一种改进蚁群算法的移动机器人快速路径规划算法研究

以Dijkstra算法求解移动机器人路径规划(mobile robot path planning,MRPP)问题已得到广泛的应用,但在复杂工况下无法保证求解的正确性和全局最优性.而基于蚁群算法的移动机器人路径规划模型,在一定条件下能可靠地获得全局最优解,但存在求解时间过长的问题.因此,提出一种结合Dijkstra算法和蚁群算法模型两者优势求解MRPP问题的融合优化方法,以实现在短时间内获得全局最优解的目标.首先,应用Dijkstra快速算法在机器人工作环境中粗略寻迹得到最短路径次优解,然后,在次优解路径附近进行工作环境的精确划分;最后,利用蚁群算法在次优解附近精确寻迹,使最终的寻迹结果无限逼近最短路径.仿真结果表明,该融合优化方法既克服了经典蚁群算法求解时间过长的缺点,又能无限逼近全局最优解,寻迹时间较蚁群算法可缩短90%以上.     

一种移动机器人的路径规划算法

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。     

一种室内环境下移动机器人的路径规划新算法

文章首先建立移动机器人对室内环境的全局模型,通过任务规划将全局目标分解为易于实现的多个子目标。然后针对每一个子目标,根据机器人边界圆直径构建一种改进的可视图,利用可视图和Dijkstra算法得到对子目标的全局路径,从而实现全局目标的路径规划。该算法简单,适于室内环境下移动机器人的实时导航系统。     

基于改进RRT算法的移动机器人路径规划方法

针对RRT（快速随机搜索树）算法在复杂环境下规划效率低,且规划的路径不平滑的问题,提出一种改进的RRT算法。首先引入一种全新的目标偏向采样策略,在均匀采样得到的随机点与目标点的连线上随机取一个点作为新的随机点进行树的扩展。其次对冗余路径节点进行剪枝处理,将路径起始节点与后续节点连线与障碍物进行碰撞检测,滤除无效的弯折路径。最后采用多项式插值的方法,依据节点的边界条件进一步对路径进行曲率平滑处理。通过仿真实验验证,论文算法不仅极大地提升了原算法的规划效率,而且在很大程度上优化了路径。     

一种改进的移动机器人全局路径规划算法

基于移动机器人的安全考虑，提出了一种改进的可视图法。该方法用尽可能远离障碍物的路径表示弧，先确定可能的路径点作为节点，然后考虑可能路径，建立结点间的弧，并用Dijkstra算法求出图中的最短路径。最后通过仿真研究表明，用文章提出的方法规划的路径可以达到或接近最优路径。     

基于松弛Dijkstra算法的移动机器人路径规划

在栅格环境建模方法的前提条件下,针对在较大规模、障碍物密集的工作环境中移动机器人难以进行实时路径规划的问题,利用栅格地图的结构特点提出一种松弛的Dijkstra算法。该方法首先采用四邻域搜索在线性时间内构建从源点到全局各点的曼哈顿距离势场,然后从目标点向源点进行八邻域搜索并返回一条无碰撞、近似最优路径。经过Matlab仿真实验证实该方法在计算时间上比采用堆排序实现的Dijksta算法和A-star算法快10倍以上,在路径长度上与最短路径相比误差处于合理范围之内。     

基于粒子群算法的移动机器人路径规划

提出一种分步路径规划方法,首先采用链接图建立机器人工作空间模型,用Dijkstra算法求得链接图 最短路径;然后用粒子群算法对此路径进行优化,得到全局最优路径.仿真结果表明:所提方法简便可行,能够满足 移动机器人导航的高实时性要求,是机器人路径规划的一个较好方案.􀁱     

一种移动机器人全局路径规划新型算法

针对模拟退火算法收敛速度慢这一缺陷，提出了一种基于共轭方向法和模拟退 火算法相结合的新型混合优化算法，并成功应用于机器人神经网络路径规划中．该算法可以 使优化解不陷入局部极值解而得到全局最优解．仿真实验研究表明：本文提出的这种新型混 合优化算法，计算简单，收敛速度快，显著提高了求解移动机器人全局最优化问题的计算效 率．     

基于改进粒子群算法的移动机器人路径规划

为了提高复杂环境下移动机器人的精准导航作用,提出了移动机器人路径规划的改进粒子群优化(PSO)算法,即利用粒子个体极值的加权平均值,同时加入惯性权重.建立了移动机器人工作环境的栅格模型,利用Matlab软件进行移动机器人路径规划仿真分析.仿真结果表明:改进后的粒子群算法容易使粒子移动到最佳位置,加强了全局寻优能力,在复杂环境中搜索路径性能优于传统算法.     

A learning fuzzy algorithm for motion planning of mobile robots

A sensor-based fuzzy algorithm is proposed to navigate a mobile robot in a 2-dimensional unknown environment filled with stationary polygonal obstacles. When the robot is at the starting point, vertices of the obstacles that are visible from the robot are scanned by the sensors and the one with the highest priority is chosen. Here, priority is an output fuzzy variable whose value is determined by fuzzy rules. The robot is then navigated from the starting point to the chosen vertex along the line segment connecting these two points. Taking the chosen vertex as the new starting point, the next navigation decision is made. The navigation process will be repeated until the goal point is reached.In implementation of fuzzy rules, the ranges of fuzzy variables are parameters to be determined. In order to evaluate the effect of different range parameters on the navigation algorithm, the total traveling distance of the robot is defined as the performance index first. Then a learning mechanism, which is similar to the simulated annealing method in the neural network theory, is presented to find the optimal range parameters which minimize the performance index. Several simulation examples are included for illustration.     

改进A*算法的移动机器人最短路径规划

针对复杂室内环境下移动机器人路径规划存在实时性差的问题,通过对Dijkstra算法、传统A^*算法以及一些改进的A^*算法的分析比较,提出了对A^*算法的进一步改进的思路。首先对当前节点及其父节点的估计路径代价进行指数衰减的方式加权,使得A^*算法在离目标点较远时能够很快地向目标点靠近,在距目标点较近时能够局部细致搜索保证目标点附近障碍物较多时目标可达;然后对生成的路径进行五次多项式平滑处理,使得路径进一步缩短且便于机器人控制。仿真结果表明,改进算法较传统A^*算法时间减少93.8%,路径长度缩短17.6%、无90°转折点,使得机器人可以连续不停顿地跟踪所规划路径到达目标。在不同的场景下,对所提算法进行验证,结果表明所提算法能够适应不同的环境且有很好的实时性。     

A path following algorithm for mobile robots

This paper considers path following control for a robotic platform. The vehicle used for the experiments is a specially designed robotic platform for performing autonomous weed control. The platform is four-wheel steered and four-wheel driven. A diesel engine powers the wheels via a hydraulic transmission. The robot uses a Real Time Kinematic Differential Global Positioning System to determine both position and orientation relative to the path. The deviation of the robot to the desired path is supplied to two high level controllers minimizing the orthogonal distance and orientation to the path. Wheel angle setpoints are determined from inversion of the kinematic model. At low level each wheel angle is controlled by a proportional controller combined with a Smith predictor. Results show the controller performance following different paths shapes including a step, a ramp, and a typical headland path. A refined tuning method calculates controller settings that let the robot drive as much as possible along the same path to its setpoint, but also limit the gains at higher speeds to prevent the closed loop system to become unstable due to the time delay in the system. Mean, minimum and maximum orthogonal distance errors while following a straight path on a paving at a speed of 0.5 m/s are 0.0, −2.4 and 3.0 cm respectively and the standard deviation is 1.2 cm. The control method for four wheel steered vehicles presented in this paper has the unique feature that it enables control of a user definable position relative to the robot frame and can deal with limitations on the wheel angles. The method is very well practical applicable for a manufacturer: all parameters needed are known by the manufacturer or can be determined easily, user settings have an easy interpretation and the only complex part can be supplied as a generic software module.     

移动机器人的智能路径规划算法综述

针对目前移动机器人路径规划所处的的环境复杂度高、随机性强等情况,难以有效地实现最优路径规划的问题,从移动机器人的实际应用出发,对点对点路径规划和遍历路径规划、全局路径规划和局部路径规划进行综述,对各类规划方法进行分析与归纳;重点分析强化学习算法的路径规划技术;针对目前路径规划算法存在的问题,提出类脑智能算法应用于路径规划的探索,同时给出路径规划在农业装备应用的新思路.     

A path planning algorithm for industrial robots

Instead of using the tedious process of robot teaching, an off-line path planning algorithm has been developed for industrial robots to improve their accuracy and efficiency. Collision avoidance is the primary concept to achieve such goal. By use of the distance maps, the inspection of obstacle collision is completed and transformed to the configuration space in terms of the robot joint angles. On this configuration map, the relation between the obstacles and the robot arms is obvious. By checking the interference conditions, the collision points are indicated with marks and collected into the database. The path planning is obtained based on the assigned marked number of the passable region via wave expansion method. Depth-first search method is another approach to obtain minimum sequences to pass through. The proposed algorithm is experimented on a 6-DOF industrial robot. From the simulation results, not only the algorithm can achieve the goal of collision avoidance, but also save the manipulation steps.     

基于信息融合的移动机器人定位与路径规划

针对镜面反射引起的声呐测距不准的问题,设计一种加权融合的方法对声呐和摄像头的信息进行融合,使移动机器人能够精确地完成在拐角区域下的自身定位,并给出了机器人的路径规划。通过在先锋3机器人平台上进行的实验结果证明,该方法能够使移动机器人安全、平滑地通过拐角区域。     

A new multisensor fusion SLAM approach for mobile robots

This paper presents a novel method, which enhances the use of external mechanisms by considering a multisensor system, composed of sonars and a CCD camera. Monocular vision provides redundant information about the location of the geometric entities detected by the sonar sensors. To reduce ambiguity significantly, an improved and more detailed sonar model is utilized. Moreover, Hough transform is used to extract features from raw sonar data and vision image. Information is fused at the level of features. This technique significantly improves the reliability and precision of the environment observations used for the simultaneous localization and map building problem for mobile robots. Experimental results validate the favorable performance of this approach.     

A chaotic path planning generator for autonomous mobile robots

This work presents a chaotic path planning generator which is used in autonomous mobile robots, in order to cover a terrain. The proposed generator is based on a nonlinear circuit, which shows chaotic behavior. The bit sequence, produced by the chaotic generator, is converted to a sequence of planned positions, which satisfies the requirements for unpredictability and fast scanning of the entire terrain. The nonlinear circuit and the trajectory-planner are described thoroughly. Simulation tests confirm that with the proposed path planning generator better results can be obtained with regard to previous works.     

Dynamic path planning of mobile robots with improved genetic algorithm

In this study, a new mutation operator is proposed for the genetic algorithm (GA) and applied to the path planning problem of mobile robots in dynamic environments. Path planning for a mobile robot finds a feasible path from a starting node to a target node in an environment with obstacles. GA has been widely used to generate an optimal path by taking advantage of its strong optimization ability. While conventional random mutation operator in simple GA or some other improved mutation operators can cause infeasible paths, the proposed mutation operator does not and avoids premature convergence. In order to demonstrate the success of the proposed method, it is applied to two different dynamic environments and compared with previous improved GA studies in the literature. A GA with the proposed mutation operator finds the optimal path far too many times and converges more rapidly than the other methods do.     

Global path planning of mobile robots using a memetic algorithm

In this paper, a memetic algorithm for global path planning (MAGPP) of mobile robots is proposed. MAGPP is a synergy of genetic algorithm (GA) based global path planning and a local path refinement. Particularly, candidate path solutions are represented as GA individuals and evolved with evolutionary operators. In each GA generation, the local path refinement is applied to the GA individuals to rectify and improve the paths encoded. MAGPP is characterised by a flexible path encoding scheme, which is introduced to encode the obstacles bypassed by a path. Both path length and smoothness are considered as fitness evaluation criteria. MAGPP is tested on simulated maps and compared with other counterpart algorithms. The experimental results demonstrate the efficiency of MAGPP and it is shown to obtain better solutions than the other compared algorithms.