A Novel Crosstalk Elimination Method for Sonar Ranging System in Rescue Robot

AbstractUltrasonic crosstalk can cause false distance measurements and reduce the work efficiency of sonar ranging system. To enhance the performance of sonar ranging system in rescue robot, quadrature phase shift keying (QPSK) excitation sequences modulated using chaotic codes are proposed to fire sonar sensors. In order to obtain the best echo correlation characteristics, a genetic algorithm (GA) is used to optimize the initial values of the chaotic codes. Real experiments have been implemented using a sonar ranging system consisting of eight-channel SensComp 600 series electrostatic sensors excited with 2ms QPSK sequences. Experimental results show that the optimized QPSK excitation sequences can make eight channels sonar ranging system work together without crosstalk

A survey on acoustic positioning systems for location-based services

Positioning systems have become increasingly popular in the last decade for location-based services, such as navigation, and asset tracking and management. As opposed to outdoor positioning, where the global navigation satellite system became the standard technology, there is no consensus yet for indoor environments despite the availability of different technologies, such as radio frequency, magnetic field, visual light communications, or acoustics. Within these options, acoustics emerged as a promising alternative to obtain high-accuracy low-cost systems. Nevertheless, acoustic signals have to face very demanding propagation conditions, particularly in terms of multipath and Doppler effect. Therefore, even if many acoustic positioning systems have been proposed in the last decades, it remains an active and challenging topic. This article surveys the developed prototypes and commercial systems that have been presented since they first appeared around the 1980s to 2022. We classify these systems into different groups depending on the observable that they use to calculate the user position, such as the time-of-flight, the received signal strength, or the acoustic spectrum. Furthermore, we summarize the main properties of these systems in terms of accuracy, coverage area, and update rate, among others. Finally, we evaluate the limitations of these groups based on the link budget approach, which gives an overview of the system's coverage from parameters such as source and noise level, detection threshold, attenuation, and processing gain.Agencia Estatal de InvestigaciónResearch Council of Norwa

A Robust Platform for Mobile Robotics Teaching and Developing Using Arduino’s Integrated Development Environment (IDE) for Programming the Arduino MEGA 2560

In light of the rapid pace at which development happens with modern technology, mobile robots play an important role in our daily lives. This is due to their great importance in facilitating the affairs of life in various economic, commercial, industrial, scientific, and many other fields. In this research and project, we have restructured the microcontroller and system for one of the mobile robots (CEENBOT) that was designed by the University of Nebraska and replaced it with an Arduino Mega 2560. The purpose of using the Arduino Mega 2560 robot is to provide alternative programming for the CEENBOT platform to support an Arduino programming option. It is an open-source program which makes it easily accessible for developers and programmers. The Arduino Mega 2560 is an open-source electronics platform built on easy-to-use hardware and software. The Arduino Mega 2560 robot provides one of the most accessible ways to install different sensors and can be used in different aspects or applications that can be useful for mobile robotics teaching and development. Following the completion of this research and project, the electrical and computer engineering department at the University of Nebraska - Lincoln will be able to enhance its existing robotics course offerings using this robot. New laboratories have been created for teaching and development in this research. The laboratories include Simulink Getting Started, Simulink with Arduino Mega 2560, Integrated development environment IDE Getting Started with Arduino Mega 2560, Getting to Know the Robot Hardware, Getting Started on Moving the Robot, Obstacle Avoidance, Wireless Communication, and Create Your Own Lab Adventure. Advisors: Alisa Gilmore and Bing Che

Spatial Learning for Robot Locialization

Although evolutionary algorithms have been employed to automatically synthesize control and behavior programs for robots and even design the physical structures of the robots, it is impossible for evolution to anticipate the detailed structure of specific environments that the robot might have to deal with. Robots must thus possess mechanisms to learn and adapt to the environments they encounter. One such mechanism that is of importance to mobile robots is that of spatial learning, i.e., the ability to learn the spatial locations of objects and places in the environment, which would allow them to successfully explore and navigate in a-priori unknown environments. This paper proposes a computational model for the acquisition and use of spatial information that is inspired by the role of the hippocampal formation in animal spatial learning and navigation

Advances in Sonar Technology

The demand to explore the largest and also one of the richest parts of our planet, the advances in signal processing promoted by an exponential growth in computation power and a thorough study of sound propagation in the underwater realm, have lead to remarkable advances in sonar technology in the last years.The work on hand is a sum of knowledge of several authors who contributed in various aspects of sonar technology. This book intends to give a broad overview of the advances in sonar technology of the last years that resulted from the research effort of the authors in both sonar systems and their applications. It is intended for scientist and engineers from a variety of backgrounds and even those that never had contact with sonar technology before will find an easy introduction with the topics and principles exposed here

Collective cluster-based map merging in multi robot SLAM

New challenges arise with multi-robotics, while information integration is among the most important problems need to be solved in this field. For mobile robots, information integration usually refers to map merging . Map merging is the process of combining partial maps constructed by individual robots in order to build a global map of the environment. Different approaches have been made toward solving map merging problem. Our method is based on transformational approach, in which the idea is to find regions of overlap between local maps and fuse them together using a set of transformations and similarity heuristic algorithms. The contribution of this work is an improvement made in the search space of candidate transformations. This was achieved by enforcing pair-wise partial localization technique over the local maps prior to any attempt to transform them. The experimental results show a noticeable improvement (15-20%) made in the overall mapping time using our technique

The development of localisation capabilities and control for a low-cost robot

Includes bibliographical references (leaves 58-61).A fully autonomous robot which can perform dangerous or mundane tasks is the ideal outcome of robotic research. A variety of commercially available household robots such as robotic vacuum cleaners exist but are limited in their navigation ability. In general, they tend to use random search patterns to navigate a room and overestimate the time required to clean the room in order to ensure covering the entire area. The ability to map the environment and then use this map to navigate is an essential step towards total autonomy, and would greatly improve the efficiency of these household robots. Autonomous mapping is a complex problem as the robot must use sensor readings to generate a map while at the same time using that map to locate itself and navigate. One component of the mapping task is localisation. This is the process of determining position and orientation from sensor data given a known map. This was the focus of this work as a first-step towards an autonomous mapping robot. This project continued the work of an undergraduate thesis in which a robot vacuum base was built. Using this base, the sensing and control systems were developed. The selection of a suitable controller was an important aspect of the development. It had to be suitable not only for this task but allow for expansion of the control capabilities should the project be extended. The Gumstix/Roboaudiostix embedded system was chosen and performed successfully. Its extremely small size and low power requirements are a feature of the system