共查询到20条相似文献，搜索用时 31 毫秒
1.
基于PSO和滚动优化的不确定环境下移动机器人动态路径规划 总被引：1，自引：0，他引：1
针对全局环境未知且存在动态障碍物情况下的移动机器人路径规划问题,本文提出了一种结合粒子群算法(PSO)和滚动优化策略的动态路径规划方法。通过在一系列移动空间窗口中进行在线规划来充分利用机器人实时测得的局部环境信息,并用粒子群算法求解每一个移动窗口内的最优路径。为及时躲避动态障碍物,提出了一种适用于动态未知环境下的适应度函数。仿真试验表明,该方法克服了现有局部路径规划方法的高复杂性的缺点,算法操作简单、具有全局寻优能力、收敛速度快、鲁棒性好,可以满足机器人在复杂的未知动态环境下路径规划的实时性要求。 相似文献
2.
In recent years, evolutionary and meta-heuristic algorithms have been extensively used as search and optimization tools in various problem domains, including science, commerce, and engineering. Ease of use, broad applicability, and global perspective may be considered as the primary reason for their success. The honey-bee mating process has been considered as a typical swarm-based approach to optimization, in which the search algorithm is inspired by the process of real honey-bee mating. In this paper, the honey-bee mating optimization (HBMO) algorithm is presented and tested with a nonlinear, continuous constrained problem with continuous decision and state variables to demonstrate the efficiency of the algorithm in handling the single reservoir operation optimization problems. It is shown that the performance of the model is quite comparable with the results of the well-developed traditional linear programming (LP) solvers such as LINGO 8.0. Results obtained are quite promising and compare well with the final results of the other approach. 相似文献
3.
传统的基于最小方差原理的反演结果依赖于初始模型选择,易陷入局部极小,针对以上问题,文章利用完全非线性反演方法-粒子群反演算法,对核磁共振探测地下水的数据资料进行反演解释,该算法具有操作简单,并行处理,不要求被优化的目标函数具有可微、可导、连续等性质的优点。将基本粒子群算法与模拟退火算法结合,加入非线性约束优化条件,使其适用于核磁共振探测地下水数据资料的反演解释。试验结果表明,混合粒子群反演算法反演结果精度较高,收敛速度较快,验证了粒子群优化算法在核磁共振反演应用中的可行性。 相似文献
4.
《Journal of The Franklin Institute》2023,360(6):4378-4398
Dynamic path planning for mobile robots is an urgent issue that needs to be solved because of the growing use of mobile robots in daily life and industrial operations. This work focuses on avoiding moving obstacles in dynamic situations. The computational effort required by some current algorithms makes them difficult to utilize for path planning in dynamic situations whilst the computational effort required by other methods makes them simple yet prone to local minima. In this paper, an improved simulated annealing (SA) algorithm for dynamic path planning is proposed. To reduce its computational effort, the initial path selection method and deletion operation are introduced. Simulation results show the improved SA algorithm outperforms other algorithms and provides optimal solutions in static and dynamic environments. 相似文献
5.
在三轴曲面加工中,曲面加工质量与刀位轨迹的质量有紧密联系。在使用当前的计算机辅助设计(CAD)/计算机辅助制造(CAM)集成软件生成刀位轨迹时,若仅采用通常的0.01mm公差,在加工时有可能出现表面凹坑、光洁度较差等缺点。为解决上述问题,提出一种基于网格均匀化的刀位轨迹优化方法,在Cimatron生成的加工刀位轨迹基础上,通过建立主导轮廓线并对不规则的点进行修正来降低相邻刀路倾斜度变化的程度;然后对同一条刀路上的刀位点进行光滑连续直线段的识别;再采用分段3次样条进行拟合,以提高同一刀路上的曲线光滑程度。仿真实验与实际加工实验表明,本方法可以消除原来存在的表面凹坑,有效地提高最终的表面加工质量。 相似文献
6.
结合模松弛SQP算法和强次可行方向算法思想,给出了初始点任意选取的新的拟强次可行方向算法。每步迭代,只需求解一个总有最优解的二次规划子问题来产生主搜索方向,引入一种新的非单调曲线搜索来产生步长,在较弱的条件下,可以得到算法的全局收敛性。 相似文献
7.
《Journal of The Franklin Institute》2022,359(11):5206-5230
In the existing efficient robust model predictive control (ERMPC) algorithms (see e.g. [14,31,32]), through offline optimization and online lookup table calculation, a fixed state feedback control law or a linear interpolated control law is applied to a system when the system state lies between two adjacent polyhedrons, which undoubtedly will result in conservativeness of the controller. Faced with this issue, an improved ERMPC algorithm is proposed in this paper, which considers the nonlinearity between the state feedback control laws with respect to polyhedrons and the norm distance from system state to origin, and can provide continuously variable state feedback control law varying with the state. First, a set of polyhedral parameters and their corresponding state feedback control law sequences are obtained offline by solving a set of LMIs optimization problems. Next, for each state feedback control law sequence, a nonlinear fitting function is established offline between the state feedback control law and its serial number. Then a simplified lookup table is constructed offline to save memory space and shorten online computation time of the controller. According to the simplified lookup table and information of the norm distance from system state to origin, we online establish the coordinate of current state in the nonlinear fitting curve for getting current feedback control law, which changes continuously with the state. The proposed ERMPC algorithm is successfully applied to an actual fast-responding linear one stage inverted pendulum (LOSIP) system to verify its effectiveness. 相似文献
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9.
The problem of efficiently approximating the tradeoff (Pareto-optimal) curve or set for optimization problems with two conflicting objectives is considered. In particular, a new method is proposed for computing a relatively small number of points to define an approximate representation of the tradeoff set. The efficiency of the method is established by showing the maximum number of points required to achieve a prescribed precision of approximation. Finally, a general algorithm embodying the method is outlined and analysed. 相似文献
10.
《Journal of The Franklin Institute》2017,354(11):4457-4480
Due to the hopeful application of gathering information from unreachable position, wireless sensor network creates an immense challenge for data routing to maximize the communication with more energy efficiency. In order to design the energy efficient routing, the optimization based clustering protocols are more preferred in wireless sensor network. In this paper, we have proposed competent optimization based algorithm called Fractional lion (FLION) clustering algorithm for creating the energy efficient routing path. Here, the proposed clustering algorithm is used to increase the energy and lifetime of the network nodes by selecting the rapid cluster head. In addition, we have proposed multi-objective FLION clustering algorithm to develop the new fitness function based on the five objectives like intra-cluster distance, inter-cluster distance, cluster head energy, normal nodes energy and delay. Here, the proposed fitness function is used to find the rapid cluster centroid for an efficient routing path. Finally, the performance of the proposed clustering algorithm is compared with the existing clustering algorithms such as low energy adaptive clustering hierarchy (LEACH), particle swarm optimization (PSO), artificial bee colony (ABC) and Fractional ABC clustering algorithm. The results proved that the lifetime of the wireless sensor nodes is maximized by the proposed FLION based multi-objective clustering algorithm as compared with existing protocols. 相似文献
11.
针对多目标车辆路径问题,研究了车载量、配送里程、混合时间窗等限制约束条件下,以最小配送费用和最少配送车辆数为目标建立多目标数学模型。在分析智能水滴算法求解类似离散问题时存在的局限性基础上,运用多种方式对其进行改进,并引入遗传算法选择、交叉及重组算子提高其性能,构建出两种改进智能水滴遗传混合算法,运用Solomon标准测试算例和实际算例进行验证。比较结果显示,改进后的混合算法能够有效解决离散问题,在持续寻优能力上较传统智能水滴算法和遗传算法更优；并且竞争选择改进智能水滴遗传混合算法求解算例效果最优。 相似文献
12.
A direct approach to path planning of a 2-DOFs (Degrees of Freedom) spherical robot based on Bellman?s dynamic programming (DP) is introduced. The robot moves in an environment with obstacles and employs DP to find optimal trajectory by minimizing energy and preventing obstacle collision. While other path planning schemes rely on pre-planned optimal trajectories and/or feedback control techniques, in this approach there is no need to design a control system because DP yields the optimal control inputs in a closed loop (feedback) form. In other words, after completing the DP table, the optimal control inputs are known for every state in the admissible region and the robot can move toward the final position without colliding with obstacles. This enables the robot to function well in semi- or even non-observable environments. Results from several simulated experiments show that the proposed approach is capable of finding an optimal path from any given position/orientation towards a predefined target in an environment with obstacles within the admissible region. The method is very promising compared to other path planning schemes. 相似文献
13.
针对高斯混合模型算法（GMM）对初始参数敏感、易陷入局部最优的问题,本文提出一种基于改进海洋捕食者算法优化的GMM算法（MMPA-GMM）。首先基于混沌序列和伪对立学习策略初始化种群,引入非线性收敛因子平衡MPA算法的全局与局部搜索,同时提出融入社会等级制度的位置更新策略;然后从搜索能力和收敛速度对改进的MPA进行分析;最后以S_Dbw指标作为算法的适应度函数,利用改进的MPA优化GMM算法的初始参数。实验结果表明,改进的MPA在4种测试函数上表现良好,并且MMPA-GMM算法对4个数据集的聚类效果均有改善,有效避免了GMM算法陷入局部最优的问题。 相似文献
14.
粒子群算法网络异常检测技术研究 总被引：1，自引：0，他引：1
提出了一种新的基于粒子群算法入侵检测方法模型。算法采用粒子群优化算法,有效地降低网络拓扑路径长度,通过优化算法来寻找聚类的中心。实验结果表明,提出的改进算法与传统的入侵检测算法相比,具有更好的入侵识别率和检测率。 相似文献
15.
《Journal of The Franklin Institute》2023,360(10):6929-6952
Self-driving vehicles must be equipped with path tracking capability to enable automatic and accurate identification of the reference path. Model Predictive Controller (MPC) is an optimal control method that has received considerable attention for path tracking, attributed to its ability to handle control problems with multiple constraints. However, if the data acquired for determining the reference path is contaminated by non-Gaussian noise and outliers, the tracking performance of MPC would degrades significantly. To this end, Correntropy-based MPC (CMPC) is proposed in this paper to address the issue. Different from the conventional MPC model, the objective of CMPC is constructed using the robust metric Maximum Correntropy Criterion (MCC) to transform the optimization problem of MPC to a non-concave problem with multiple constraints, which is then solved by the Block Coordinate Update (BCU) framework. To find the solution efficiently, the linear inequality constraints of CMPC are relaxed as a penalty term. Furthermore, an iterative algorithm based on Fenchel Conjugate (FC) and the BCU framework is proposed to solve the relaxed optimization problem. It is shown that both objective sequential convergence and iterate sequence convergence are satisfied by the proposed algorithm. Simulation results generated by CarSim show that the proposed CMPC has better performance than conventional MPC in path tracking when noise and outliers exist. 相似文献
16.
细菌觅食算法在求解水库优化调度问题时,以固定的步长进行趋向操作,同时以固定概率对细菌个体进行随机驱散操作,虽然可以一定程度上增加种群多样性,但是在进化后期容易使优秀的个体流失,影响算法的寻优质量。针对该问题,文章提出步长自适应调整和驱散概率自适应调整两项改进策略,根据算法进化程度和细菌个体的能量值动态调整趋向操作的步长和驱散操作的概率,使算法进化过程中尽量保证种群多样性的基础上,提高细菌个体的觅食能力,进一步促进算法达到局部搜索和全局优化之间的平衡。将改进的细菌觅食算法应用于乌江梯级水库群的联合优化调度问题,模拟结果表明:改进细菌觅食算法具有较强的全局寻优能力,适合求解梯级水库联合优化调度问题。 相似文献
17.
In this paper, a convex optimization algorithm is proposed to solve the online trajectory optimization problem of boost back of vertical take-off/vertical landing reusable launch vehicles. To achieve high-precision landing of launch vehicles, trajectory optimization of the boost-back flight phase considering the accuracy of entry is carried out, especially in emergencies. The trajectory optimization problem is formulated as an optimal control problem with minimum fuel consumption, and then it is transformed into a series of convex optimization subproblems, which can be solved by primal-dual interior-point method accurately and rapidly. During the transformation, flip-Radau pseudospectral discretization method, lossless convexification and successive convexification technology are applied. To drive the vehicle to predetermined entry points at the expected velocity, terminal constraints are expressed as orbital constraints of the endpoint in the boost-back flight phase. Considering the influence of Earth's rotation, the right ascension of the ascending node of the target orbit is updated according to the time and true anomaly at the end of the boost-back flight phase. Furthermore, the homotopy method is applied to the situation where there is no good initial guess when emergency happens. The algorithm presented in this paper performs well upon the simulation experiments of mission change and thrust decline. With good accuracy, high computational efficiency, and excellent robustness, the convex approach proposed has a great potential for onboard application in reusable launch vehicles and other space vehicles. 相似文献
18.
《Journal of The Franklin Institute》2022,359(12):6099-6122
With the fast development of the economy, marine activities are increasing. Due to the advantages of offshore cranes, they are widely used in marine production as effective transportation tools. As a matter of fact, the offshore crane works on the ship known as a typical noninnertial system, which is affected by the ship movement. To tackle this problem, we propose a time optimal trajectory planning method for the considered offshore crane. Specifically, to tackle the couplings between state variables, we show that the offshore crane system is differentially flat with the payload coordinates as the flat outputs. Based on this fact, the planning problems for the jib motion and the rope length are further converted into the planning problems for flat outputs. Then, in order to ensure the trackability of the planned trajectory and improve the safety, we consider a series of physical constraints including the jib luffing motion velocity and acceleration constraints, the rope length varying velocity and acceleration constraints, and the payload swing angle and angular velocity constraints, and then a time optimization problem is further formulated. By utilizing a bisection-based method, the optimal payload transportation time is obtained as well as the corresponding time optimal trajectories. As far as we know, it is the first time optimal trajectory planning method designed for offshore cranes to achieve the fast and accurate payload transportation as well as the payload swing elimination in earth-fixed frame. At last, the effectiveness of the proposed method is verified by simulation tests. 相似文献
19.
解决城市住区停车难问题与创造高质量住区环境是当今住区规划设计的关键所在。本文从对目前常用停车方式进行分析入手,对各种停车空间的环境设计要点进行了逐一研究。 相似文献
20.
《Journal of The Franklin Institute》2023,360(14):10433-10456
An effective approach is proposed for optimal control problems in aerospace engineering. First, several interval lengths are treated as optimization variables directly to localize the switching points accurately. Second, the variable intervals are usually refined into more subintervals homogeneously to obtain the trajectories with high accuracy. To reduce the number of optimization variables and improve the efficiency, the control and the state vectors are parameterized using different meshes in this paper such that the control can be approximated asynchronously by fewer parameters where the trajectories change slowly. Then, the variables are departed as independent variables and dependent variables, the gradient formulae, based on the partial derivatives of dependent parameters with respect to independent parameters, are computed to solve nonlinear programming problems. Finally, the proposed approach is applied to the classic moon lander and hang glider problems. For the moon lander problem, the proposed approach is compared with CVP, Fast-CVP and GPM methods, respectively. For the hang glider problem, the proposed approach is compared with trapezoidal discretization and stopping criteria methods, respectively. The numerical results validate the effectiveness of the proposed approach. 相似文献