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Path planning plays a vital role in a mobile robot navigation system. It essentially generates the shortest traversable path between two given points. There are many path planning algorithms that have been proposed by researchers all over the world; however, there is very little work focussing on path planning for a service environment. The general assumption is that either the environment is fully known or unknown. Both cases would not be suitable for a service environment. A fully known environment will restrict further expansion in terms of the number of navigation points and an unknown environment would give an inefficient path. Unlike other environments, service environments have certain factors to be considered, like user-friendliness, repeatability, scalability, and portability, which are very essential for a service robot. In this paper, a simple, efficient, robust, and environment-independent path planning algorithm for an indoor mobile service robot is presented. Initially, the robot is trained to navigate to all the possible destinations sequentially with a minimal user interface, which will ensure that the robot knows partial paths in the environment. With the trained data, the path planning algorithm maps all the logical paths between all the destinations, which helps in autonomous navigation. The algorithm is implemented and tested using a 2D simulator Player/Stage. The proposed system is tested with two different service environment layouts and proved to have features like scalability, trainability, accuracy, and repeatability. The algorithm is compared with various classical path planning algorithms and the results show that the proposed path planning algorithm is on par with the other algorithms in terms of accuracy and efficient path generation. [ABSTRACT FROM AUTHOR]

Path planning plays a vital role in a mobile robot navigation system. It essentially generates the shortest traversable path between two given points. There are many path planning algorithms that have been proposed by researchers all over the world; however, there is very little work focussing on path planning for a service environment. The general assumption is that either the environment is fully known or unknown. Both cases would not be suitable for a service environment. A fully known environment will restrict further expansion in terms of the number of navigation points and an unknown environment would give an inefficient path. Unlike other environments, service environments have certain factors to be considered, like user-friendliness, repeatability, scalability, and portability, which are very essential for a service robot. In this paper, a simple, efficient, robust, and environment-independent path planning algorithm for an indoor mobile service robot is presented. Initially, the robot is trained to navigate to all the possible destinations sequentially with a minimal user interface, which will ensure that the robot knows partial paths in the environment. With the trained data, the path planning algorithm maps all the logical paths between all the destinations, which helps in autonomous navigation. The algorithm is implemented and tested using a 2D simulator Player/Stage. The proposed system is tested with two different service environment layouts and proved to have features like scalability, trainability, accuracy, and repeatability. The algorithm is compared with various classical path planning algorithms and the results show that the proposed path planning algorithm is on par with the other algorithms in terms of accuracy and efficient path generation. [ABSTRACT FROM AUTHOR]

In this paper, a low cost mobile robot with a modular design that permits the easy change of the number of wheels is considered for generation of 3D digital maps by using ROS tools and a 3D light detection and distance measurement (LiDAR) sensor. The modular robot is thought for travelling through several environments with saving the energy by changing the number and arrangement of the wheels according to the environment. The presented robot can construct a 3D map in particular structured environment and the running performance was investigated by an extensive characterization. Furthermore, in light of the experimental tests, a new simple algorithm based exclusively of the processing of the LiDAR data is proposed with the aim of characterizing the surrounding environment with fixed landmarks and mobile targets. Finally, the limits of this prototype and of the proposed algorithm have been analyzed, highlighting new improvements in the future perspective development for permitting an autonomous environment perception with a simple, modular and low-cost device. [ABSTRACT FROM AUTHOR]

This paper presents application of a neural network in the task of planning a mobile robot trajectory. First part contains a review of literature focused on the mobile robots' orientation and overview of artificial neural networks' application in area of robotics. In these sections devices and approaches for collecting data of mobile robots environment have been specified. In addition, the principle of operation and use of artificial neural networks in trajectory planning tasks was also presented. The second part focuses on the mobile robot that was designed in a 3D environment and printed with PLA material. The main onboard logical unit is Arduino Mega. Control system consist of 8-bits microcontrollers and 13 Mpix camera. Discussion in part three describes the system positioning capability using data from the accelerometer and magnetometer with overview of data filtration and the study of the artificial neural network implementation to recognize given trajectories. The last chapter contains a summary with conclusions. [ABSTRACT FROM AUTHOR]

This article proposes the construction of autonomous mobile robots and designing of obstacle avoidance algorithms for them. Nowadays, mobile robots are gaining more and more popularity on the customer as well as industrial market, for example as automatic vacuum cleaners or lawnmowers. Obstacle avoidance algorithms play an important role in performance of this types of robots. The proposed algorithms were designed for builds with rather not expensive electronic components, especially sensors with limited precision and dynamics. The project began with the selection of needed parts and building materials as well as designing of the PCB and assembling the whole construction. The project included also designing and developing the software responsible for, among others, implementation of obstacle avoidance algorithms. After the project's completion, a series of tests in a closed environment was conducted to verify the quality of vehicles' performance. Results of tests were positive. [ABSTRACT FROM AUTHOR]

This paper presents a new approach in the field of trajectory tracking for nonholonomic mobile robot in presence of disturbances. The proposed control design is constructed by a kinematic controller, based on PD sliding surface using fuzzy sliding mode for the angular and linear velocities disturbances, in order to tend asymptotically the robot posture error to zero. Thereafter a dynamic controller is presented using as a sliding surface design, a fast terminal function (FTF) whose parameters are generated by a genetic algorithm in order to converge the velocity errors to zero in finite time and guarantee the asymptotic stability of the system using a Lyapunov candidate. The elaborated simulation works in the case of different trajectories confirm the robustness of the proposed approach. [ABSTRACT FROM AUTHOR]

In the automated environments, mobile robots play an important role to perform different tasks such as objects transportation and material handling. In this paper, a new method for a glassy elevator handling system based on H20 mobile robots is presented to connect distributed life science laboratories in multiple floors. Various labware and tube racks have to be transported to different workstations. Locating of elevator door, entry button detection, internal buttons recognition, robot arm manipulation, current floor estimation, and elevator door status checking are the main operations to realize a successful elevator handling system. The H20 mobile robot has dual arms where each arm consists of 6 revolute joints and a gripper. The gripper has two degrees of freedom. Different sensors have been employed with the robot to handle these operations such as Intel RealSense F200 vision sensor for entry and internal buttons detection with position estimation. A pressure sensor is used for current floor estimation inside the elevator. Also, an ultrasonic proximity distance sensor is utilized for checking the elevator door status. Different strategies including HSL color representation, adaptive binary threshold, optical character recognition, and FIR smoothing filter have been employed for the elevator operations. For pressing operation, a hand camera base and a new elevator finger model are designed. The elevator finger is resolved in a way to fit the arm gripper which is used also to manipulate the labware containers. The Kinematic solution is utilized for controlling the arms' joints. A server/client socket architecture with TCP/IP command protocol is used for data exchange between Multi-Floor System and the H20 robot arms. Many experiments were conducted in life science laboratories to validate the developed systems. Experimental results prove an efficient performance with high success rate under different lightening condition. [ABSTRACT FROM AUTHOR]

To apply a spinning hemisphere as a mobile robot drive is an unconventional idea. Equipping a mobile robot with two such hemispheres brings to life a device with absolutely novel properties. In this paper we derive kinematics models of a mobile robot with two driving hemispheres, analyse shortly their properties, and adopt a control algorithm designed to follow a path. There are two kinematics models presented: the full model of the original system, and the model of the simplified system, equivalent to the original one. The second model is expressed in two different coordinate systems – the later allowing for the application of known control algorithms to drive the robot. The performance of the analysed algorithm is illustrated by computer simulations. [ABSTRACT FROM AUTHOR]

This paper considers the practical application of the RGB-D Simultaneous Localization and Mapping (SLAM) techniques for localization of mobile robots. We attempt to answer the question: how the quality of the estimated sensor trajectory depends on the approach to RGB-D data processing in the SLAM system when RGB-D frames acquired on a real mobile robot are used. Experiments are performed on data obtained from robots of different classes, and from different environment types to present the problems characteristic to RGB-D data. Conclusions as to the robustness of particular architectures and solutions applied in SLAM are drawn on the basis of experimental results. Publicly available data sets and well-established performance metrics are used to ensure that the results are verifiable, reproducible and relevant. [ABSTRACT FROM AUTHOR]

The paper presents a set of software tools dedicated to support mobile robot navigation. The tools are used to process an image from a depth sensor. They are implemented in ROS framework and they are compatible with standard ROS navigation packages. The software is released with an open source licence. First of the tools converts a 3D depth image to a 2D scan in polar coordinates. It provides projection of the obstacles, removes the ground plane from the image and compensates sensor tilt angle. The node is faster than the standard node within ROS and it has additional functions increasing range of possible applications. The second tool allows detection of negative obstacles i.e. located below the ground plane level. The third tool estimates height and orientation of the sensor with RANSAC algorithm applied to the depth image. The paper presents also the results of usage of the tools with mobile platforms equipped with Microsoft Kinect sensors. The platforms are elements of the ReMeDi project within which the software was developed. [ABSTRACT FROM AUTHOR]

This paper presents results of Micro Airborne Radio Relay implementation designed to extend range of mobile robots in search and rescue missions. Architecture of routing device with hardware based on ARM development board is presented, as well as overview of based on mbed-rtos software. Selected radio solution with radio modem and antennas is described. Paper presents results of proposed system field tests. [ABSTRACT FROM AUTHOR]

Mobile robotic systems are becoming viable technologies for automating manufacturing processes in fields that traditionally have seen little automation. Such fields include pipeline construction, green energy development, Infrastructure and shipbuilding. To operate in these environments, the mobile robotic platform must provide controlled motion of a manufacturing toolset over the surface of a structure which is generally non-planar. One such example is welding a seam along a non-flat ship hull where the surface may consist of sections resembling common geometric shapes such as cylinders or spheres and the tool must follow a path defined by the weld seam. This paper will present a kinematic control approach applicable to one mobile robot topology performing a task on a cylindrical surface. This method is readily generalized to other robot topologies or surface geometries. The method is based on a kinematic model that predicts the robot motion and configuration joint parameters while on a nonplanar surface with the desired motion prescribed in local tool space. The effort is motivated by a practical application of welding on steel hulls or other surfaces and the results will be compared with these empirical experiences. A discussion of how these results can be used to guide future design of mobile robot platforms for manufacturing is provided. [ABSTRACT FROM AUTHOR]

In this article we propose the application of service mobile robots for control of building safety parameters. Indoor mobile robots are becoming a reality and their availability and applications are expected to grow rapidly in the near future. Such robots are usually equipped with cameras and laser range finders, which could be used to detect hazardous situations in their operating environment, such as evacuation route obstructions, emergency sign occlusions or accumulation of dangerous materials. We demonstrate how these safety-related augmentations of a mobile robot system can be achieved with few additional resources and validate experimentally the concept using an indoor robot for emergency sign and evacuation route control. [ABSTRACT FROM AUTHOR]

In the present paper, design and performance of 12-legged walking robot is described. The complete technical specification was developed for the proposed solution. The analysis of stability of the robot movements was undertaken. Communication between robot and operator is based on remote control procedures performed by means of own software which is written in versions for smartphone or desktop computer. The software version for desktop computers has additional useful features i.e. monitoring of the area of robot work/activity via a wireless camera mounted on fore side of the robot. [ABSTRACT FROM AUTHOR]

This paper proposes the design concept that prevents its total weight from increasing. The object of the methodology is to modify a conventional robot chassis for structural simplicity by composing the chassis from an elastic material so that it can reduce vibration and shock to the body. This idea makes it unnecessary to attach additional elements, such as suspension units; in addition, it means that it is possible to easily deform the chassis by forming long holes, and to decrease the total weight of the robot, even when the chassis is thick enough for functionality. It contributes to preventing the weight of the power source from increasing. Structural models for analyzing flexure of the chassis using the finite element method (FEM) are pursued. Also, dynamic behaviors of the chassis are clarified based on the modal analysis. The minor difference in error between the experimental and analytical data verifies that the models are useful in a practical application. [ABSTRACT FROM AUTHOR]

The paper presents a sequential neural network (NN) identification scheme for the four-wheeled mobile robot subject to wheel slip. The sequential identification scheme, different from conventional methods of optimization of a cost function, attempts to ensure stability of the overall system while the neural network learns the nonlinearities of the mobile robot. An on-line weight learning algorithm is developed to adjust the weights so that the identified model can adapt to variations of the characteristics and operating points in the four-wheeled mobile robot. The proposed identification system that can guarantee stability is derived from the Lyapunov stability theory. Computer simulations have been conducted to illustrate the performance of the proposed solution by a series of experiments on the emulator of the wheeled mobile robot. [ABSTRACT FROM AUTHOR]

This work is concerned on sensitivity analysis of semiautonomy algorithm of a mobile robot to environmental sensors' failures. Construction of the robot, semiautonomy algorithm and used sensors have been described. The algorithm bases on a reactive hybrid approach that merges data from different types of sensors and calculates resulting velocities. This algorithm also takes into account environmental sensors' damage by modifying the behavior of robot in accordance to actual sensors' set state of health. Simulation research using Matlab/ Simulink package and experimental tests' results of semiautonomy algorithm were presented. The experimental tests were carried out in outdoor conditions. The research and tests are performed for normal environmental sensors' operation and for selected sensors' damage. On that basis, sensitivity of semiautonomy algorithm to selected environmental sensors damage was tested. [ABSTRACT FROM AUTHOR]

This paper deals with modeling and control strategies of the motion of wheeled mobile robots. The model of the vehicle has two driving wheels and the angular velocities of the two wheels are independently controlled. To illustrate how the kinematics model of the system can be used to design P controller and a PI controller is applied. The nonlinear and linearlised models are simulated in MATLAB® and simulink. The results are drawn here to evaluate the performance of the proposed controllers with concerned graphics. [ABSTRACT FROM AUTHOR]

This paper deals with the terrain classification problem for an autonomous mobile robot. The robot is designed to operate in an outdoor environment. The classifier integrates data from RGB camera and 2D laser scanner. The camera provides information about visual appearance of the objects in front of the robot. The laser scanner provides data about distance to the objects and their ability to reflect infrared beam. In this paper we present the method which create terrain segments and classifies them using joint application of Support Vector Machine (SVM) classifier and AdaBoost algorithm. The classifica- tion results of the experimental verification are provided in the paper. [ABSTRACT FROM AUTHOR]

Localization in an unknown environment is one of the major issues faced by autonomous vehicles. The solution to this problem is delivered by the Simultaneous Localization and Mapping techniques, commonly known as SLAM. SLAM is the category of algorithms allowing a robot to map the surroundings and to keep an estimate of its position. Nowadays several SLAM methods are widely used. Though, many issues arise when SLAM is applied in a complex and unstructured environment. This article details an implementation of SLAM using improved Extended Kalman Filter (EKF). The aim is to provide a simple but reliable SLAM technique. The work has been carried out on a robot Seekur Jr, the mapping has been realized with a laser scanner. The applied EKF model with its modifications is presented. The techniques used to observe the environment and to identify the landmarks are outlined. The robustness and consistency of introduced modifications were justified by experiments [ABSTRACT FROM AUTHOR]

This paper presents a new solution in the roughness description based on 2,5D map. Three parameters for rough surface description were proposed. The research was performed to verify which parameter provides the best combination of time calculation and accuracy of the terrain roughness reconstruction. Prepared map may be used for mobile robot path planning. [ABSTRACT FROM AUTHOR]

Maps are very usefulfor understanding unknown places before visiting them as maps represent spatial relationships between various objects in a region. Using robots for map construction is an important field these days as robots can reach places which may be inaccessible to human beings. This paper presents a method to use the data obtained from a single ultrasonic sensor mounted on a robot, to construct a map and localize the robot within that map. Map of the previously unknown environment is created with the help of a mobile robot, built using Lego Mindstorms NXT assembled in a modified TriBot configuration. The robot is equipped with an ultrasonic sensor and is controlled from a computer system running a MATLAB program, which communicates with the NXT over a USB or Bluetooth connection and performs complex calculations that are not possible for the NXT itself After the map construction, the robot finds its position in the map by using a particle filter. Implementation has been done in MATLAB pro gramming environment using RWTH - Mindstorms NXT Toolbox and has been successfully tested for map construction of a room and localization within that room with the use of a TriBot. [ABSTRACT FROM AUTHOR]

The work covers analysis of mobility of a four-wheeled robot based on its dynamics model. Several configurations of robot's drive system are considered: one driven axle, two independently driven axles and drive transmission from one axle to another by means of a toothed belt. The analysis of robot's mobility is limited to cases of its motion with constant velocity on the ground with various inclinations and mechanical characteristics. It is assumed that robot's wheels roll without sliding. In the conducted investigations of robot's mobility, limitations resulting from wheels' interaction with the ground are taken into account. Based on results of the investigations, advantages and drawbacks of each of drive system configurations of the robot are discussed. [ABSTRACT FROM AUTHOR]