Path planning for robot using Population-Based Incremental Learning

The treatment of left turns at signalized intersections drives the development of signal phasing and timing plans and also plays an important role in overall traffic network operations. Accommodating left turns allows for the most direct routeing but reduces intersection capacity, whereas restricting left turns improves capacity but requires some vehicles to travel longer distances. This paper proposes a population-based incremental learning (PBIL) algorithm to determine at which intersections left-turn restrictions should be enacted to maximize a network's operational performance. The performance of each configuration is tested in a micro-simulation environment on both perfect and imperfect square grid networks. Comparison with a partial enumeration of feasible options reveals that the PBIL algorithm is effective at identifying a near-optimal configuration of left-turn restrictions. The resulting configurations suggest that left turns should be generally restricted at intersections that carry the most flow. These intersections typically occur in the central portion of the network when demands are relatively uniform. Doing so helps to provide additional intersection capacity at the locations where it is most necessary, while minimizing the additional travel distance that is incurred due to detours caused by the left-turn restrictions. These provide insight as to how urban traffic networks might be managed to improve network efficiency by only enacting left-turn restrictions at a subset of locations.

Performance evaluation of power system stabilizers based on Population-Based Incremental Learning (PBIL) algorithm

According to the realistic duty of robot, it's necessary to find a short path to avoid obstacles and carry limited goods, and then the added constrains let the problem is more complex and more practical. The paper proposes a tabu-genetic algorithm for robot path planning. By utilizing the main frame of parallel search supplied by genetic algorithm and embed the individual serial search mode of tabu search algorithm, this method can enlarge search space. And in order to enhance optimized speed and quality, also improve the algorithm performance, fitness function and amendatory policy are designed. Besides, algorithm convergence is analyzed based on the model of Markov chains. The results of simulations show that the method proposed in this paper, which can find an optimal path quickly and improve convergence speed and solution quality greatly.

A hybrid algorithm (HA) based on population based incremental learning (PBIL) algorithm and zooming algorithm (ZA) is proposed, and its convergence is proved in this paper. In the hybrid algorithm, PBIL algorithm is employed for the evolutionary process as it can accelerate the convergence speed by a reduced time complexity, zooming algorithm is used to improve the PBIL algorithm as it can reduce search space on a large scale, and develop the convergence speed and the precision of solution obviously. The convergent analysis shows that if the population is big, and the parameters are proper, the hybrid algorithm converges to the global optimal solution.

The population-based incremental learning (PBIL) is a novel evolutionary algorithm combined the mechanisms of the Genetic Algorithm with competitive learning. In this paper, the influence of the number of selected best solutions on the convergence speed of the PBIL is studied by experiment. Based on experimental results, a PBIL algorithm with elitist strategy, named Double Learning PBIL (DLPBIL), is proposed. The new algorithm learns both the selected best solutions in current population and the optimal solution found so far in the algorithm at same time. Experimental results show that the DLPBIL out-performs the standard PBIL. Both the convergence speed and the solution quality are improved.

Aiming at the problem of robot path planning in complex maps, an algorithm of robot path planning based on triangular grid graph is proposed. Firstly, a weighted undirected loop graph and a feasible domain of nodes are obtained by discretizing the triangular mesh map. Next, the Dijkstra search algorithm is applied to find the feasible shortest path from an initial to a final configuration. Finally, The Douglas-Peucker algorithm is applied to remove duplicate and redundant nodes in the feasible path, and the waypoint are extracted. The final path is a curve that is obtained by connecting the several extracted waypoint. The proposed algorithm is tested for various maps. Compared with probabilistic roadmap method, the experimental results show that the proposed method can overcome the shortcomings of the random sampling method. Furthermore, the experimental result of triangular mesh map method used in two labyrinth maps show that the triangular mesh map method can solve the robot path planning problem in complex map very well, and it is an excellent algorithm for robot path planning.

In this paper we study two different meta-heuristics to solve a real-word frequency assignment problem (FAP) in GSM networks. We have used a precise mathematical formulation in which the frequency plans are evaluated using accurate interference information coming from a real GSM network. We have developed an improved version of the scatter search (SS) algorithm in order to solve this problem. After accurately tuning this algorithm, it has been compared with a version fixed for the FAP problem of the population-based incremental learning (PBIL) algorithm. The results show that SS obtains better frequency plannings than PBIL for all the experiments performed.

Traffic supervision in telephone networks is a task which needs to determine streams responsible for call losses in a network by comparing their traffic values to nominal values. However, stream traffic values are not measured by the on-line data acquisition system and, hence, have to be computed. We perform this computation by inverting an approximate knowledge based model of stream propagation in circuit-switched networks. This inversion is computed thanks to three evolutionary computation techniques (multiple restart hill-climbing, population-based incremental learning and genetic algorithms) for which both a binary version and a real variant have been experimented with several fitness measures. The final results first point out how the fitness measure choice can impact on their quality. They also show that, in this case, real variants of the algorithms give significantly better results than binary ones.

The convergence analysis and specification of the Population-Based Incremental Learning algorithm

The authors previously (1994) showed that the potential field method combined with the navigating fuzzy logic controller (NFLC) can produce a safe and smooth paths for a robot. When the robot is trapped in undesired local minimum, the fuzzy tracking controller (FTC) can be employed to escape the trapping. Since the rules of the NFLC and the FTC is developed by expert's experiences, the learning of the rules is necessary to improve the performance. In this paper, an auto tuning technique called the cache genetic algorithm (CGA) is proposed to adjust the rules. The proposed CGA performs the fast operation of selection, crossover and mutation in a cache pool to obtain best fuzzy parameters. Computer simulations showed that the proposed fuzzy potential approach (FP) with the proposed cache genetic learning algorithm can improve the overall performance with fast tuning speed.

In view of high dimension, the difficulty of training, the problem of slow learning speed in the application of BP neural network in mobile robot path planning, an algorithm of reinforcement Q learning based on extreme learning machine (Q-ELM algorithm) is proposed in this paper. Firstly, the characteristic of reinforcement learning is combining the dynamic network with supervised learning, and the algorithm obtains the state information of the environment and the robot by the characteristic. After that, it is used to analyze the state to get the rewards and punishments of the current state by extreme learning machine. Secondly, it is used to solve the problem of slow training speed by the characteristic of less parameter settings and better generalization performance; Finally the autonomic learning performance of the learning algorithm is verified. The experimental results show that the Q-ELM learning algorithm not only improves the initiative of machine learning, but also improves the learning rate of 4 times than TD reinforcement learning methods, and verifies the stability and convergence of the algorithm.

A new ant algorithm for robot path planning is presented according to the latest achievements of research on actual ants. In this algorithm, m scout ants collaborate with each other to search for an optimal or near-optimal path. Of m scout ants, n ants adopt nearest-neighbor search strategy and the left q=m-n ants adopt random search strategy. A section of optimal path will be found after all ants search L steps. Then m ants regard the end point of as the new starting point and search for L steps to find the next section of optimal path . Repeat this process until one of m ants reaches the goal. In this way, the path is consisted of h sections of path with step length L. Carry out the next generation search after step length L is modified, then repeat the searching course mentioned above. An optimal or near-optimal path will be found through comparison after multi-generation of searching. The simulation experiment results show that an optimal or near-optimal path can be planned even in environment with very complex obstacles, which can meet the requirements of real-time planning or navigation. The effect is quite satisfying.

Development without any defect is unsubstantial. Timely detection of software defects favors the proper resource utilization saving time, effort and money. With the increasing size and complexity of software, demand for accurate and efficient prediction models is increasing. Recently, search-based techniques (SBTs) have fascinated many researchers for Software Defect Prediction (SDP). The goal of this study is to conduct an empirical evaluation to assess the applicability of SBTs for predicting software defects in object-oriented (OO) softwares. In this study, 16 SBTs are exploited to build defect prediction models for 13 OO software projects. Stable performance measures — GMean, Balance and Receiver Operating Characteristic-Area Under Curve (ROC-AUC) are employed to probe into the predictive capability of developed models, taking into consideration the imbalanced nature of software datasets. Proper measures are taken to handle the stochastic behavior of SBTs. The significance of results is statistically validated using the Friedman test complied with Wilcoxon post hoc analysis. The results confirm that software defects can be detected in the early phases of software development with help of SBTs. This paper identifies the effective subset of SBTs that will aid software practitioners to timely detect the probable software defects, therefore, saving resources and bringing up good quality softwares. Eight SBTs — sUpervised Classification System (UCS), Bioinformatics-oriented hierarchical evolutionary learning (BIOHEL), CHC, Genetic Algorithm-based Classifier System with Adaptive Discretization Intervals (GA_ADI), Genetic Algorithm-based Classifier System with Intervalar Rule (GA_INT), Memetic Pittsburgh Learning Classifier System (MPLCS), Population-Based Incremental Learning (PBIL) and Steady-State Genetic Algorithm for Instance Selection (SGA) are found to be statistically good defect predictors.

Evolutionary algorithms (EAs) have become the standards and paradigms for solving inverse problems. However, their two inherited operations, namely, the crossover and mutation operations, are complicated and difficult, both in theory and in numerical implementations. In this regard, increasing efforts have been devoted to EAs which are based on probabilistic models (EAPMs) to overcome the shortcomings of available EAs. The population-based incremental learning (PBIL) is an EAPM; moreover, it can bridge the gap between machine learning and the EAs, hence enjoying several merits compared with other EAs. However, lukewarm efforts have been devoted to PBILs, especially the real coded PBILs, in the study of inverse problems in electromagnetics. In this regard, a novel real coded PBIL is being proposed in this paper. In the proposed real coded PBIL, a probability matrix is proposed to randomly generate a population, and the updating formulas for this probability matrix using the so far searched best solution and the best solution of the current population are introduced to strike a balance between convergence performance and solution quality. The proposed real coded PBIL algorithm is numerically experimented on several case studies and promising results are reported in this paper.

This paper studies the obstacle avoidance and navigation of mobile robots in unstructured environments. Because of the shortcomings of one single sensor, the system integrates the stereo vision sensor blumblebee2 with the lidar sensor to detect the information surrounding the mobile robot’s surroundings. And then through data fusion to get a more complete, more accurate scene distribution. Then use the improved system of ant colony optimization to increase the convergence speed and precision of the algorithm in robot path planning. Finally, the simulation experiment is carried out in the environment of Matlab and Visual Studio, and the physical experiment is carried out under the ROS platform. The experimental results show the feasibility and effectiveness of the proposed method.