Odometry Correction of a Mobile Robot Using a Range-Finding Laser

Two methods for improving odometry using a pan-tilt range-finding laser is considered. The first method is a one-dimensional model that uses the laser with a sliding platform. The laser is used to determine how far the platform has moved along a rail. The second method is a two-dimensional model that mounts the laser to a mobile robot. In this model, the laser is used to improve the odometry of the robot. Our results show that the one-dimensional model proves our basic geometry is correct, while the two-dimensional model improves the odometry, but does not completely correct it

Design And Construction Of A Robotic Vehicle To Assist During Planetary Surface Operations

In the near future, astronauts will explore new planetary surfaces in the Solar System. To enable peak performance, these astronauts will need to utilize all of the tools at their disposal. It is proposed that one such tool is a planetary surface rover designed specifically to assist the astronauts during their Extra-Vehicular-Activities (EVA’s). This rover is designed and built to operate in concert with existing analog planetary surface infrastructure at the University of North Dakota (UND). This rover will be remotely controlled by an astronaut located on the planetary surface, enabling real-time operation and obstacle avoidance. The rover will act primarily as a relay for audio and video communications between the astronauts in the field and the Inflatable Lunar Habitat (ILH), or another planetary outpost. This rover will be designed to enable storage for tools and samples, freeing the astronauts from the tedious and physically demanding task of carrying items for long distances encumbered by an EVA suit. This thesis will describe the design of the rover and the rationale for each design decision. Upon completion of the rover, this thesis will report on the real-world performance of the rover, the effectiveness of the subsystems, and the lessons learned as a result of initial testing. Using the rover and the information obtained from this thesis, future astronaut-rover interaction studies will be conducted that will be important to the future of human planetary exploration

Design and analysis of Intelligent Navigational controller for Mobile Robot

Since last several years requirement graph for autonomous mobile robots according to its virtual application has always been an upward one. Smother and faster mobile robots navigation with multiple function are the necessity of the day. This research is based on navigation system as well as kinematics model analysis for autonomous mobile robot in known environments. To execute and attain introductory robotic behaviour inside environments(e.g. obstacle avoidance, wall or edge following and target seeking) robot uses method of perception, sensor integration and fusion. With the help of these sensors robot creates its collision free path and analyse an environmental map time to time. Mobile robot navigation in an unfamiliar environment can be successfully studied here using online sensor fusion and integration. Various AI algorithm are used to describe overall procedure of mobilerobot navigation and its path planning problem. To design suitable controller that create collision free path are achieved by the combined study of kinematics analysis of motion as well as an artificial intelligent technique. In fuzzy logic approach, a set of linguistic fuzzy rules are generated for navigation of mobile robot. An expert controller has been developed for the navigation in various condition of environment using these fuzzy rules. Further, type-2 fuzzy is employed to simplify and clarify the developed control algorithm more accurately due to fuzzy logic limitations. In addition, recurrent neural network (RNN) methodology has been analysed for robot navigation. Which helps the model at the time of learning stage. The robustness of controller has been checked on Webots simulation platform. Simulation results and performance of the controller using Webots platform show that, the mobile robot is capable for avoiding obstacles and reaching the termination point in efficient manner

Effort reduction and collision avoidance for powered wheelchairs : SCAD assistive mobility system

The new research described in this dissertation created systems and methods to assist wheelchair users and provide them with new realistic and interesting driving opportunities. The work also created and applied novel effort reduction and collision avoidance systems and some new electronic interactive devices. A Scanning Collision Avoidance Device (SCAD) was created that attached to standard powered wheelchairs to help prevent children from driving into things. Initially, mechanical bumpers were used but they made many wheelchairs unwieldy, so a novel system that rotated a single ultra-sonic transducer was created. The SCAD provided wheelchair guidance and assisted with steering. Optical side object detectors were included to cover blind spots and also assist with doorway navigation. A steering lockout mode was also included for training, which stopped the wheelchair from driving towards a detected object. Some drivers did not have sufficient manual dexterity to operate a reverse control. A reverse turn manoeuvring mode was added that applied a sequential reverse and turn function, enabling a driver to escape from a confined situation by operating a single turn control. A new generation of Proportional SCAD was created that operated with proportional control inputs rather than switches and new systems were created to reduce veer, including effort reduction systems. New variable switches were created that provided variable speed control in place of standard digital switches and all that research reduced the number of control actions required by a driver. Finally, some new systems were created to motivate individuals to try new activities. These included a track guided train and an adventure playground that including new interactive systems. The research was initially inspired by the needs of young people at Chailey Heritage, the novel systems provided new and more autonomous driving opportunities for many powered wheelchair users in less structured environments.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Climbing and Walking Robots

Nowadays robotics is one of the most dynamic fields of scientific researches. The shift of robotics researches from manufacturing to services applications is clear. During the last decades interest in studying climbing and walking robots has been increased. This increasing interest has been in many areas that most important ones of them are: mechanics, electronics, medical engineering, cybernetics, controls, and computers. Today’s climbing and walking robots are a combination of manipulative, perceptive, communicative, and cognitive abilities and they are capable of performing many tasks in industrial and non- industrial environments. Surveillance, planetary exploration, emergence rescue operations, reconnaissance, petrochemical applications, construction, entertainment, personal services, intervention in severe environments, transportation, medical and etc are some applications from a very diverse application fields of climbing and walking robots. By great progress in this area of robotics it is anticipated that next generation climbing and walking robots will enhance lives and will change the way the human works, thinks and makes decisions. This book presents the state of the art achievments, recent developments, applications and future challenges of climbing and walking robots. These are presented in 24 chapters by authors throughtot the world The book serves as a reference especially for the researchers who are interested in mobile robots. It also is useful for industrial engineers and graduate students in advanced study

Fully automated urban traffic system

The replacement of the driver with an automatic system which could perform the functions of guiding and routing a vehicle with a human's capability of responding to changing traffic demands was discussed. The problem was divided into four technological areas; guidance, routing, computing, and communications. It was determined that the latter three areas being developed independent of any need for fully automated urban traffic. A guidance system that would meet system requirements was not being developed but was technically feasible

A low-cost intelligent localisation system to improve cyclist safety

Cycling is an increasingly popular mode of travel in cities owing to the great advantages that it offers in terms of space consumption, health and environmental sustainability, and it is therefore favoured and promoted by many city authorities worldwide. A large number of recently introduced cycling-related schemes in many cities demonstrates this trend. However, the relatively low safety of pedal cycles as perceived by the users currently presents itself as a hurdle, and therefore cycling has yet to be adopted to a wider extent by users as a true alternative to the private car. Rising accident numbers, unfortunately, confirm this perception as reality, with a particular source of hazard appearing to originate from the interaction of cyclists with motorised traffic at low speeds in urban areas. Technological advances in recent years have resulted in a number of attempts to develop systems to prevent cyclist-vehicle collisions, but they have generally stumbled upon the challenge of accurate cyclist localisation and tracking, which can enable predicting a collision within a short-term time-horizon (5-10 seconds). Indeed, cyclist positioning accuracy is essential for any collision avoidance system, not only to ensure the effective operation of the system but also to minimise the occurrence of false alerts. Thus, motivated by the poor safety record, the research reported here involves the development and testing of an innovative technological solution for accurately localising and tracking cyclists, where the ultimate aim is to utilise the techniques in a concept called Cyclist 360° Alert to avoid collisions. The overarching innovation of this PhD is the development of the instrumented bicycle system, called iBike, which can be employed to track cyclists’ positions more precisely. The system relies on bicycles being instrumented with low-cost Micro-electromechanical systems (MEMS) sensors, and utilises multiple Kalman filters, which were developed from the geometrical and kinematics modelling of the bicycles, to conduct a multi-sensor fusion on the iBike acquisition data with the measurements from the Global Positioning System, Wi-Fi hotspots and mobile communication systems. Apart from the above, the thesis also reports on the results obtained from a number of field trials where an enhanced off-the-shelf positioning system was employed to validate the developed system. The overall results from the field experiments demonstrate that, on average with an 80% probability, the iBike system can be used to estimate a position with less than 0.5 m error compared to a 16.2 m error from the enhanced positioning system under the same circumstances. Thus, the results from the field trials using the iBike have shown successful outcomes for the developed methodologies. This means that the iBike can be used to predict a collision more precisely. These results are presented in detail together with the hardware and software of the iBike system in this thesis

Nonlinear control of wheeled mobile robots

The purpose of this project is to implement an autonomous navigation system using nonlinear control techniques to control a wheeled mobile robot (WMR) to follow a preplanned trajectory and track a path. Two other aspects of navigation are studied: path planning and obstacle avoidance. Those three aspects are integrated into a navigation strategy that manages navigation and prevents deadlocks. Two nonlinear control techniques for path tracking and trajectory following have been developed and implemented. In the first approach, a fuzzy logic controller is used to drive the robot through a set of waypoints leading to the destination. In another approach, a controller derived from a Lyapunov function is used to track a reference trajectory that is time dependent. For path planning, a novel optimization technique based on dynamic programming has been developed. The curvature velocity method has been used for obstacle avoidance. The testing was conducted on a P3-AT all-terrain mobile robot equipped with encoders, a gyroscope, and sonar sensors for localization and environment perception. The test results validate the effectiveness of the different approaches that have been developed

Techniques mixtes de positionnement et la navigation véhiculaire

Les véhicules intelligents sont des véhicules dotés de systèmes permettant d’alerter le conducteur ou de prendre une décision en cas de danger imminent. Une condition sine qua non pour garantir un bon fonctionnement de ces systèmes est d’avoir une localisation précise du véhicule. En tirant profit des capteurs embarqués dans un véhicule, on peut exploiter la redondance de l’information afin d’obtenir un positionnement fiable. Cette information de localisation peut être alors utilisée dans un système d’aide à la conduite. Cette étude va se focaliser sur deux aspects. Dans un premier temps, un effort sera porté sur l'aspect localisation précise du véhicule lors de son déplacement. Il s’agit d’utiliser des approches bayésiennes pour fusionner les informations provenant de systèmes hétérogènes de navigation telle que le GPS et une centrale inertielle (INS) auxquels sera rajoutée ensuite l'odométrie. L'accent sera mis sur la précision des résultats. Ensuite, nous allons nous mettre en œuvre un régulateur de vitesse intelligent pour couvrir l’aspect navigation d’un véhicule