a windowed sinc function kernel with proper parameters. After the normal vectors of the smoothed surface are computed, the surface is subdivided and the centerlines of the surface model are computed by using the power crust algorithm. The experimental results show that the approach is capable of extracting the centerlines of the vessel model.
In this paper, the problem of parameter estimation is investigated for a class of discrete-time linear systems with missing outputs and outliers. It is assumed that the unknown parameters are constant and the evolutio...
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In this paper, the problem of parameter estimation is investigated for a class of discrete-time linear systems with missing outputs and outliers. It is assumed that the unknown parameters are constant and the evolution of the systems is subject to some unknown but bounded noises. To solve such a problem, a recursive algorithm based on set membership identification is proposed and employed. Besides, the data validation is processed and outliers are set aside. The effectiveness of the algorithm is verified by performing some numerical simulations.
Wireless networked controlsystems have gained significant popularity due to commissioning and maintenance *** there are various wireless communication protocols available to accomplish the control networks. Recently,...
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Wireless networked controlsystems have gained significant popularity due to commissioning and maintenance *** there are various wireless communication protocols available to accomplish the control networks. Recently, IEEE802.15.4e protocol for low latency deterministic network has been introduced that shows prominent theoretical characteristics under effective frequency planning to minimize mutual interference. Factory automation, highly exacting from low latency point of view, requires sensors refresh rate not more than of order 10 milliseconds. This new protocol meets such stringent requirement of industrial automation systems. In this paper, we compare the new protocol with its previous version and observe its suitability for industrial networked controlsystems as a communication protocol. We introduce different LLDN(low latency deterministic network) superframe configurations that show trade-offs among various network parameters. It gives an insight of relationship among various network parameters like sensors refresh rate, number of devices accommodated in network and data payload exchanged between coordinator and end devices with emphasis on different levels of security incorporated.
In this paper, we introduce a metric learning approach for the classification process in the recognition procedure for P300 waves in electroencephalographic (EEG) signals. We show that the accuracy of support machine ...
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ISBN:
(纸本)9781479946037
In this paper, we introduce a metric learning approach for the classification process in the recognition procedure for P300 waves in electroencephalographic (EEG) signals. We show that the accuracy of support machine vector (SVM) classification is significantly improved by learning a similarity metric from the training data instead of using the default Euclidean metric. The effectiveness of the algorithm is validated through experiments on the dataset II of the brain-computer interface (BCI) Competition III (P300 speller).
Formation control from optimal control strategy is derived based on the position estimation for second-order molded agents using only the relative *** the proposed strategy,agents can realize the convergence to the de...
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ISBN:
(纸本)9781479947249
Formation control from optimal control strategy is derived based on the position estimation for second-order molded agents using only the relative *** the proposed strategy,agents can realize the convergence to the desired formation configure if and only if the interaction graph for the agents has a spanning *** control input is added into the derived control strategy,with the help of detecting obstacles using the relative position and taking avoidance measures using the estimated position,it can also realize obstacle avoidance for agents between themselves.
This paper presents a novel five-phase double-stator permanent-magnet synchronous motor (DSPMSM). The motor is compacted with DSPMSM and fault-tolerant motor, so that the motor not only inherits the merits of double-s...
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This paper presents a novel five-phase double-stator permanent-magnet synchronous motor (DSPMSM). The motor is compacted with DSPMSM and fault-tolerant motor, so that the motor not only inherits the merits of double-stator which with high torque density and high utilization rate of the space, but also achieves fault tolerance. A new structure of the rotor is proposed for the DSPMSM. The DSPMSM proposed in the paper poses with high air-gap flux density, torque density and fault-tolerant capacity. control strategies and electromagnetic torque characteristics of the DSPMSM with completely loss of one and two phases are described. The fault-tolerant performance of the DSPMSM is analyzed by finite element method.
Haptic technology is highlighted in minimally invasive vascular surgery simulation. During the virtual reality-based surgery training, realistic haptic feedback can be provided by control devices to help enhance the s...
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ISBN:
(纸本)9781479939800
Haptic technology is highlighted in minimally invasive vascular surgery simulation. During the virtual reality-based surgery training, realistic haptic feedback can be provided by control devices to help enhance the surgeons' surgical performance. In this paper, we present a haptic rendering scheme for the vascular surgery simulation. The scheme consists of a self-designed haptic device, a physics-based resistance model and a virtual coupling network. The resistance model considers not only the contact forces between the vasculature and the beam element model of the guide wire but also the blood flow resistance. The virtual coupling network is applied to guarantee safety of the manipulation and stability of the simulation. Experimental results verified that the haptic force is close to reality and of good usability.
This paper presents a novel adaptive IIR filter modeling for the hysteresis characteristic in PEA (piezoelectric actuator). First, the PEA hysteresis operators are introduced and the modeling methods of traditional ad...
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This paper presents a novel adaptive IIR filter modeling for the hysteresis characteristic in PEA (piezoelectric actuator). First, the PEA hysteresis operators are introduced and the modeling methods of traditional adaptive IIR (infinite-impulse response) filter are discussed. Then, delay operators of IIR adaptive filter are replaced with Backlash operators to compose a new adaptive IIR filter model. During the modeling process, LMS (Least Mean Square) algorithm is used to adjust the weight values. At last the modeling effectiveness is verified via a micro-positioning system experiment platform based on PEA. Experimental results show that the proposed Backlash operator based IIR adaptive filter can achieve accurate hysteresis modeling.
In this paper, we develop a data-driven iterative adaptive dynamic programming algorithm to learn offline the approximate optimal control of unknown discrete-time nonlinear systems. We do not use a model network to id...
ISBN:
(纸本)9781479914821
In this paper, we develop a data-driven iterative adaptive dynamic programming algorithm to learn offline the approximate optimal control of unknown discrete-time nonlinear systems. We do not use a model network to identify the unknown system, but utilize the available offline data to learn the approximate optimal control directly. First, the data-driven iterative adaptive dynamic programming algorithm is presented with a convergence analysis. Then, the error bounds for this algorithm are provided considering the approximation errors of function approximation structures. To implement the developed algorithm, two neural networks are used to approximate the state-action value function and the control policy. Finally, two simulation examples are given to demonstrate the effectiveness of the developed algorithm.
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