Top PDF Localization of Leader-Follower Robot Using Extended Kalman Filter

Localization of Leader-Follower Robot Using  Extended Kalman Filter

Localization of Leader-Follower Robot Using Extended Kalman Filter

Non-holonomic leader-follower robot must be capable to find its own position in order to be able to navigate autonomously in the environment this problem is known as localization. A common way to estimate the robot pose by using odometer. However, odometry measurement may cause inaccurate result due to the wheel slippage or other small noise sources. In this research, the Extended Kalman Filter (EKF) is proposed to minimize the error or the inaccuracy caused by the odometry measurement. The EKF algorithm works by fusing odometry and landmark information to produce a better estimation. A better estimation acknowledged whenever the estimated position lies close to the actual path, which represents a system without noise. Another experiment is conducted to observe the influence of numbers of landmark to the estimated position. The results show that the EKF technique is effective to estimate the leader pose and orientation pose with small error and the follower has the ability traverse close to leader based-on the actual path.
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Computational cost analysis of extended kalman filter in simultaneous 
		localization and mapping (EKF SLAM) problem for autonomous vehicle

Computational cost analysis of extended kalman filter in simultaneous localization and mapping (EKF SLAM) problem for autonomous vehicle

Extended Kalman filter (EKF) based solution is one of the most popular techniques for solving simultaneous localization and mapping (SLAM) problem. However, previous research showed the implementation of EKF for SLAM suffered with high computational costs, which affect the performance in real time application. This paper investigates the computational cost performance of an EKF-SLAM algorithm. The analysis was done by time measurement on sub-step motion update and measurement update on EKF by considering the total numbers of landmarks and numerous setting on range observation distance. The analytical results show that as the number of landmarks or range observation distances increased, the computational cost in measurement update step required more computation time compare to motion update step. Furthermore, improvements are needed to optimize the computational cost for the update step.
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Comparison of the Extended Kalman Filter and the Unscented Kalman Filter for Magnetocardiography activation time imaging

Comparison of the Extended Kalman Filter and the Unscented Kalman Filter for Magnetocardiography activation time imaging

Abstract. The non-invasive and radiation-free imaging of the electrical activity of the heart with Electrocardiogra- phy (ECG) or Magnetocardiography (MCG) can be help- ful for physicians for instance in the localization of the ori- gin of cardiac arrhythmia. In this paper we compare two Kalman Filter algorithms for the solution of a nonlinear state-space model and for the subsequent imaging of the activation/depolarization times of the heart muscle: the Ex- tended Kalman Filter (EKF) and the Unscented Kalman Fil- ter (UKF). The algorithms are compared for simulations of a (6 × 6) magnetometer array, a torso model with piecewise homogeneous conductivities, 946 current dipoles located in a small part of the heart (apex), and several noise levels. It is found that for all tested noise levels the convergence of the activation times is faster for the UKF.
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Drift correction using a multi rate extended Kalman filter

Drift correction using a multi rate extended Kalman filter

Extensions to visual odometry are SLAM (Simultaneous localization and mapping) and PTAM (Parallel tracking and mapping) [JTD14]. SLAM and PTAM use visual odometry techniques to calculate the relative motion but at the same time also maps the environment simultaneously (or parallel). The additional information the map provides can then be used to help with the drift. The map also helps the system to be able to recover fast when it loses track of its pose, for example when movement between two frames is large enough that little to no features of the previous frame are visible in the new frame. If the new frame does contain features which are already mapped before, it should be able to recover relatively fast. It should be noted that during the map generation drift is still present.
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A Solution to Partial Observability in Extended Kalman Filter Mobile Robot Navigation

A Solution to Partial Observability in Extended Kalman Filter Mobile Robot Navigation

Mobile robot navigation is one of the fascinating research which supports a truly autonomous mobile robot behavior. It is one of the aspects that really means in nowadays applications especially when a robot needs to perform a task to replace human operation. Robot has been known to functionally works in explorations, underwater navigation, mining and military by performing different kind of tasks. Depends on the applications, the mobile robot may require several conditions to be satisfied about its design and specifications. In navigation, one of its challenges is known as Simultaneous Localization and Mapping problem where mobile robot has to identify its location with reference to any of landmarks being observed and at the same time building a map based on its observations. This problem addressed several issues to be solved such as operating in dynamic environment, computational cost, uncertainties and data association [1]-[2].
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Analysis of robot localisation performance based on Extended Kalman Filter

Analysis of robot localisation performance based on Extended Kalman Filter

[21] used EKF SLAM and Fast SLAM to introduce a probabilistic approach to a SLAM problem under Gaussian and non Gaussian conditions. They presented the navigation of an autonomous robot using Simultaneous Localization and Mapping (SLAM) in outdoor environments. Fast SLAM is an algorithm that used Rao- Blackwellised method for particle filtering, estimated the path of robot while the landmarks positions which were mutually independent and with no correlation, can be estimated by EKF. Hence, a real outdoor autonomous robot was presented and several experiments had been performed based on both methods. The disadvantages were no correlation between any pairs of landmarks in the map, while landmarks in this network were mutually independent. Figs. 2.9 and 2.10 show vehicle coordinate system and estimation of the trajectory using EKF with Gaussian implication.
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Localization of passive UHF RFID Labels with Kalman Filter

Localization of passive UHF RFID Labels with Kalman Filter

Abstract. Localization via Radio Frequency Identification (RFID) is frequently used in different applications nowadays. It has the advantage that next to its ostensible purpose of identifying objects via their unique IDs it can simultaneously be used for the localization of these objects. In this work it is shown how Received Signal Strength Indicator (RSSI) mea- surements at different antennae of a passive UHF RFID label can be combined for localization. The localization is only done based on the RSSI measurements and a Kalman Filter (KF). Because of non-linearities in the measurement func- tion it is necessary to incorporate an Extended Kalman Filter (EKF) or an Unscented Kalman Filter (UKF) where simula- tions have shown that the UKF performs better than the EKF. Additionally to the selection of the filter there are different possibilities to increase the localization accuracy of the UKF: The advantages of using Reference Tags (RT) or more than one tag per trolley (relative positioning) in combination with an Unscented Kalman Filter are discussed and simulations results show that the localization error can be decreased sig- nificantly via these methods. Another possibility to increase the localization accuracy and in addition to achieve a more realistic simulation is the consideration of the angle between reader antenna and tag. Simulation results with the incor- poration of different numbers of fixed antennae lead to the conclusion that this is a useful surplus in the localization.
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Combined extended FIR/Kalman filtering for indoor robot localization via triangulation

Combined extended FIR/Kalman filtering for indoor robot localization via triangulation

In the three-node triangulation system, three angles are often measured between the robot heading and the direc- tions to the nodes. These angles are coupled with the robot plane coordinates and heading by nonlinear equations. The equations can be solved for unknown robot coordinates and heading. However, accuracy is commonly insufficient in noisy environments and optimal estimators are re- quired. The estimation theory offers several useful meth- ods to solve the triangulation problem. One of the most common approaches is the extended Kalman filter (EKF) proposed by Cox [14] and others. It suggests expanding the nonlinear functions to the first-order Taylor series and then using linear Kalman filtering. The EKF was used in tracking and robotics extensively [1–3,15,16] and has become a tool for moving vehicular navigation, tracking, localization, and self-localization [17,18]. The benefit of the EKF resides in the following facts:
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Video Detection and Tracking Using Extended Kalman Filter

Video Detection and Tracking Using Extended Kalman Filter

The proposed idea shows that automatically obtained person density estimates can be used to improve person localization and tracking performance in crowded scenes. It has formulated the person detection task as a minimization of a joint energy function incorporating scores of individual detections, pair-wise non-overlap constraints, and constraints imposed by the estimated person density over the scene, and also have demonstrated significant gains in detection and tracking performance on challenging videos of frames with varying density. Currently, video frames are processed individually and obtained detections are tracked in post-processing. There are hundreds of cameras deployed in public places (eg. Streets, shopping malls, airports). However, only a small fraction of the cameras outputs (<5%) is regularly observed by humans. Most of the video information is stored or destroyed without being watched or processed. This means that current surveillance systems are not able to detect abnormal events in real time. A large effort has been recently done to develop algorithms to track objects ( persons, vehicles) in video sequences and to recognize activities and unusual behaviours. In the future work the gradient based algorithm is used for activity based tracking which is more efficient than the other methods. In addition to this work a accuracy of the tracking can be calculated by using precision and recall factor.
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Particle / Kalman Filter for Efficient Robot Localization

Particle / Kalman Filter for Efficient Robot Localization

This paper presents a study for the effect of several filter approaches in the behavior of robot localizer using radio beacons that provide the ability to measure range only. Different filters namely Extended Kalman Filter (EKF), Particle Filter (PF) and a proposed Enhanced Particle/Kalman Filter (EPKF) are implemented in Matlab environment and their behavior are evaluated. The Enhanced Particle/ Kalman Filter (EPKF) provide the required initial location while there is no significant change in the computational cost compared with Extended Kalman Filter (EKF). Moreover in some data sets, the performance of the proposed filter approach is superior in terms of localization errors.
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Face Recognition using Extended Kalman Filter based Machine Learning

Face Recognition using Extended Kalman Filter based Machine Learning

Mrinal Kanti Bhowmik et. al. [16] performed a comparative study on fusion of visual and thermal images using different wavelet transformations like Haar and Daubechies (db2). They found wavelet a useful transformation for face recognition. Boqing Gong et. al. [17] proposed a method based on extracting facial features for 3-D faces. They emphasized on two components one for corresponding basic face structure and another corresponding expression change in the face based on the change in shape of 3D face. N. Sudha et al. [18] proposed an efficient self-configurable systolic architecture for very large scale integration implementation of a face recognition system. The proposed system applied principal component neural network (PCNN) with generalized Hebbian learning for extracting eigenfaces from the face database . Further Wonjun Hwang et al. [19] proposed a method which has two stages. First, in the preprocessing stage, a face image was transformed into an illumination-(insensitive image, called an “integral normalized gradient image,” by normalizing and integrating the smoothed gradients of a facial image. The hybrid Fourier features were extracted from different Fourier domains in different frequency bandwidths and then each feature was individually classified by linear discriminant analysis. Further Arindam Biswas et. al. [20] proposed a novel algorithm for extracting the region of interest of a face like eye pair, nostrils, and mouth area. Bart Karoon et. al. [21] addressed the influence of eye localization accuracy on face matching performance in
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A comparison of assimilation results from the ensemble Kalman Filter and a reduced-rank extended Kalman Filter

A comparison of assimilation results from the ensemble Kalman Filter and a reduced-rank extended Kalman Filter

The rms errors of the analysis from the optimal interpo- lation, the reduced-rank extended Kalman filter and the en- semble Kalman filter for the high viscosity case are shown in Fig. 13. All filtering techniques are able to significantly reduce the analysis error relative to the run without data as- similation. The forecast error from the unconstrained model run exhibits a striking quasi-periodic behavior with a period of approximately 9 years. The analysis error from the opti- mal interpolation exhibits similar behavior but with a smaller amplitude. The quasi-periodic behavior severely diminishes after the reduced-rank extended Kalman filtering is applied and it is nearly invisible in the rms errors of the analysis from the ensemble Kalman filter. The errors of the analysis from the optimal interpolation, the reduced-rank extended Kalman filter and the ensemble Kalman filter decrease dramatically during the first two years. After two years, the analysis error of the optimal interpolation is on average 30% of the fore- cast error when no data are assimilated; the analysis error of the reduced-rank extended Kalman filter is on average 10% of the forecast error without data assimilation; and the anal- ysis error of the ensemble Kalman filter is on average 6% of the forecast error without data assimilation. For the high vis-
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Estimation of the Wheel-Ground Contacttire Forces using Extended Kalman Filter

Estimation of the Wheel-Ground Contacttire Forces using Extended Kalman Filter

In this paper, the simulation model is a ten degree-of-freedom of a full-vehicle model that includes vertical suspension dynamics, roll, yaw and pitch motion. Using the vehicle speed, yaw rate, longitudinal and lateral accelerations of the vehicle at c.g. As the measurement vectors, the steering angle, and the braking as input control, the vehicle state histories and tire forces variables were estimated. The vehicle parameters for the Carsim and simulation are given in Table 1. Using equation (16), the observability matrixwas invertible at the current state and input as its Jacobian matrix has a full rank, hence the system was observable. Then, the estimated results were compared with the obtained responses from the Carsim. Figures 3 - 7 show the comparison of the results obtained from the Carsim and the estimated values using an EKF algorithm.
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A comparison of ensemble Kalman filter and extended 
		Kalman filter as the 
		estimation system in sensorless BLDC motor

A comparison of ensemble Kalman filter and extended Kalman filter as the estimation system in sensorless BLDC motor

In this paper, a new filtering algorithm is proposed for system control of the sensorless BLDC motor based on the Ensemble Kalman filter (EnKF). The proposed EnKF algorithm is used to estimate the speed and rotor position of the BLDC motor only using the measurements of terminal voltages and three-phase currents. The speed estimation performance of developed EnKF was compared with the Extended Kalman Filter (EKF) under the same conditions. Results indicate that the proposed EnKF as an observer shows better performance than that of the EKF.
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Flux and Speed Estimation of Induction Motors using Extended Kalman Filter

Flux and Speed Estimation of Induction Motors using Extended Kalman Filter

In above equations, 𝛥𝑡 represents the length of the sampling interval. Obviously, the smaller 𝛥𝑡 is better the Euler approximation is; otherwise this requires a fast microprocessor system for the on-line implementation of the filter. The employment of a stochastic approach overcomes in part these difficulties, because it intrinsically takes into account the model mismatching and therefore a not very small length 𝛥𝑡 can be chosen.

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Accurate Range-based Indoor Localization Using PSO-Kalman Filter Fusion

Accurate Range-based Indoor Localization Using PSO-Kalman Filter Fusion

Accurate indoor localization often depends on infrastructure support for distance estimation in range­based techniques. One can also trade off accuracy to reduce infrastructure investment by using relative positions of other nodes, as in range­free localization. Even for range­based meth­ ods where accurate Ultra­WideBand (UWB) signals are used, non line­of­sight (NLOS) conditions pose significant difficulty in accurate indoor localization. Existing solutions rely on additional measurements from sensors and typically correct the noise using a Kalman filter (KF). Solutions can also be customized to specific environments through extensive profiling. In this work, a range­ based indoor localization algorithm called PSO ­ Kalman Filter Fusion (PKFF) is proposed that minimizes the effects of NLOS on localization error without using additional sensors or profiling. Location estimates from a windowed Particle Swarm Optimization (PSO) and a dynamically ad­ justed KF are fused based on a weighted variance factor. PKFF achieved a 40 % lower 90­percentile root­mean­square localization error (RMSE) over the standard least squares trilateration algorithm at 61 cm compared to 102 cm.
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Study of Kalman, Extended Kalman and Unscented Kalman Filter (An Approach to Design a Power System)

Study of Kalman, Extended Kalman and Unscented Kalman Filter (An Approach to Design a Power System)

In the presence of non-linear functions the predicted states are approximated as the function of prior mean. The covariance are determined by linearizing the dynamic equations , and then the posterior covariance matrices are determined analytically for the linear system in EKF approach. In case of the EKF, a GRV is determined approximating the state distribution and then this GRV is propagated analytically through the ``first-order'' linearization of the nonlinear system. In this case the EKF can be credited with providing ``first-order'' approximations to the optimal terms such as optimal prediction, optimal gain. But these approximations, are not helpful always. Where the non- linearity value is more it can even introduce large errors in the true posterior mean as well as in the covariance of the transformed (Gaussian) random variable. This is not being an healthy approach to linearization might lead to sub-optimal performance and sometimes divergence (instability) of the filter. It is these ``flaws'' which will be amended in the next section using the UKF. [24]
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Design and Digital Implementation of Controller for PMSM Using Extended Kalman Filter

Design and Digital Implementation of Controller for PMSM Using Extended Kalman Filter

[9] F. Benchabane, A. Titaouine, O. Bennis, K. Yahia and D. Taibi, “Systematic Fuzzy Sliding Mode Approach with Extended Kalman Filter for Permanent-Magnet Synchr nous Motor,” Proceedin f the IEEE international co ference on Systems Ma d Cybernetics (SMC), 2010

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Employing Extended Kalman Filter in a Simple Macroeconomic Model

Employing Extended Kalman Filter in a Simple Macroeconomic Model

In this study, the estimation power of Extended Kalman Filter is tested within a simple Keynesian macroeconomic model. After the model is written in a non-linear state space form, Extended Kalman Filter emerges as the appropriate methodology to estimate both state variables and the parameters. The simulation results suggest that such a methodology can also be employed in explaining more complex macroeconomic dynamics.

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A discontinuous extended Kalman filter for non smooth dynamic problems

A discontinuous extended Kalman filter for non smooth dynamic problems

The following modified version of the EKF algorithm, termed the Discontinuous Extended Kalman Filter, DEKF , is now formulated for such systems: Let us assume that at a given time instan[r]

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