This paper presents a methodology to create 3D visualization of discrete event simulation. This methodology connects discrete event simulation directly to 3D animation with its novel methods of analyzing and convertin...
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This paper presents a methodology to create 3D visualization of discrete event simulation. This methodology connects discrete event simulation directly to 3D animation with its novel methods of analyzing and converting discrete simulation results into animation events to trigger 3D animation. Discrete simulation results are analyzed and displayed in a graph structure that reveals all possible sequences of simulation events. In addition, a 3D animation framework is constructed for the visualization of discrete simulation results. This framework supports the reuse of both the existing 3D animation objects and behavior components, and allows the rapid development of new 3D animation objects by users with no special knowledge in computer graphics. This methodology has been implemented with the software component technology. Results in an electronics assembly factory are also provided in the paper to demonstrate the feasibility of this approach.
This paper presents the development of a full order sliding mode controller for tracking problem of direct drive robot manipulators. By treating the arm as an uncertain system represented by its nominal and bounded pa...
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This paper presents the development of a full order sliding mode controller for tracking problem of direct drive robot manipulators. By treating the arm as an uncertain system represented by its nominal and bounded parametric uncertainties, a new robust full order sliding mode tracking controller is derived such that the actual trajectory tracks the desired trajectory as closely as possible despite the nonlinearities and input couplings present in the system. A proportional-integral sliding surface is chosen to ensure the stability of overall dynamics during the entire period i.e. the reaching phase and the sliding phase. Application to a three DOF direct drive robot manipulator is considered.
Drive-by-wire is becoming a new technology in automobile replacing the current mechanically linked systems with electronic ones. Lately, it has attracted considerable attention, because of considerable advantages incl...
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Drive-by-wire is becoming a new technology in automobile replacing the current mechanically linked systems with electronic ones. Lately, it has attracted considerable attention, because of considerable advantages including safety, cost reduction, flexible interior design, reducing the weight and etc. With the ‘by-wire’ system, drivers could use different types of control devices in shape and function for the existing steering wheel and pedals, or even drive by one control device integrating the brake pedal, accelerator pedal and other functions. In this paper, a new drive-by-wire system is built by using the Electric Power Steering (EPS), Accelerator Pedal Module (APM) and a simple actuating mechanism for brake pedal. Especially, we concentrate on steer-by-wire system. To improve the accuracy and safety in steering, a new type of integrated reactive joystick and control algorithm is developed. The new joystick has larger displacement than general commercial joysticks and can generate the reactive force which promotes safe driving by preventing too fast steering. The new control scheme is one of the bilateral controls that stands on the base of the teleoperation control. Therefore, drivers could get more information about the status of car. The experiment is performed by a field test using a real car and shows the performance of this steer-by-wire system with control algorithm.
In this paper we describe the design and implementation of a nonlinear adaptive disturbance rejection approach for single-input-single-output linear-time-invariant uncertain systems subject to sinusoidal disturbances ...
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In this paper we describe the design and implementation of a nonlinear adaptive disturbance rejection approach for single-input-single-output linear-time-invariant uncertain systems subject to sinusoidal disturbances with unknown amplitude and frequency. This is an extension of our earlier study to a more complicated plant, a two-degrees-of-freedom (2DOF) system representing a vibration absorber setting. The controller design is based on a single Lyapunov function incorporating both the error states and the update laws and, hence, global stability and improved transient performance are readily achieved. Utilizing only the system output, a virtual control input is used in place of non-measurable and unknown signals. The performance of the adaptation algorithm is demonstrated through real-time simulations, both for regulation and tracking, on a 2DOF system representing an active vibration absorber setup. It is shown that when the primary system is subjected to an unknown sinusoidal disturbance, the proposed controller in the absorber subsection completely suppresses the primary system vibration in the presence of unknown disturbance.
Since teleoperation systems are mostly executed in the extreme environment, there are constraints in designing the mechanism and choosing sensors. This paper presents a novel quantitative comparison method of teleoper...
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Since teleoperation systems are mostly executed in the extreme environment, there are constraints in designing the mechanism and choosing sensors. This paper presents a novel quantitative comparison method of teleoperators based on H/sub /spl infin// framework. The upper H/sub /spl infin// norm bound of the system including H/sub /spl infin// sub optimal controller is used as the performance index. As a case study, the method is applied to a real teleoperation system to study the effects of sensory configuration and back-drivability of the mechanism on the performance of the system in tasks, which involve different environment impedances. It can be important criteria to design a teleoperator from the control point of view.
The paper addresses the problem of autonomous underwater vehicle (AUV) modeling and parameter estimation as a means to predict the expected dynamic performance of underwater vehicles and thus provide solid guidelines ...
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The paper addresses the problem of autonomous underwater vehicle (AUV) modeling and parameter estimation as a means to predict the expected dynamic performance of underwater vehicles and thus provide solid guidelines during their design phase. The use of analytical and semi-empirical (ASE) methods to predict the hydrodynamic derivatives of a large class of AUVs with conventional, streamlined bodies is discussed. An application is made to the estimation of the hydrodynamic derivatives of the MAYA AUV, an autonomous vehicle that is being developed under a joint Indian-Portuguese project. The estimates are used to predict the behavior of the vehicle in the vertical plane and to assess the impact of stern plane size on its expected performance.
This paper deals with the design of complex dynamic model of quadruped walking mobil robot. There is described the method of building of the numerical computational model and its simulating. Complex model consist of s...
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This paper deals with the design of complex dynamic model of quadruped walking mobil robot. There is described the method of building of the numerical computational model and its simulating. Complex model consist of submodels of robotic mechanism, DC motor, gearbox model and thermal model of electrical motor. Control algorithms are also considered in model. In the paper is also discussed application of computational model directly for control of robot and also as a data generator for global and local approximation method, mainly artificial neural networks.
The atomic force microscope (AFM) system has evolved into a useful tool for direct measurements of intermolecular forces with atomic-resolution characterization that can be employed in a broad spectrum of applications...
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The atomic force microscope (AFM) system has evolved into a useful tool for direct measurements of intermolecular forces with atomic-resolution characterization that can be employed in a broad spectrum of applications such as electronics, semi-conductors, materials, manufacturing, polymers, biological analysis, and biomaterials. The non-contact AFM offers unique advantages over other contemporary scanning probe techniques such as contact AFM and scanning tunneling microscopy. Current AFM imaging techniques are often based on a lumped-parameters model and ordinary differential equation (ODE) representation of the micro-cantilevers coupled with an ad-hoc method for atomic interaction force estimation (especially in non-contact mode). Since the magnitude of the interaction force lies within the range of nano-Newtons to pica-Newtons, precise estimation of the atomic force is crucial for accurate topographical imaging. In contrast to the previously utilized lumped modeling methods, this paper aims at improving current AFM measurement technique through developing a general distributed-parameters base modeling approach that reveals greater insight into the fundamental characteristics of the microcantilever-sample interaction. For this, the governing equations of motion are derived in the global coordinates via the Hamilton's Extended Principle. By properly selecting a set of general coordinates, the resulting non-homogenous boundary value problem is then converted to a homogenous one, and hence, analytically solvable. The AFM controller can then be designed based on the original infinite dimensional distributed-parameters system which, in turn, removes some of the disadvantages associated with the truncated-model base controllers such as control spillovers, residual oscillations and increased order of the control. Numerical simulations are provided to support these claims.
A translational cantilevered Euler-Bernoulli beam with tip mass dynamics at its free end is used to study the effect of several damping mechanisms on the stabilization of the beam displacement. Specifically, a Lyapuno...
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A translational cantilevered Euler-Bernoulli beam with tip mass dynamics at its free end is used to study the effect of several damping mechanisms on the stabilization of the beam displacement. Specifically, a Lyapunov-based controller utilizing a partial differential equation model of the translational beam is developed to exponentially stabilize the beam displacement while the beam support is regulated to a desired set-point position. Depending on the composition of the tip mass dynamics assumption (i.e. body-mass, point-mass, or massless), it is shown that proper combination of different damping mechanisms (i.e., strain-rate, structural, or viscous damping) guarantees exponential stability of the beam displacement. This novel Lyapunov-based approach, which is based on the energy dissipation mechanism in the beam, brings new dimensions to the stabilization problem of translational beams with tip mass dynamics. The stability analysis utilizes relatively simple mathematical tools to illustrate the exponential and asymptotic stability results. The numerical results are presented to show the effectiveness of the controller.
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