Ultrasonic sensor configuration for mobile robot navigation systems to assist visually impaired person

Ultrasonic sensor is one of the electronic components used in designing a mobile robot navigation system to assist visually impaired person. However, no guideline or algorithm has been established so far to ease the selection and determination of optimum number of ultrasonic sensors to be used and the layout for the sensors. The purpose of this study is to obtain an algorithm that can be used as a guideline for selecting appropriate ultrasonic component model. The algorithm is used for determining the optimum numbers and optimum layout for ultrasonic sensors of interest when used for a mobile robot navigation system for a 180° obstacle detection using theoretical calculations. All theoretical values obtained are compared with real-time data using an actual ultrasonic sensor placed on experimental platform. This set up is used with different numbers and placements using the selected ultrasonic sensor, HC–SR04 and is compared with the theoretical values for validation. Then, relevant equations are used to calculate the number of sensors and layout used for another ultrasonic sensor, MA40B8 to show the correctness of the equations used in this study. The MA40B8 ultrasonic sensor was originally used for a 360° obstacle detection system. It is proven that the equations used in this study are valid theoretically and experimentally. The algorithm can also be used to decide the optimum numbers and optimum layout for ultrasonic sensors for a 180° obstacle detection

The Application of Geographic Information Systems to Support Wayfinding for People with Visual Impairments or Blindness

People with visual impairments or legal blindness are relying on differing, comprehensive information utilized for their individual mobility. Increasing the personal mobility of people with disabilities and thereby achieving a self-determined life are major steps toward a more inclusive society. Research and applications on mobility issues of people with visual impairments or blindness mainly focus on technical applications or assistive orientation and navigation devices, and less work is covering the individual needs, e.g., regarding the information required for wayfinding. Moreover, active participation of people with disabilities in research and development is still limited. ways2see offers a new online application to support individual mobility in context of pre-trip planning for people with visual impairments or blindness based on a Geographic Information System (GIS). Obstacles, barriers, landmarks, orientation hints, and directions for wayfinding are generated by user profiles. The underlying network for GIS analysis is designed as pedestrian network. This individually coded network approach integrates sidewalks and different types of crossings and implements various orientation and navigation attributes. ways2see integrates three research realms: firstly, implementing a participative and transdisciplinary research design; secondly, integrating personalized information aligned with the individual user needs; and thirdly, presenting result of GIS analysis through an accessible designed user interface

Self-Contained Pedestrian Tracking During Normal Walking Using an Inertial/Magnetic Sensor Module

This paper proposes a novel self-contained pedestrian tracking method using a foot-mounted inertial and magnetic sensor module, which not only uses the traditional zero velocity updates, but also applies the stride information to further correct the acceleration double integration drifts and thus improves the tracking accuracy. In our method, a velocity control variable is designed in the process model, which is set to the average velocity derived from stride information in the swing (nonzero velocity) phases or zero in the stance (zero-velocity) phases. Stride-based position information is also derived as the pseudomeasurements to further improve the accuracy of the position estimates. An adaptive Kalman filter is then designed to fuse all the sensor information and pseudomeasurements. The proposed pedestrian tracking method has been extensively evaluated using experiments, including both short distance walking with different patterns and long distance walking performed indoors and outdoors, and have been shown to perform effectively for pedestrian tracking

Analysis of Navigation Assistants for Blind and Visually Impaired People: A Systematic Review

Over the last few decades, the development in the field of navigation and routing devices has become a hindering task for the researchers to develop smart and intelligent guiding mechanism at indoor and outdoor locations for blind and visually impaired people (BVIPs). The existing research need to be analysed from a historical perception including early research on the first electronic travel aids to the use of modern artificial vision models for the navigation of BVIPs. Diverse approaches such as: e-cane or guide dog, infrared-based cane, laser based walker and many others are proposed for the navigation of BVIPs. But most of these techniques have limitations such as: infrared and ultrasonic based assistance has short range capacities for object detection. While laser based assistance can harm other people if it directly hit them on their eyes or any other part of the body. These trade-offs are critical to bring this technology in practice.To systematically assess, analyze, and identify the primary studies in this specialized field and provide an overview of the trends and empirical evidence in the proposed field. This systematic research work is performed by defining a set of relevant keywords, formulating four research questions, defining selection criteria for the articles, and synthesizing the empirical evidence in this area. Our pool of studies include 191 most relevant articles to the proposed field reported between 2011 and 2020 (a portion of 2020 is included). This systematic mapping will help the researchers, engineers, and practitioners to make more authentic decisions for finding gaps in the available navigation assistants and suggest a new and enhanced smart assistant application accordingly to ensure safety and accurate guidance of the BVIPs. This research work have several implications in particular the impact of reducing fatalities and major injuries of BVIPs.Qatar University [IRCC-2020-009]

Use of an inertial/magnetic sensor module for pedestrian tracking during normal walking

The ability to track pedestrians without any infrastructure support is required by numerous applications in the healthcare, augmented reality, and entertainment industries. In this paper, we present a simple self-contained pedestrian tracking method using a foot-mounted inertial and magnetic sensor module. Traditional methods normally incorporate double integration of the measured acceleration, but such methods are susceptible to the acceleration noise and integration drift. To avoid this issue, alternative approaches which make use of walking dynamics to aggregate individual stride have been explored. The key for stride aggregating is to accurately and reliably detect stride boundary and estimate the associated heading direction for each stride, but it is still not well solved yet due to sensor noise and external disturbance. In this paper, we propose to make use of the inertial sensor and magnetometer measurements for stride detection and heading direction determination. In our method, a simple and reliable stride detection method, which is resilient to random bouncing motions and sensor noise, is designed based on gyroscope and accelerometer measurements. Heading direction is then determined from the foot's orientation which fuses all the three types of sensor information together. The proposed pedestrian tracking method has been evaluated using experiments, including both short distance walking with different patterns and long distance walking performed indoors and outdoors. The good experimental results have illustrated the effectiveness of the proposed pedestrian tracking method

3D oceanographic data compression using 3D-ODETLAP

This paper describes a 3D environmental data compression technique for oceanographic datasets. With proper point selection, our method approximates uncompressed marine data using an over-determined system of linear equations based on, but essentially different from, the Laplacian partial differential equation. Then this approximation is refined via an error metric. These two steps work alternatively until a predefined satisfying approximation is found. Using several different datasets and metrics, we demonstrate that our method has an excellent compression ratio. To further evaluate our method, we compare it with 3D-SPIHT. 3D-ODETLAP averages 20% better compression than 3D-SPIHT on our eight test datasets, from World Ocean Atlas 2005. Our method provides up to approximately six times better compression on datasets with relatively small variance. Meanwhile, with the same approximate mean error, we demonstrate a significantly smaller maximum error compared to 3D-SPIHT and provide a feature to keep the maximum error under a user-defined limit

Implementación de tecnologías RFID e IoT inalámbricas en el Modelado de información de construcción (BIM)

ABSTRACT: The integration and installation of innovative Radio Frequency Identification (RFID) technologies in combination with wireless Internet of Things (IoT) technologies in Building Information Modelling (BIM), assigned building elements, can create connectivity between the physical- and the virtual world. Beyond the identification of physical objects, further information can be connected, which can be made available to different user groups during the entire life cycle of the building structure. This provides a high level of transparency, in that by scanning the tagged building elements, complete associated information can be accessed and presented to users via applications, in visual and audio form. One use of an RFID and BIM-supported electronic guidance system, namely for the visually impaired, has already been investigated in my bachelor thesis at the University of Applied Sciences (Technische Hochschule Mittelhessen, THM). This Master’s Thesis focuses on the implementation of passive RFID technology into BIM models in combining them with open-source software applications. BIM represents the digital twin of building models in the digital world and can be linked to physical structures (buildings, roads, sewer systems and such others) and building materials (e.g. textiles, mineral and plastic floor coverings, concrete components) by integrating RFID tags. Connecting the parametric BIM models with the physical building elements by using RFID and wireless IoT technologies in a multi-platform application enables the BIM building models to be actively used throughout the life cycle of a building, not only by the facility management, but also by the public for various use cases. During the literature review, suitable software and hardware components were selected, and a prototype multi-platform application for a navigation and positioning system was developed as proof of concept for the Industry Foundation Classes (IFC) file. (See Demo Version at https://opennavibim.herokuapp.com/ ). The challenge was to read the RFID tags in different installation scenarios. Depending on the installation situations (under, over or in the material), various requirements were specified for RFID tags and readers (RFID, handhold personal digital assistant “PDA”). In this field, further hardware developments are necessary.RESUMEN: Mediante la integración e instalación de la innovadora tecnología de identificación por radiofrecuencia (RFID, Radio Frequency Identification) en el modelado digital de información de construcción (BIM, Building Information Modelling), con la interconexión inalámbrica del internet de las cosas (IoT, Internet of Things), es posible crear una conectividad entre el mundo físico y el virtual. Más allá de la mera identificación de objetos existentes, esta conectividad permite incorporar información adicional, que puede ponerse en disposición de los diferentes grupos de usuarios que intervienen durante el ciclo completo de vida de la estructura de la edificación. Se consigue un alto de nivel de transparencia en ese traspaso de información, accesible por medio del escaneado de los elementos etiquetados en la edificación, al tener una completa información asociada que es presentada a los usuarios vía aplicaciones en formato visual o de audio. Una investigación en la aplicación de tecnología RFID basada en BIM para un sistema de navegación electrónica, destinada a personas con discapacidad visual, ha sido desarrollada en mi trabajo fin de grado en la Universidad de Ciencias Aplicadas de Mittelhessen (THM). El presente Trabajo Fin de Master se centra en la implementación de tecnología RFID pasiva en modelos BIM combinados con aplicaciones de software libre. El modelo BIM representa el gemelo digital de los elementos de construcción en el mundo virtual, permitiendo establecer una relación del modelo con estructuras físicas (edificios, carreteras o sistemas de alcantarillado, entre otros) y materiales de construcción (por ejemplo, textiles, cubiertas de suelo minerales o plásticas, componentes de hormigón, …) por medio de la integración de etiquetas RFID. La conexión de los modelos paramétricos BIM con los elementos físicos del edificio, mediante el uso de tecnologías RFID e IoT inalámbricas en una aplicación multiplataforma, permite que los modelos de construcción BIM se utilicen activamente a lo largo del ciclo de vida de un edificio, no solo por la gestión de las instalaciones, sino también por el público para diversos casos de uso. Durante la revisión bibliográfica, se seleccionaron los componentes de software y hardware adecuados, y se desarrolló un prototipo de aplicación multiplataforma para un sistema de navegación y posicionamiento como prueba de viabilidad del concepto del modelo Industry Foundation Classes (IFC). (Véase la versión de demostración en https://opennavibim.herokuapp.com/ ). La lectura de las etiquetas RFID en diferentes en diferentes situaciones de instalación presenta un desafío, dependiendo de la instalación (debajo, encima o en el material) los requisitos impuestos a las etiquetas y lectores RFID son diferentes. Por lo tanto, es necesario seguir desarrollando el hardware en este ámbito.Máster en Ingeniería de Caminos, Canales y Puertos (Plan 2020

Integrating Haptic Feedback into Mobile Location Based Services

Haptics is a feedback technology that takes advantage of the human sense of touch by applying forces, vibrations, and/or motions to a haptic-enabled device such as a mobile phone. Historically, human-computer interaction has been visual - text and images on the screen. Haptic feedback can be an important additional method especially in Mobile Location Based Services such as knowledge discovery, pedestrian navigation and notification systems. A knowledge discovery system called the Haptic GeoWand is a low interaction system that allows users to query geo-tagged data around them by using a point-and-scan technique with their mobile device. Haptic Pedestrian is a navigation system for walkers. Four prototypes have been developed classified according to the user’s guidance requirements, the user type (based on spatial skills), and overall system complexity. Haptic Transit is a notification system that provides spatial information to the users of public transport. In all these systems, haptic feedback is used to convey information about location, orientation, density and distance by use of the vibration alarm with varying frequencies and patterns to help understand the physical environment. Trials elicited positive responses from the users who see benefit in being provided with a “heads up” approach to mobile navigation. Results from a memory recall test show that the users of haptic feedback for navigation had better memory recall of the region traversed than the users of landmark images. Haptics integrated into a multi-modal navigation system provides more usable, less distracting but more effective interaction than conventional systems. Enhancements to the current work could include integration of contextual information, detailed large-scale user trials and the exploration of using haptics within confined indoor spaces

Human Motion Analysis with Wearable Inertial Sensors

High-resolution, quantitative data obtained by a human motion capture system can be used to better understand the cause of many diseases for effective treatments. Talking about the daily care of the aging population, two issues are critical. One is to continuously track motions and position of aging people when they are at home, inside a building or in the unknown environment; the other is to monitor their health status in real time when they are in the free-living environment. Continuous monitoring of human movement in their natural living environment potentially provide more valuable feedback than these in laboratory settings. However, it has been extremely challenging to go beyond laboratory and obtain accurate measurements of human physical activity in free-living environments. Commercial motion capture systems produce excellent in-studio capture and reconstructions, but offer no comparable solution for acquisition in everyday environments. Therefore in this dissertation, a wearable human motion analysis system is developed for continuously tracking human motions, monitoring health status, positioning human location and recording the itinerary. In this dissertation, two systems are developed for seeking aforementioned two goals: tracking human body motions and positioning a human. Firstly, an inertial-based human body motion tracking system with our developed inertial measurement unit (IMU) is introduced. By arbitrarily attaching a wearable IMU to each segment, segment motions can be measured and translated into inertial data by IMUs. A human model can be reconstructed in real time based on the inertial data by applying high efficient twists and exponential maps techniques. Secondly, for validating the feasibility of developed tracking system in the practical application, model-based quantification approaches for resting tremor and lower extremity bradykinesia in Parkinson’s disease are proposed. By estimating all involved joint angles in PD symptoms based on reconstructed human model, angle characteristics with corresponding medical ratings are employed for training a HMM classifier for quantification. Besides, a pedestrian positioning system is developed for tracking user’s itinerary and positioning in the global frame. Corresponding tests have been carried out to assess the performance of each system