Path planning and obstacle avoidance algorithms are requested for robots working in more and more complicated environments. Standard methods usually reduce these tasks to the search of a path composed from lines and c...
详细信息
ISBN:
(纸本)9789728865832
Path planning and obstacle avoidance algorithms are requested for robots working in more and more complicated environments. Standard methods usually reduce these tasks to the search of a path composed from lines and circles or the planning is executed only with respect to a local neighborhood of the robot. Sophisticated techniques allow to find more natural trajectories for mobile robots, but applications are often limited to the offline case. The novel hierarchical method presented in this paper is able to find a long path in a huge environment with several thousand obstacles in real time. The solution, consisting of multiple cubic splines, is optimized by Particle Swarm Optimization with respect to execution time and safeness. The generated spline paths result in smooth trajectories which can be followed effectively by nonholonomic robots. The developed algorithm was intensively tested in various simulations and statistical results were used to determine crucial parameters. Qualities of the method were verified by comparing the method with a simple PSO path planning approach.
This article describes the development of a methodology for the learning of visual and reactive behaviours using reinforcement learning. With the use of artificial vision the environment is perceived in 3D, and it is ...
详细信息
ISBN:
(纸本)9789728865832
This article describes the development of a methodology for the learning of visual and reactive behaviours using reinforcement learning. With the use of artificial vision the environment is perceived in 3D, and it is possible to avoid obstacles that are invisible to other sensors that are more common in mobile robotics. Reinforcement learning reduces the need for intervention in behaviour design, and simplifies its adjustment to the environment, the robot and the task. The designed methodology is intended to be general;thus, in order to change the desired behaviour, only the reinforcement and the filtering of the image need to be changed. For the definition of the reinforcement a laser sensor is used, and for the definition of the states a fixed 3x3 grid is used. The behaviours learned were wall following, object following, corridor following and platform following. Results are presented with a Pioneer 2 AT. A Gazebo 3D simulator was used for the Learning and testing phase, and a test of the wall following behaviour was carried out in a real environment.
A central requirement for the development of robotic systems, that are capable of autonomous operation in non-specific environments, is the ability to create maps of their operating locale. The creation of these maps ...
详细信息
ISBN:
(纸本)9789728865832
A central requirement for the development of robotic systems, that are capable of autonomous operation in non-specific environments, is the ability to create maps of their operating locale. The creation of these maps is a non trivial process as the robot has to interpret the findings of its sensors so as to make deductions regarding the state of its environment. Current approaches fall into two broad categories: on-line and offline. An on-line approach is characterised by its ability to construct a map as the robot traverses its operating environment, however this comes at the cost of representational clarity. An offline approach on the other hand requires all sensory data to be gathered before processing begins but is capable of creating more accurate maps. In this paper we present a new means of constructing occupancy grid maps which addresses this problem.
In this paper a biologically inspired approach for compensating the limited angle of vision in obstacle detection systems of mobile robots is presented. Most of the time it is not feasible to exhaustively monitor the ...
详细信息
ISBN:
(纸本)9789728865832
In this paper a biologically inspired approach for compensating the limited angle of vision in obstacle detection systems of mobile robots is presented. Most of the time it is not feasible to exhaustively monitor the environment of a mobile robot. In order to nonetheless achieve safe navigation obstacle detection mechanisms need to keep in mind certain aspects of the environment. In mammals this task is carried out by the creature's short-term memory. Inspired by this concept an absolute local map storing obstacles in terms of representatives has been introduced in the obstacle detection and avoidance system of the outdoor robot RAVON. That way the gap between the fields of vision of two laser range finders can be monitored which prevents the vehicle from colliding with obstacles seen some time ago.
The paper presents a simultaneous force and length variation mode in shape memory alloy (SMA) robotic application. The robotic ankle contains four SMA actuators and a spherical articulation. In order to assure a high ...
详细信息
ISBN:
(纸本)9789728865832
The paper presents a simultaneous force and length variation mode in shape memory alloy (SMA) robotic application. The robotic ankle contains four SMA actuators and a spherical articulation. In order to assure a high efficient robotic architecture, the mechanical and the control structure have to assure a real-time response to the work environment changes. The load variations or the difference between the moment of full contact step and the non contact moment for a waking robot are the standard situations for a SMA robotic ankle. The paper is divided in five sections. First section makes a short introduction in the physical description and conventional applications of shape memory alloy materials. Then, are presented the mathematical model for robotic ankle, the walking robot geometrical structure and the causality ordering of the active pair of legs, in this case with one free joint. In the last section some experimental results are presented. These results were obtained by using MATLAB programs, conceived by authors, for design and simulation of walking robots control algorithms.
In this work we present the initial implementation of a middleware software tool called the Hardware Abstraction Layer (HABLA). This tool isolates the control architecture of an autonomous computational system, like a...
详细信息
ISBN:
(纸本)9789728865832
In this work we present the initial implementation of a middleware software tool called the Hardware Abstraction Layer (HABLA). This tool isolates the control architecture of an autonomous computational system, like a robot, from its particular hardware implementation. It is provided with a set of general sensors and typical sensorial processing mechanisms of this kind of autonomous systems allowing for its application to different commercial platforms. This way, the HABLA permits the control designer to focus its work on higher-level tasks minimizing the time spent on the adaptation of the control architecture to different hardware configurations. Another important feature of the HABLA is that both hardware-HABLA and HABLA-control communications take place through standard TCP sockets, permitting the distribution of the computational cost over different computers. In addition, it has been developed in JAVA, so it is platform independent. After presenting the general HABLA diagram and operation structure, we consider a real application using the same deliberative control architecture on two different autonomous robots: an Aibo legged robot and a Pioneer 2Dx wheeled robot.
In today's complex enterprise environments, providing continuous service for applications is a key component of a successful robotized implementing of manufacturing. High availability (HA) is one of the components...
详细信息
ISBN:
(纸本)9789728865832
In today's complex enterprise environments, providing continuous service for applications is a key component of a successful robotized implementing of manufacturing. High availability (HA) is one of the components contributing to continuous service provision for applications, by masking or eliminating both planned and unplanned systems and application downtime. This is achieved through the elimination of hardware and software single points of failure (SPOF). A high availability solution will ensure that the failure of any component of the solution - either hardware, software or system management, will not cause the application and its data to become permanently unavailable. High availability solutions should eliminate single points of failure through appropriate design, planning, hardware selection, software configuring, application control, carefully environment control and change management discipline. In short, one can define high availability as the process of ensuring an application is available for use by duplicating and/or sharing hardware resources managed by a specialized software component. A high availability solution in robotized manufacturing provides automated failure detection, diagnosis, application recovery, and node (robot controller) re integration. The paper discusses the implementing of a high availability solution in a robotized manufacturing line.
Environmental research is an area where robotics platforms can be applied as solutions for different problems to help or automate certain tasks, with the purpose of being more efficient or also safer for the researche...
详细信息
Environmental research is an area where robotics platforms can be applied as solutions for different problems to help or automate certain tasks, with the purpose of being more efficient or also safer for the researchers involved. This paper presents the Kamanbare platform. Kamanbar6 is a bioinspired robotic platform, whose main goal is to climb trees for environmental research applications, applied in tasks such as gathering botanical specimen, insects, climatic and arboreal fauna studies, among others. Kamanbare is a platform that provides flexibility both in hardware and software, so that new applications may be developed and integrated without the need of extensive knowledge in robotics.
In this paper we illustrate the architecture and the main features of a bio-inspired control system employed to govern an anthropomorphic artificial Arm. The manipulation system we developed was designed starting from...
详细信息
ISBN:
(纸本)9789728865825
In this paper we illustrate the architecture and the main features of a bio-inspired control system employed to govern an anthropomorphic artificial Arm. The manipulation system we developed was designed starting from a deeply study of the human limb from the anatomical, physiological and neurological point of view. In accordance with the general view of the Biorobotics field we try to replicate the structure and the functionalities of the natural limb. Thanks to this biomimetic approach we obtained a system that can perform movements similar to those of the natural limb. The control system is organized in a hierarchical way. The low level controller emulates the neural circuits located in the human spinal cord and is charged to reproduce the reflexes behaviors and to control the arm stiffness. The high level control system generates the arm trajectory performing the inverse kinematics and furnishing the instantaneous muscles reference position. In particular we implemented the Inverse kinematic using a gradient based algorithm;at each step the actuators movements are arranged in order to decrease the distance between the wrist and the target position. Simulation and experimental results shows the ability of the control system in governing the arm to follow a predefined trajectory and to perform human like reflexes behaviors.
This paper presents an approach to the formal verification of safety properties of the behaviour-based control network of the mobile outdoor robot RAYON. In particular, we consider behaviours that are used for the com...
详细信息
This paper presents an approach to the formal verification of safety properties of the behaviour-based control network of the mobile outdoor robot RAYON. In particular, we consider behaviours that are used for the computation of the projected vehicle's velocity from obstacle proximity sensor data and inclination information. We describe how this group of behaviours is implemented in the synchronous language Quartz in order to be formally verified using model checking techniques of the Averest verification framework. Moreover, by integrating the automatically generated and verified code into the behaviour network, it can be guaranteed that the robot slows down and stops as required by the given safety specifications.
暂无评论