共查询到20条相似文献,搜索用时 15 毫秒
1.
Naoki Mizuno Kazunori Ohno Ryunosuke Hamada Hiroyoshi Kojima Jun Fujita Hisanori Amano 《Advanced Robotics》2013,27(14):687-698
The firefighting robot system (FFRS) comprises several autonomous robots that can be deployed to fire disasters in petrochemical complexes. For autonomous navigation, the path planner should consider the robot constraints and characteristics. Specifically, three requirements should be satisfied for a path to be suitable for the FFRS. First, the path must satisfy the maximum curvature constraint. Second, it must be smooth for robots to easily execute the trajectory. Third, it must allow reaching the target location in a specific heading. We propose a path planner that provides smooth paths, satisfy the maximum curvature constraint, and allows a suitable robot heading. The path smoother is based on the conjugate gradient descent, and three approaches are proposed for this path planner to meet all the FFRS requirements. The effectiveness of these approaches is qualitatively and quantitatively evaluated by examining the generated paths. Finally, the path planner is applied to an actual robot to verify the suitability of the generated paths for the FFRS, and planning is applied to another type of robot to demonstrate the wide applicability of the proposed planner. 相似文献
2.
A novel path-planning algorithm is proposed for a tracked mobile robot to traverse uneven terrains, which can efficiently search for stability sub-optimal paths. This algorithm consists of combining two RRT-like algorithms (the Transition-based RRT (T-RRT) and the Dynamic-Domain RRT (DD-RRT) algorithms) bidirectionally and of representing the robot–terrain interaction with the robot’s quasi-static tip-over stability measure (assuming that the robot traverses uneven terrains at low speed for safety). The robot’s stability is computed by first estimating the robot’s pose, which in turn is interpreted as a contact problem, formulated as a linear complementarity problem (LCP), and solved using the Lemke’s method (which guarantees a fast convergence). The present work compares the performance of the proposed algorithm to other RRT-like algorithms (in terms of planning time, rate of success in finding solutions and the associated cost values) over various uneven terrains and shows that the proposed algorithm can be advantageous over its counterparts in various aspects of the planning performance. 相似文献
3.
In this paper we propose a real-time search algorithm called Real-Time Target Evaluation Search (RTTES) for the problem of
searching a route in grid worlds from a starting point to a static or dynamic target point in real-time. The algorithm makes
use of a new effective heuristic method which utilizes environmental information to successfully find solution paths to the
target in dynamic and partially observable environments. The method requires analysis of nearby obstacles to determine closed
directions and estimate the goal relevance of open directions in order to identify the most beneficial move. We compared RTTES
with other competing real-time search algorithms and observed a significant improvement on solution quality. 相似文献
4.
Introducing Climax: A novel strategy to a tri-wheel spiral robot 总被引:1,自引:0,他引:1
This paper describes a prototype and analytical studies of a tri-wheel spiral mobile robot. The robot can reach any desired point with a sequence of rotational movements. The robot has a simple actuation mechanism, consisting of three wheels mounted on a platform with axes fixed in 120° and a motor connected to each. Our approach introduces several new features such as simple repeated sequence of commands for steering and spiral motion, versus direct movement to target. The mathematical model of the robot is discussed, and a steering method is developed to achieve full motion capabilities. For a number of missions, it is shown experimentally that the proposed motion planning agrees well with the results. 相似文献
5.
I. Troch 《Journal of Intelligent and Robotic Systems》1989,2(1):1-28
For a given continuous path, the problem of designing a time-optimal time-parametrization is considered. First, algorithms are presented which, under rather mild assumptions, yield the exact solution within two computational steps consisting of a forward and a backward computation. Then, the problem of quasi-continuous robot motion is investigated in detail. An algorithm of the same type results, but the computational burden is considerably reduced by making appropriate use of the special structure of the problem. By this, on-line use becomes feasible.Work supported by Oesterreichischer Fonds zur Foerderung der wissenschaftlichen Forschung. 相似文献
6.
针对移动机器人在动态环境中常遇到的非最优路径问题,提出了基于混沌反控制并具有一定预测能力的路径规划算法。算法结合神经网络和距离传播模型,无需先验知识并且能适应动态不确定环境。通过在关键位置控制机器人进行混沌运动,可以减少等距情况下随机选择所造成的非最优路径出现的几率。在目标振荡运动且速度快于机器人的情况下,通过分析目标的轨迹和方向可以预测目标的短期运动趋势,进而实现有效追踪。仿真结果表明该算法对于减少非最短路径和路径中的尖点具有一定的作用,对于追踪速度较快的目标也有较大的成功率。 相似文献
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基于侦察蚁和觅食蚁协作的机器人路径规划算法 总被引:1,自引:0,他引:1
根据对真实蚂蚁的最新研究成果,提出了一种全新的机器入路径规划蚂蚁算法.该算法由两组侦察蚁采用最近邻侦察搜索策略相向搜索出一条较优路径,再由一组觅食蚁通过在该路径附近觅食实现对该路径的优化,从而得到一条优化的路径.计算机仿真实验结果表明,算法收敛速度提高显著,且在障碍物非常复杂的地理环境,也能迅速规划出最优或基本最优的路径,效果令人满意. 相似文献
9.
不确定环境下移动机器人目标搜索问题中,目标在观测点被发现的概率常被设为理想的均匀分布,其路径优化指标通常为最短距离,但最短距离路径不等同于最优期望时间路径.针对此问题,本文提出了一种以期望时间为优化指标的概率多目标搜索算法.针对观测点的访问顺序不同会导致期望时间不同的现象,采用分层式路径优化策略.首先,构造一个新的非均匀目标分布概率测算模型;然后,在上层序列规划中,采用改进的改良圈算法生成期望观测点序列;最后,在下层特征地图的观测点间可行路径规划中,采用改进的快速随机生成树算法(GBC–RRT).实验结果表明:本文所提方法可显著缩短移动机器人目标搜索的期望时间,且能在目标不确定、非均匀分布的工作空间中得到最优期望时间的搜索路径. 相似文献
10.
视觉移动机器人的模糊智能路径规划 总被引:1,自引:0,他引:1
The path planning problem for intelligent mobile robots involves two main problems:the represent of task environment including obstacles and the development of a strategy to determine a collision-free route.In this paper,new approaches have been developed to solve these problems.The fairst problem was solved using the fuzzy system approach,which represent obstacles with a circle.The other problem was overcome through the use of a strategy selector,which chooses the best strategy between velocity control strategy and direction control strategy. 相似文献
11.
针对应用遗传算法进行移动机器人全局路径规划时遇到的早熟收敛和收敛速度慢等问题,提出一种基于定长二进制路径编码方式的改进遗传算法。研究此编码方式下的改进遗传操作,采用比例阈值自适应((N+K,N)+N)双种群进化策略,有效提高了算法收敛速度和全局寻优能力。仿真实验表明了该算法的有效性。 相似文献
12.
This work concerns studies on the primary problem of whether a material handling task to be executed by two collaborating robot arms is kinematically possible. For any task, the configuration of the two endeffectors at all instants must be reachable from the viewpoint of the joint variables which must remain within the range of their allowable limits. In other words for any task to be executable the object held by the two endeffectors is limited to move only inside a working envelope. The associated working envelope depends on the two robot arms as well as the object, and their relative geometry, that is, the orientation of the object and the way it is held by the two endeffectors. In fact, this envelope is the function of the specifications of the triplet.
For a pair of arms carrying an object four different tasks can be considered; for two of these the possibility of a desired motion is investigated. Such a study will verify the feasibility of a task, or will determine the required changes to be made in order to make it feasible. 相似文献
13.
Most algorithms in probabilistic sampling-based path planning compute collision-free paths made of straight line segments lying in the configuration space. Due to the randomness of sampling, the paths make detours that need to be optimized. The contribution of this paper is to propose a basic gradient-based algorithm that transforms a polygonal collision-free path into a shorter one. While requiring only collision checking, and not any time-consuming obstacle distance computation nor geometry simplification, we constrain only part of the configuration variables that may cause a collision, and not entire configurations. Thus, parasite motions that are not useful for the problem resolution are reduced without any assumption. Experimental results include navigation and manipulation tasks, eg a manipulator arm-filling boxes and a PR2 robot working in a kitchen environment. Comparisons with a random shortcut optimizer and a partial shortcut have also been studied. 相似文献
14.
移动机器人路径规划可分为两种类型:(1)全局路径规划;(2)局部路径规划。本文分析了Kohonen神经网络算法及其识别机理,提出了Kohonen神经网络和BP神经网络结合起来进行路径规划的方法,最后给出了具体的算法,探讨了在神经网络技术中引入学习机制的特点。 相似文献
15.
一种移动机器人的路径规划算法 总被引:10,自引:0,他引:10
本文提出一种移动机器人路径规划最短切线路径算法。依据此算法,机器人能顺利地避开障碍物到达目标位置,其原理简单,计算快捷,容易实现。仿真结果验证了它的有效性和实用性。 相似文献
16.
Makespan minimized multi-agent path planning (MAPP) requires the minimization of the time taken by the slowest agents to reach its destination. The resulting minimax objective function is non-smooth and the search for an optimal solution in MAPP can be intractable. In this work, a maximum entropy function is adopted to approximate the minimax objective function. An iterative algorithm named probabilistic iterative makespan minimization (PIMM) is then proposed to approximate a makespan minimized MAPP solution by solving a sequence of computationally hard MAPP minimization problems with a linear objective function. At each iteration, a novel local search algorithm called probabilistic iterative path coordination (PIPC) is used to find a sufficiently good solution for each MAPP minimization problem. Experimental results from comparative studies with existing MAPP algorithms show that the proposed algorithm strikes a good tradeoff between the quality of the makespan minimized solution and the computational cost incurred. 相似文献
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18.
The optimum motion planning in joint space (OMPJS) for robots, which generally consists of two subproblems, optimum path planning and optimum trajectory planning, was considered as a whole in the paper. A new method for optimum motion planning problem based on an improved genetic algorithm is proposed, which is more general, flexible and effective. This approach incorporates kinematics constraints, dynamics constraints, and control constraints of robotic manipulator. The simulation results for a two and a three degrees of freedom robots are presented and discussed. The simulations are based on genetic algorithm class library WGAClass 1.0 developed by us with Borland C++ 3.1. 相似文献
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20.
Considering robot systems in the real world, a multirobot system where multiple robots work simultaneously without colliding
with each other is more practical than a single-robot system where only one robot works. Therefore, solving the path-planning
problem in a multirobot system is very important.
In this study, we developed a path-planner based on the rapidly exploring random tree (RRT), which is a data structure and
algorithm designed for efficiently searching for multirobot box-pushing, and made experiments in real environments. A path
planner must construct a plan which avoids the robot colliding with obstacles or with other robots. Moreover, in some cases,
a robot must collaborate with other robots to transport the box without colliding with any obstacles. Our proposed path planner
constructs a box-transportation plan and the path plans of each robot bearing the above considerations in mind.
Experimental results showed that our proposed planner can construct a multirobot box-pushing plan without colliding with obstacles,
and that the robots can execute tasks according to the plan in real environments. We also checked that multiple robots can
perform problem tasks when only one robot could not transport the box to the goal.
This work was presented in part at the 13th International Symposium on Articifial Life and Robotics, Oita, Japan, January
31–February 2, 2008 相似文献