Online Calibration of Traffic Prediction Models

2005 ◽  
Vol 1934 (1) ◽  
pp. 235-245 ◽  
Author(s):  
Constantinos Antoniou ◽  
Moshe Ben-Akiva ◽  
Haris N. Koutsopoulos
Keyword(s):  
Kalman Filter ◽  
Prediction Models ◽  
Unscented Kalman Filter ◽  
State Space Model ◽  
The United States ◽  
Sensor Data ◽  
Solution Technique ◽  
Online Calibration ◽  
Estimation And Prediction ◽  
Innovative Solution

A methodology for the online calibration of the speed–density relationship is formulated as a flexible state–space model. Applicable solution approaches are discussed and three of them–-the extended Kalman filter (EKF), the iterated EKF, and the unscented Kalman filter (UKF)–-are selected and presented in detail. An application of the methodology with freeway sensor data from two networks in Europe and the United States is presented. The improvement in the estimation and prediction of speeds due to online calibration (compared with the speeds obtained from the relationship calibrated offline) is demonstrated. EKF provided the most straightforward solution to this problem and, indeed, achieved considerable improvements in estimation and prediction accuracy. The benefits obtained from the use of the more computationally expensive iterated EKF algorithm are shown. An innovative solution technique (UKF) is also presented.

Fast and Precise Glass Handling Using Visual Servo With Unscented Kalman Filter Dual Estimation

2017 ◽  
Vol 140 (4) ◽  
Author(s):  
Xiaowen Yu ◽  
Thomas Baker ◽  
Yu Zhao ◽  
Masayoshi Tomizuka
Keyword(s):  
Kalman Filter ◽  
Manufacturing Industry ◽  
Unscented Kalman Filter ◽  
Industrial Robot ◽  
Frame Rate ◽  
Sensor Data ◽  
Visual Servo ◽  
Dual Estimation ◽  
Low Frame Rate ◽  
Glass Piece

In the protective glass manufacturing industry for cell phones, placing glass pieces into the slots of the grinder requires submillimeter accuracy which only can be achieved by human workers, leading to a bottle neck in the production line. To address such issue, industrial robot equipped with vision sensors is proposed to support human workers. The high placing performance is achieved by a two step approach. In the first step, an eye-to-hand camera is installed to detect the glass piece and slot with robust vision, which can put the glass piece close to the slot and ensures a primary precision. In the second step, a closed-loop controller based on visual servo is adopted to guide the glass piece into the slot with dual eye-in-hand cameras. However, vision sensor suffers from a very low frame rate and slow image processing speed resulting in a very slow placing performance. In addition, the placing performance is substantially limited by the system parameter uncertainty. To compensate for these limitations, a dual-rate unscented Kalman filter (UKF) with dual-estimation is adopted for sensor data filtering and online parameter identification without requiring any linear parameterization of the model. Experimental results are presented to confirm the effectiveness of the proposed approach.

scholarly journals Enhanced PDR-BLE Compensation Mechanism Based on HMM and AWCLA for Improving Indoor Localization

Sensors ◽  
2021 ◽  
Vol 21 (21) ◽  
pp. 6972
Author(s):  
Harun Jamil ◽  
Faiza Qayyum ◽  
Faisal Jamil ◽  
Do-Hyeun Kim
Keyword(s):  
Kalman Filter ◽  
Indoor Environment ◽  
Indoor Localization ◽  
Unscented Kalman Filter ◽  
Sensor Data ◽  
Compensation Mechanism ◽  
Localization Algorithm ◽  
High Position ◽  
Zero Velocity ◽  
Conflicting Information

This paper presents an enhanced PDR-BLE compensation mechanism for improving indoor localization, which is considerably resilient against variant uncertainties. The proposed method of ePDR-BLE compensation mechanism (EPBCM) takes advantage of the non-requirement of linearization of the system around its current state in an unscented Kalman filter (UKF) and Kalman filter (KF) in smoothing of received signal strength indicator (RSSI) values. In this paper, a fusion of conflicting information and the activity detection approach of an object in an indoor environment contemplates varying magnitude of accelerometer values based on the hidden Markov model (HMM). On the estimated orientation, the proposed approach remunerates the inadvertent body acceleration and magnetic distortion sensor data. Moreover, EPBCM can precisely calculate the velocity and position by reducing the position drift, which gives rise to a fault in zero-velocity and heading error. The developed EPBCM localization algorithm using Bluetooth low energy beacons (BLE) was applied and analyzed in an indoor environment. The experiments conducted in an indoor scenario shows the results of various activities performed by the object and achieves better orientation estimation, zero velocity measurements, and high position accuracy than other methods in the literature.

Multi sensor data fusion based approach for the calibration of airdata systems

2011 ◽  
Vol 115 (1164) ◽  
pp. 113-122 ◽  
Author(s):  
M. Majeed ◽  
I. N. Kar
Keyword(s):  
Kalman Filter ◽  
Data Fusion ◽  
Test Data ◽  
Flight Control ◽  
Unscented Kalman Filter ◽  
Flight Test ◽  
Sensor Data ◽  
Sensor Data Fusion ◽  
Multi Sensor Data Fusion ◽  
Fusion Methods

AbstractAccurate and reliable airdata systems are critical for aircraft flight control system. In this paper, both extended Kalman filter (EKF) and unscented Kalman filter (UKF) based various multi sensor data fusion methods are applied to dynamic manoeuvres with rapid variations in the aircraft motion to calibrate the angle-of-attack (AOA) and angle-of-sideslip (AOSS) and are compared. The main goal of the investigations reported is to obtain online accurate flow angles from the measured vane deflection and differential pressures from probes sensitive to flow angles even in the adverse effect of wind or turbulence. The proposed algorithms are applied to both simulated as well as flight test data. Investigations are initially made using simulated flight data that include external winds and turbulence effects. When performance of the sensor fusion methods based on both EKF and UKF are compared, UKF is found to be better. The same procedures are then applied to flight test data of a high performance fighter aircraft. The results are verified with results obtained using proven an offline method, namely, output error method (OEM) for flight-path reconstruction (FPR) using ESTIMA software package. The consistently good results obtained using sensor data fusion approaches proposed in this paper establish that these approaches are of great value for online implementations.

Estimation of Forcing Function, Mistuning and Modal Damping in a Bladed Rotor

2019 ◽  
Author(s):  
Arjun Singh Chauhan ◽  
Alok Sinha
Keyword(s):  
Kalman Filter ◽  
State Space ◽  
Unscented Kalman Filter ◽  
State Space Model ◽  
Space Model ◽  
Vibration Data ◽  
Forcing Function ◽  
Modal Damping ◽  
Bladed Rotor ◽  
Augmented State

Abstract This paper deals with the estimation of forcing function, modal damping and mistuned modal stiffnesses in a bladed rotor. Previous research on parameter estimation in a mistuned bladed rotor relies on the knowledge of the forcing function as well as the vibration data. This paper presents two novel approaches. The first approach relies on knowledge of both the forcing and vibration data. The parameters are treated as states of the system and an augmented state space model is created. Unscented Kalman Filter is then used on the steady state data to estimate the parameters. The second approach eliminates the dependence on forcing data. Both the forcing and parameters are now treated as states of the system to construct an augmented state space model. Unscented Kalman Filter is then used on transient vibration data for estimation. Numerical results are presented for a simple model of a mistuned bladed rotor which considers a single mode of vibration per blade.

scholarly journals Attitude estimation for collision recovery of a quadcopter unmanned aerial vehicle

2019 ◽  
Vol 38 (10-11) ◽  
pp. 1286-1306 ◽  
Author(s):  
Adrian Battiston ◽  
Inna Sharf ◽  
Meyer Nahon
Keyword(s):  
Kalman Filter ◽  
Unmanned Aerial Vehicle ◽  
Unscented Kalman Filter ◽  
Real Data ◽  
Attitude Estimation ◽  
Sensor Data ◽  
Measurement Unit ◽  
Post Processing ◽  
Extensive Evaluation ◽  
Aerial Vehicle

An extensive evaluation of attitude estimation algorithms in simulation and experiments is performed to determine their suitability for a collision recovery pipeline of a quadcopter unmanned aerial vehicle. A multiplicative extended Kalman filter (MEKF), unscented Kalman filter (UKF), complementary filter, [Formula: see text] filter, and novel adaptive varieties of the selected filters are compared. The experimental quadcopter uses a PixHawk flight controller, and the algorithms are implemented using data from only the PixHawk inertial measurement unit (IMU). Performance of the aforementioned filters is first evaluated in a simulation environment using modified sensor models to capture the effects of collision on inertial measurements. Simulation results help define the efficacy and use cases of the conventional and novel algorithms in a quadcopter collision scenario. An analogous evaluation is then conducted by post-processing logged sensor data from collision flight tests, to gain new insights into algorithms’ performance in the transition from simulated to real data. The post-processing evaluation compares each algorithm’s attitude estimate, including the stock attitude estimator of the PixHawk controller, to data collected by an offboard infrared motion capture system. Based on this evaluation, two promising algorithms, the MEKF and an adaptive [Formula: see text] filter, are selected for implementation on the physical quadcopter in the control loop of the collision recovery pipeline. Experimental results show an improvement in the metric used to evaluate experimental performance, the time taken to recover from the collision, when compared with the stock attitude estimator on the PixHawk (PX4) software.

scholarly journals Application of Spherical-Radial Cubature Bayesian Filtering and Smoothing in Bearings Only Passive Target Tracking

Entropy ◽  
2019 ◽  
Vol 21 (11) ◽  
pp. 1088 ◽  
Author(s):  
Wasiq Ali ◽  
Yaan Li ◽  
Zhe Chen ◽  
Muhammad Asif Zahoor Raja ◽  
Nauman Ahmed ◽  
...  
Keyword(s):  
Kalman Filter ◽  
Target Tracking ◽  
Nonlinear Filtering ◽  
Unscented Kalman Filter ◽  
State Space Model ◽  
Moving Target ◽  
Bayesian Filtering ◽  
Tracking Problem ◽  
Cubature Kalman Filter ◽  
Passive Target Tracking

In this paper, an application of spherical radial cubature Bayesian filtering and smoothing algorithms is presented to solve a typical underwater bearings only passive target tracking problem effectively. Generally, passive target tracking problems in the ocean environment are represented with the state-space model having linear system dynamics merged with nonlinear passive measurements, and the system is analyzed with nonlinear filtering algorithms. In the present scheme, an application of spherical radial cubature Bayesian filtering and smoothing is efficiently investigated for accurate state estimation of a far-field moving target in complex ocean environments. The nonlinear model of a Kalman filter based on a Spherical Radial Cubature Kalman Filter (SRCKF) and discrete-time Kalman smoother known as a Spherical Radial Cubature Rauch–Tung–Striebel (SRCRTS) smoother are applied for tracking the semi-curved and curved trajectory of a moving object. The worth of spherical radial cubature Bayesian filtering and smoothing algorithms is validated by comparing with a conventional Unscented Kalman Filter (UKF) and an Unscented Rauch–Tung–Striebel (URTS) smoother. Performance analysis of these techniques is performed for white Gaussian measured noise variations, which is a significant factor in passive target tracking, while the Bearings Only Tracking (BOT) technology is used for modeling of a passive target tracking framework. Simulations based experiments are executed for obtaining least Root Mean Square Error (RMSE) among a true and estimated position of a moving target at every time instant in Cartesian coordinates. Numerical results endorsed the validation of SRCKF and SRCRTS smoothers with better convergence and accuracy rates than that of UKF and URTS for each scenario of passive target tracking problem.

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