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Path Planning (path + planning)
Selected AbstractsA New Immune Genetic Algorithm and Its Application in Redundant Manipulator Path PlanningJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 3 2004Xiaoping Luo In this paper, first the immune system is analyzed in a relatively deeper and all-sided point of view reflecting the fresh research in biology. Second, based on the previous statements, a new optimization method, the immune genetic algorithm (IGA), is presented by simulating the behavior of the biological immune system and is proved to converge to the global optimum with probability 1. Third, a new method on the multi-object optimization that is transformed into a single-object one is proposed based on the joints' best compliance in the redundant robot path planning using IGA. Last, the experiment results show that the method of this article behaves more successfully. © 2004 Wiley Periodicals, Inc. [source] Real-Time Trajectory Planning of the Industrial Robot IRB6400PROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2003Matthias Knauer Path planning of industrial robots requires the calculation of trajectories with respect to different optimization criteria, e.g. time optimal, energy optimal or wear and tear optimal solutions. These optimal control problems can be solved numerically, e.g., by direct solvers. In practice, inaccuracies or perturbations in the underlying model can cause the robot to fail in following the calculated path. When deviations of the precalculated trajectory or system parameters are detected an update of the robot trajectory is required in real-time. Therefore, a method based on the parametric sensitivity analysis of the optimal control problem is proposed to calculate admissible approximations for the solution of the perturbed robot trajectory problem in real-time. A model of ABB's common robot IRB 6400 is used to reveal the capabilities of the proposed method. [source] Real-time deadlock-free navigation for multiple mobile robotsELECTRICAL ENGINEERING IN JAPAN, Issue 3 2008Harunori Gakuhari Abstract This paper proposes a practicable navigation method for multiple mobile robots in a realistic environment. In the past, many navigation methods have been developed. However, they were often limited to a single robot and sometimes assumed robots with special mobility such as holonomic ones. From the viewpoint of practical applications it is indispensable that the number of robots is arbitrary and a general shape and mobility for them is allowed. In this study, deadlock-free navigation for nonholonomic mobile robots in a practical environment is given. In the proposed scheme, states of the environment and robots are fed back in real time, and global path planning is cyclically executed. This enables an adaptation to a changing environment and reliable, deadlock-free navigation for multiple robots. The real-time online path planning is performed by an efficient A* search in Configuration Spaces representing the robots and environment. The proposed method is tested in several simulations which represent typical complicated navigation situations. As a result, the effectiveness of the method is verified. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(3): 27, 36, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20714 [source] Tree search algorithm for assigning cooperating UAVs to multiple tasksINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 2 2008Steven J. Rasmussen Abstract This paper describes a tree search algorithm for assigning cooperating homogeneous uninhabited aerial vehicles to multiple tasks. The combinatorial optimization problem is posed in the form of a decision tree, the structure of which enforces the required group coordination and precedence for cooperatively performing the multiple tasks. For path planning, a Dubin's car model is used so that the vehicles' constraint, of minimum turning radius, is taken into account. Due to the prohibitive computational complexity of the problem, exhaustive enumeration of all the assignments encoded in the tree is not feasible. The proposed optimization algorithm is initialized by a best-first search and candidate optimal solutions serve as a monotonically decreasing upper bound for the assignment cost. Euclidean distances are used for estimating the path length encoded in branches of the tree that have not yet been evaluated by the computationally intensive Dubin's optimization subroutine. This provides a lower bound for the cost of unevaluated assignments. We apply these upper and lower bounding procedures iteratively on active subsets within the feasible set, enabling efficient pruning of the solution tree. Using Monte Carlo simulations, the performance of the search algorithm is analyzed for two different cost functions and different limits on the vehicles' minimum turn radius. It is shown that the selection of the cost function and the limit have a considerable effect on the level of cooperation between the vehicles. The proposed deterministic search method can be applied on line to different sized problems. For small-sized problems, it provides the optimal solution. For large-sized problems, it provides an immediate feasible solution that improves over the algorithm's run time. When the proposed method is applied off line, it can be used to obtain the optimal solution, which can be used to evaluate the performance of other sub-optimal search methods. Copyright © 2007 John Wiley & Sons, Ltd. [source] On-line estimation and path planning for multiple vehicles in an uncertain environmentINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 8 2004Jarurat Ousingsawat Abstract A unified approach to cooperative target tracking and path planning for multiple vehicles is presented. All vehicles, friendly and adversarial, are assumed to be aircraft. Unlike the typical target tracking problem that uses the linear state and nonlinear output dynamics, a set of aircraft nonlinear dynamics is used in this work. Target state information is estimated in order to integrate into a path planning framework. The objective is to fly from a start point to a goal in a highly dynamic, uncertain environment with multiple friendly and adversarial vehicles, without collision. The estimation architecture proposed is consistent with most path planning methods. Here, the path planning approach is based on evolutionary computation technique which is then combined with a nonlinear extended set membership filter in order to demonstrate a unified approach. A cooperative estimation approach among friendly vehicles is shown to improve speed and routing of the path. Copyright © 2004 John Wiley & Sons, Ltd. [source] Design and power management of a solar-powered "Cool Robot" for polar instrument networksJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 7 2007Laura E. Ray The Cool Robot is a four-wheel-drive, solar-powered, autonomous robot designed to support summertime science campaigns in Antarctica and Greenland over distances exceeding 500 km. This paper provides an overview of key features of the robot, including design for good mobility, high efficiency, and long-term deployment under solar power in harsh polar environments. The Cool Robot's solar panel box, comprising panels on four sides and a top panel, encounters insolation variations with a bandwidth of up to 1 Hz due to sastrugi. The paper details a unique photovoltaic control algorithm to accommodate these variations. We deployed the robot at Summit Camp, Greenland to validate its mobility and power budget and to assess the photovoltaic control system. The 61 kg robot drove continuously at 0.78 m/s on soft snow, its 160 W average power demand met by solar power alone under clear skies above 16° sun elevation. The power-control system reliably matched input with demand as insolation varied during testing. A simple GPS waypoint-following algorithm provides low-bandwidth path planning and course correction and demonstrated reliable autonomous navigation during testing over periods of 5,8 h. Field data validate the Cool Robot design models and indicate that it will exceed its design goal of carrying a 15 kg payload 500 km across Antarctica in 2 weeks. A brief description of instrument payloads and scientific studies aided by networks of such autonomous solar robots is provided. © 2007 Wiley Periodicals, Inc. [source] High-resolution millimeter-wave radar systems for visualization of unstructured outdoor environmentsJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 10 2006Graham Brooker This paper examines the use of millimeter-wave radar systems for visualization and navigation in unstructured outdoor environments. Three types of radar systems are described. The first is a long range, 94 GHz, frequency modulated interrupted continuous wave radar which is capable of producing two-dimensional (2D) reflectivity images to a range of more than 3 km. This is intended for use in long-range path planning. The second is a class of medium range 77 GHz frequency modulated continuous wave (FMCW) radar with two axis mirror scanners which is capable of producing high resolution threedimensional (3D) imagery out to 500 m at a reasonably slow frame rate. The final class also operates using the FMCW principle, but at 94 GHz, to produce high resolution 2D and 3D images out to about 50 m at a much higher update rate. These shorter range sensors may be used to determine the traversability of the local terrain. The outputs produced by the different classes of radar are examined and the paper considers their advantages when compared to other sensors such as vision and scanning laser. Using radar images, the final section compiles rules for interpreting radar reflectivity images from a path-planning perspective. © 2006 Wiley Periodicals, Inc. [source] Potential-based path planning for robot manipulatorsJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 6 2005Chien-Chou Lin In this paper, a potential-based path-planning algorithm for a high DOF robot manipulator is proposed. Unlike some c-space-based approaches, which often require expensive preprocessing for the construction of the c-space, the proposed approach uses the workspace information directly. The approach computes, similar to that done in electrostatics, repulsive force and torque between objects in the workspace. A collision-free path of a manipulator will then be obtained by locally adjusting the manipulator configuration to search for minimum potential configurations using that force and torque. The proposed approach is efficient because these potential gradients are analytically tractable. Simulation results show that the proposed algorithm works well, in terms of computation time and collision avoidance, for manipulators up to 9 degrees of freedom (DOF). © 2005 Wiley Periodicals, Inc. [source] 2D map-building and localization in outdoor environmentsJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 1 2005R. Madhavan Determining the pose (position and orientation) of a vehicle at any time is termed localization and is of paramount importance in achieving reliable and robust autonomous navigation. Knowing the pose it is possible to achieve high level tasks such as path planning. A new map-based algorithm for the localization of vehicles operating in harsh outdoor environments is presented in this article. A map building algorithm using observations from a scanning laser rangefinder is developed for building a polyline map that adequately captures the geometry of the environment. Using this map, the Iterative Closest Point (ICP) algorithm is employed for matching laser range images from the rangefinder to the polyline map. Once correspondences are established, an Extended Kalman Filter (EKF) algorithm provides reliable vehicle state estimates using a nonlinear observation model based on the vertices of the polyline map. Data gathered during field trials in an outdoor environment is used to test the efficiency of the proposed ICP-EKF algorithm in achieving the localization of a four-wheel drive (4WD) vehicle. © 2005 Wiley Periodicals, Inc. [source] A New Immune Genetic Algorithm and Its Application in Redundant Manipulator Path PlanningJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 3 2004Xiaoping Luo In this paper, first the immune system is analyzed in a relatively deeper and all-sided point of view reflecting the fresh research in biology. Second, based on the previous statements, a new optimization method, the immune genetic algorithm (IGA), is presented by simulating the behavior of the biological immune system and is proved to converge to the global optimum with probability 1. Third, a new method on the multi-object optimization that is transformed into a single-object one is proposed based on the joints' best compliance in the redundant robot path planning using IGA. Last, the experiment results show that the method of this article behaves more successfully. © 2004 Wiley Periodicals, Inc. [source] Introducing Radius of Torsure and Cylindroid of TorsureJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 8 2003David B. Dooner Robotic path planning can involve the specification of the position and orientation of an end-effector to achieve a desired task (e.g., deburring, welding, or surface metrology). Under such scenarios the end-effector is instantaneously rotating and translating about a unique axis; the ISA. Alternately, the performance of direct contact mechanisms (viz., cam systems and gear pairs) are dependent on the surface geometry between two surfaces in direct contact. Determination of this geometry can entail the parametrization of a family of geodesics curves embedded within each surface. This parametrization is tantamount to an end-effector rotating and translating about an ISA. In both scenarios there is a unique ISA for each geodesic embedded in a surface. Here, curvature and torsion of a spatial curve are coupled together to define an alternative definition for the radius-of-curvature of a spatial curve. This new definition is identified as radius of torsure to distinguish it from the classical definition for radius-of-curvature. Further, it is shown that the family of twists that corresponds to the pencil of geodesics coincident with a point on a surface defines a cylindroid: the cylindroid of torsure. An illustrative example is provided to demonstrate this difference. © 2003 Wiley Periodicals, Inc. [source] Using OXSIM for path planningJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 8 2001Stephen Cameron We address the issue of building scalable and reusable path planners for realistic robot manipulators working in three-dimensional space amid complex geometry, by presenting the latest version of our robot manipulator planning toolbox, OxSIM. OxSIM is designed to greatly simplify the building of planners by providing core competence in three-dimensional geometry. This is done by the provision of efficient routines for computing the distance between parts of the robot and its environment. A new version of OXSIM, written in C++, provides an object-oriented interface to the basic system, which increases its ease of use. Here we give an overview of OxSIM and how it works and describe a modified version of the probabilistic road map planner that we have implemented under the framework. © 2001 John Wiley & Sons, Inc. [source] MPK: An open extensible motion planning kernelJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 8 2001Ian Gipson The motion planning kernel (MPK) is a software system designed to facilitate development, testing, and comparison of robotic and geometric reasoning algorithms. Examples of such algorithms include automatic path planning, grasping, etc. The system has been designed to be open and extensible, so that new methods can be easily added and compared on the same platform. © 2001 John Wiley & Sons, Inc. [source] A new potential field method for mobile robot path planning in the dynamic environmentsASIAN JOURNAL OF CONTROL, Issue 2 2009Lu Yin Abstract A new potential field method for mobile robot path planning is proposed in this paper. At present, most potential field methods are designed to be applied in the stationary environment, and several improved potential functions have brought in the velocity factors in the dynamic circumstances. Based on the consideration that the moving trend of the robot in the dynamic environments is also necessary to produce more reasonable path, this paper defines new attractive potential function with respect to the relative position, velocity, and acceleration between the robot and the goal, as well as the repulsive potential function with respect to the relative positions, velocities, and accelerations between the robot and the obstacles. The virtual forces are calculated to make the robot plan its motion, not only with right positions, but also with suitable velocities. Furthermore, the robot will keep a similar moving trend with the goal and contrary trends with the obstacles. Finally, some methodic simulations are carried out to validate and demonstrate the effectiveness of the new potential field method. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [source] | ||||||||||