Learning-based Stance Phase Detection for Pedestrian Dead-reckoning System with Dynamic Gait Speeds

Self-Contained Pedestrian Tracking With Mems Sensors

10.32920/ryerson.14656776.v1 ◽

2021 ◽

Author(s):

Chengliang Huang

Keyword(s):

Particle Filtering ◽

Stance Phase ◽

Field Experiments ◽

Inertial Sensors ◽

Tracking System ◽

Dead Reckoning ◽

Pedestrian Tracking ◽

Indoor Wireless ◽

Wireless Positioning ◽

Pedestrian Dead Reckoning

Due to the limitations of current indoor wireless positioning technologies, a novel positioning/tracking solution has to be explored and developed, in order to locate a person anywhere anytime without any infrastructure. The purpose of this thesis is to present the result of the first phase of a long-period research to find such a solution and develop a practical system. In this thesis, using inertial sensors for positioning of people is selected to replace wireless solutions, considering the development of micro-electromechanical systems. A sensing module consisting of accelerometers, rate gyroscopes and magnetometers used to monitor human kinetics. In order to make this proposal practical, a synergy of existing strapdown inertial navigation and pedestrian dead-reckoning is proposed to improve the accuracy of positioning. Furthermore, the cyclic alternation of stance phase and swing phase in human walking is used to reduce errors accumulating during projection and integration of sensed accelerometer signals. Other than the improvement of some existing methods to detect stance phase and reset the velocity, several new methods are proposed to remove the integral drift during both phases of a human stride. The algorithm to calculate heading of on the sensing module is also deduced to limit the integral drift of rate gyroscopes. All the methods and algorithms are applied in field experiments with carefully chosen sensing module mounted on human footwear. The results show promising accuracy of tracking, hence validate the feasibility of self-contained pedestrian tracking system with inertial sensors. Further work, especially with map correlation and particle filtering, will be done in the coming phases of the project to make the system applicable both outdoor and indoor.

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Enhanced Heuristic Drift Elimination with Adaptive Zero-Velocity Detection and Heading Correction Algorithms for Pedestrian Navigation

Sensors ◽

10.3390/s20040951 ◽

2020 ◽

Vol 20 (4) ◽

pp. 951 ◽

Cited By ~ 1

Author(s):

Ruihui Zhu ◽

Yunjia Wang ◽

Baoguo Yu ◽

Xingli Gan ◽

Haonan Jia ◽

...

Keyword(s):

Inertial Sensors ◽

Angular Rate ◽

Dead Reckoning ◽

Detection Accuracy ◽

Phase Detection ◽

Pedestrian Navigation ◽

Zero Velocity ◽

Accumulated Error ◽

Pedestrian Dead Reckoning ◽

Dominant Direction

As pedestrian dead-reckoning (PDR), based on foot-mounted inertial sensors, suffers from accumulated error in velocity and heading, an improved heuristic drift elimination (iHDE) with a zero-velocity update (ZUPT) algorithm was proposed for simultaneously reducing the error in heading and velocity in complex paths, i.e., with pathways oriented at 45°, curved corridors, and wide areas. However, the iHDE algorithm does not consider the changes in pedestrian movement modes, and it can deteriorate when a pedestrian walks along a straight path without a pre-defined dominant direction. To solve these two problems, we propose enhanced heuristic drift elimination (eHDE) with an adaptive zero-velocity update (AZUPT) algorithm and novel heading correction algorithm. The relationships between the magnitude peaks of the y-axis angular rate and the detection thresholds were established only using the readings of the three-axis accelerometer and the three-axis gyroscopic, and a mechanism for constructing temporary dominant directions in real time was introduced. Real experiments were performed and the results showed that the proposed algorithm can improve the still-phase detection accuracy of a pedestrian at different movement motions and outperforms the iHDE algorithm in complex paths with many straight features.

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Error Analysis of PDR System Using Dual Foot-mounted IMU

E3S Web of Conferences ◽

10.1051/e3sconf/20199402007 ◽

2019 ◽

Vol 94 ◽

pp. 02007 ◽

Cited By ~ 1

Author(s):

Jae Hong Lee ◽

Hojin Ju ◽

Chan Gook Park

Keyword(s):

Inertial Navigation System ◽

Stance Phase ◽

Dead Reckoning ◽

Step Length ◽

Fusion Algorithm ◽

Circular Boundary ◽

Position Errors ◽

Integration Approach ◽

Previous Algorithm ◽

Pedestrian Dead Reckoning

In this paper, we analyze the position errors of the pedestrian dead reckoning (PDR) system using foot-mounted IMU attached to each foot, and implement PDR system using dual foot-mounted IMU to reduce the analyzed error. The PDR system using foot-mounted IMU is generally based on an inertial navigation system (INS). To reduce bias and white noise errors, INS is combined with zero velocity update (ZUPT), which assumes that the pedestrian shoe velocity is zero at the stance phase. Although ZUPT could compensate the velocity and position, the heading drift still occurs. When analyzing the characteristics of the position error, the error shows a symmetrical characteristic. In order to reduce this error, the previous researches compensate for both positions by applying feet position constraints. The algorithm consists of applying a conventional PDR system to each foot and fusion algorithm combining both. The PDR system using foot-mounted IMU, one on each foot, is based on integration approach separately. The positions of both feet should be in a circle with a radius as step length during walking. The designed filter is constrained so that the position of both feet are in a circular boundary. The heading error that is symmetrically drifted is corrected by the position constraint when the pedestrian moves straight. Experimental results show the performance and usability of each previous algorithm to compensate for symmetric heading errors.

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Self-Contained Pedestrian Tracking With Mems Sensors

10.32920/ryerson.14656776 ◽

2021 ◽

Author(s):

Chengliang Huang

Keyword(s):

Particle Filtering ◽

Stance Phase ◽

Field Experiments ◽

Inertial Sensors ◽

Tracking System ◽

Dead Reckoning ◽

Pedestrian Tracking ◽

Indoor Wireless ◽

Wireless Positioning ◽

Pedestrian Dead Reckoning

Due to the limitations of current indoor wireless positioning technologies, a novel positioning/tracking solution has to be explored and developed, in order to locate a person anywhere anytime without any infrastructure. The purpose of this thesis is to present the result of the first phase of a long-period research to find such a solution and develop a practical system. In this thesis, using inertial sensors for positioning of people is selected to replace wireless solutions, considering the development of micro-electromechanical systems. A sensing module consisting of accelerometers, rate gyroscopes and magnetometers used to monitor human kinetics. In order to make this proposal practical, a synergy of existing strapdown inertial navigation and pedestrian dead-reckoning is proposed to improve the accuracy of positioning. Furthermore, the cyclic alternation of stance phase and swing phase in human walking is used to reduce errors accumulating during projection and integration of sensed accelerometer signals. Other than the improvement of some existing methods to detect stance phase and reset the velocity, several new methods are proposed to remove the integral drift during both phases of a human stride. The algorithm to calculate heading of on the sensing module is also deduced to limit the integral drift of rate gyroscopes. All the methods and algorithms are applied in field experiments with carefully chosen sensing module mounted on human footwear. The results show promising accuracy of tracking, hence validate the feasibility of self-contained pedestrian tracking system with inertial sensors. Further work, especially with map correlation and particle filtering, will be done in the coming phases of the project to make the system applicable both outdoor and indoor.

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S-PDR: SBAUPT-Based Pedestrian Dead Reckoning Algorithm for Free-Moving Handheld Devices

Geomatics ◽

10.3390/geomatics1020010 ◽

2021 ◽

Vol 1 (2) ◽

pp. 148-176

Author(s):

Maan Khedr ◽

Naser El-Sheimy

Keyword(s):

Smart Cities ◽

Dead Reckoning ◽

Human Motion ◽

Indoor Navigation ◽

Location Based Services ◽

Navigation Systems ◽

Short Term ◽

Navigation Solution ◽

Correction Technique ◽

Pedestrian Dead Reckoning

Mobile location-based services (MLBS) are attracting attention for their potential public and personal use for a variety of applications such as location-based advertisement, smart shopping, smart cities, health applications, emergency response, and even gaming. Many of these applications rely on Inertial Navigation Systems (INS) due to the degraded GNSS services indoors. INS-based MLBS using smartphones is hindered by the quality of the MEMS sensors provided in smartphones which suffer from high noise and errors resulting in high drift in the navigation solution rapidly. Pedestrian dead reckoning (PDR) is an INS-based navigation technique that exploits human motion to reduce navigation solution errors, but the errors cannot be eliminated without aid from other techniques. The purpose of this study is to enhance and extend the short-term reliability of PDR systems for smartphones as a standalone system through an enhanced step detection algorithm, a periodic attitude correction technique, and a novel PCA-based motion direction estimation technique. Testing shows that the developed system (S-PDR) provides a reliable short-term navigation solution with a final positioning error that is up to 6 m after 3 min runtime. These results were compared to a PDR solution using an Xsens IMU which is known to be a high grade MEMS IMU and was found to be worse than S-PDR. The findings show that S-PDR can be used to aid GNSS in challenging environments and can be a viable option for short-term indoor navigation until aiding is provided by alternative means. Furthermore, the extended reliable solution of S-PDR can help reduce the operational complexity of aiding navigation systems such as RF-based indoor navigation and magnetic map matching as it reduces the frequency by which these aiding techniques are required and applied.

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