基于遗传算法优化的机器人模糊控制系统

本文提出一种基于遗传算法优化的模糊控制系统并将之用于五自由度关节型机器人轨迹跟踪控制,该系统将五关节的位置误差和误差变化率作为模糊控制器的输入,输出为五关节的转矩,同时采用先进的遗传算法在线优化调整控制器参数,既避免建立复杂的机器人数学模型,又能达到精确的控制效果.仿真结果表明该控制系统用于机器人轨迹跟踪控制具有很好的性能,较好地实现了机器人的实时智能控制,并大幅提高了其控制的自适应性和鲁棒性,最后给出相关的实验和结论.     

双轮自平衡机器人行走伺服控制算法

为解决双轮自平衡机器人行走伺服控制问题,针对其动力学特性,提出使用分层模糊控制的方法对双轮自平衡机器人运动进行控制,并且设计一种基于mamdani型模糊推理规则的模糊控制器.使用这种模糊控制器在双轮自平衡机器人硬件平台上完成了2个实验.一是以恒定倾斜角行走为控制目标的行走伺服控制;二是以恒定速率行走为控制目标的行走伺服控制.实验结果表明,设计的模糊控制器模糊规则简洁,可以很好地解决双轮自平衡机器人行走伺服控制问题.     

基于遗传模糊控制的多机器人避碰规划

设计了一种基于遗传算法优化的模糊逻辑控制的多机器人避碰规划方法,采用简化的三层行为结构:躲避机器人、躲避静态障碍物和趋向目标点,三个行为分别独立推理,将不同传感器信息作为输入,机器人动作作为输出,再通过优先级和加权的方法对三个行为输出进行综合.随后,针对模糊控制中构造全部的模糊规则比较复杂的问题,采用遗传算法对模糊规则的隶属度函数宽度和中心值进行优化,实现模糊控制器的离线自寻优,得到一组最优参数.从最终的仿真效果看,通过遗传算法优化提高了机器人的自导航性能.     

未知环境中移动机器人实时导航与避障的分层模糊控制

为了解决单模糊控制器的“规则库爆炸”问题,设计了一种分层的模糊控制器,用于指导移动机器人通过未知环境到达指定的目标点．控制器根据8个超声传感器的信息和目标相对于机器人的方位确定机器人的运动．首先,每个超声传感器的信息被输入到危险度模糊控制器（DFC）中,产生关于周围环境中障碍物危险度的模糊向量．这些模糊向量经过融合与归一化处理后分别输入到上层的速度模糊控制器（VFC）和角速度模糊控制器（RFC）的推理机中．VFC根据目标的距离和障碍物的危险度控制机器人的前进速度．RFC根据目标的方向和障碍物的危险度控制机器人的转向,并采用最大隶属度法的反模糊化策略解决“对称不确定”问题．仿真与实验结果证明了所设计的模糊控制器简单而有效．     

空调管道清扫机器人控制系统的研究

目前,中央空调管道清扫已经越来越引起人们的重视,对空调管道进行定期清扫,可有效改善室内空气质量,并能够实现节能的目的;首先介绍了空调通风管道清扫机器人总体系统设计,然后对机械车体和监控系统进行设计,提出了多组态控制工作模式;机器人车体控制系统以单片机C8051F020控制核心,对管道清扫机器人行走和转弯策略进行了设计与测试,采用模糊PID控制调节电机转速,结合感知传感器信息对电机协调控制,有效地实现了机器人直线行走和稳定转向。     

结合融合函数的双轮机器人二型模糊控制

针对双轮自平衡机器人的运动控制,设计了区间二型模糊逻辑控制器(T2FLC),提出函数融合的方法,解决模糊控制器规则繁杂的问题。首先对双轮机器人进行运动学建模,针对机器人的数学模型,设计双闭环二型模糊自适应PID控制器,分别控制机器人的直立平衡和行走速度。将机器人的反馈变量进行函数融合,简化T2FLC的模糊规则。对设计的控制器进行仿真,结果表明T2FLC比PID控制器具有更快的响应速度。进一步考虑输入扰动和机器人数学模型参数不确定对控制器的影响,仿真表明T2FLC具有更好的抗干扰能力和更强的鲁棒性。     

一种独轮机器人的滑模控制

针对一种由一个车轮驱动并控制前向平衡、并由电机驱动惯性轮形成反力矩来控制侧向平衡的独轮机器人系统,提出了一种分组分层滑模变结构控制方法.该方法根据机器人动力学模型特点,将系统看作两个单输入系统组合,并分别针对每个单输入系统设计分层滑模控制器,从而实现机器人的运动平衡控制.从理论上证明了各层滑动平面的渐近稳定性,并通过仿...     

柔性关节微操作机器人自适应模糊预测控制

对一种柔性关节微操作机器人系统提出了多输入多输出直接自适应模糊广义预测控制方法,此方法先基于机器人理论模型设计出广义预测控制器,再构造直接自适应模糊控制器逼近广义预测控制器,并用机器人视觉误差信息对控制器参数和广义误差向量估计值中的未知向量进行自适应调整,以增强对建模误差的鲁棒性,并证明了所设计的控制器可使微操作机器人跟踪时变参考轨迹时的广义误差估计值收敛到原点的小邻域内,以达到控制要求,仿真结果验证了此方法的有效性.     

基于模糊控制的电脑鼠行进速度的控制

本文基于电脑鼠机器人行进过程中的速度控制,将一体式红外线发射接收器探测到的电脑鼠与前方障碍物的距离,以及电机的即时速度作为输入,设计一个模糊控制器,根据输入变量的大小来调整模糊控制器的量化因子,从而自动调整模糊控制策略,输出加速度来控制机器人的行进速度。根据实验,使用模糊自适应控制的电脑鼠机器人性能得到了显著的提高,具有较强的鲁棒性。     

单关节跳跃机器人模糊自适应轨迹跟踪控制

研究关节型跳跃机器人轨迹跟踪优化控制问题,针对机器人系统时变、非线性的复杂特性,传统模糊控制和PID控制方法难以获得较好的控制性能,为解决控制系统中超调量大、振荡和控制精度不高等问题,提出传统PID控制与模糊自适应控制结合的控制策略.首先建立单关节跳跃机器人腾空相和站立相动力学方程,依据专家经验制定PID参数整定策略,结合传统PID控制方法和模糊自适应理论设计模糊自适应PID控制器.引入合理的跳跃机器人物理参数和虚拟目标轨迹进行仿真,结果表明,模糊自适应PID控制器具有可行性和有效性,为应用于实际控制系统优化提供了可靠依据.     

Target tracking using a hierarchical grey-fuzzy motiondecision-making method

This paper presents a hierarchical grey-fuzzy motion decision-making (HGFMD) algorithm, which is capable of integrating multiple sequential data for decision making and for the design of the control kernel of the target tracking system. The algorithm combines multiple grey prediction modules, each of which can estimate a suitable model from sequential sensory information for approximating the observed dynamic system for future-trend prediction and for decision making through a multilayer fuzzy logic inference engine. We have designed the HGFMD controller for a target tracking system and implemented it in our autonomous mobile robot. The HGFMD is compared with the conventional fuzzy logic controller, multilayer fuzzy controller, and the original grey-fuzzy controller developed previously in various target-tracking experiments. We demonstrated the high reliability of the HGFMD controller and tracking system even when encountering the uncertain status of slow sensory response time and the nonlinear motion behaviors of the target     

Hybrid fuzzy control of robotics systems

This paper presents a new approach towards optimal design of a hybrid fuzzy controller for robotics systems. The salient feature of the proposed approach is that it combines the fuzzy gain scheduling method and a fuzzy proportional-integral-derivative (PID) controller to solve the nonlinear control problem. The resultant fuzzy rule base of the proposed controller can be decomposed into two layers. In the upper layer, the gain scheduling method is incorporated with a Takagi-Sugeno (TS) fuzzy logic controller to linearize the robotics system for a given reference trajectory. In the lower layer, a fuzzy PID controller is derived for all the locally linearized systems by replacing the conventional PI controller by a linear fuzzy logic controller, which has different gains for different linearization conditions. Within the guaranteed stability region, the controller gains can be optimally tuned by genetic algorithms. Simulation studies on a pole balancing robot and a multilink robot manipulator demonstrate the effectiveness and robustness of the proposed approach.     

Application of Fuzzy Logic for the Solution of Inverse Kinematics and Hierarchical Controls of Robotic Manipulators

In this paper, hierarchical control techniques is used for controlling a robotic manipulator. The proposed method is based on the establishment of a non-linear mapping between Cartesian and joint coordinates using fuzzy logic in order to direct each individual joint. The hierarchical control will be implemented with fuzzy logic to improve the robustness and reduce the run time computational requirements. Hierarchical control consists of solving the inverse kinematic equations using fuzzy logic to direct each individual joint. A commercial Microbot with three degrees of freedom is utilized to evaluate this methodology. A decentralized fuzzy controller is used for each joint, with a Fuzzy Associative Memories (FAM) performing the inverse kinematic mapping in a supervisory mode. The FAM determines the inverse kinematic mapping which maps the desired Cartesian coordinates to the individual joint angles. The individual fuzzy controller for each joint generates the required control signal to a DC motor to move the associated link to the new position. The proposed hierarchical fuzzy controller is compared to a conventional controller. The simulation experiments indeed demonstate the effectiveness of the proposed method.     

Evolutionary Design of Fuzzy Logic Based Position Controller for Mobile Robot

This paper develops a fuzzy logic based position controller whose membership functions are tuned by genetic algorithm. The main goal is to ensure successful velocity and position trajectories tracking between the mobile robot and the virtual reference cart. The proposed fuzzy controller has two inputs and two outputs. The first input represents the distance between the mobile robot and the reference cart. The second input is the angle formed by the straight line defined with the orientation of the robot, and the straight line that connects the robot with the reference cart. The outputs represent linear and angular velocity commands, respectively. The performance of the fuzzy controller is validated through comparison with previously developed mobile robot position controller based on control Lyapunov functions (CLF). Simulation results indicate good performance of position tracking while at the same time a substantial reduction of the control torques is achieved.     

Emergent behaviors of a fuzzy sensory-motor controller evolved bygenetic algorithm

Recently, there has been extensive work on the construction of fuzzy controllers for mobile robots by a genetic algorithm (GA); therefore, we can realize evolutionary optimization as a promising method for developing fuzzy controllers. However, much investigation on the evolutionary fuzzy controller remains because most of the previous works have not seriously attempted to analyze the fuzzy controller obtained by evolution. This paper develops a fuzzy logic controller for a mobile robot with a GA in simulation environments and analyzes the behaviors of the controller with a state transition diagram of the internal model. Experimental results show that appropriate control mechanisms of the fuzzy controller are obtained by evolution. The controller has evolved wen enough to smoothly drive the robot in different environments. The robot produces emergent behaviors by the interaction of several fuzzy rules obtained.     

自主轮式机器人THMR－V的混合模糊逻辑控制

轮式机器人的控制问题是控制研究的关键问题之一，对高速自主导航的轮式机器人，控制器的实时性、精确性和鲁棒性要求很高．在本文中，根据PID控制和模糊逻辑控制的各自优点，将传统的PID控制与模糊逻辑控制结合起来，提出了一种混合模糊逻辑控制算法. 经实验检验，该算法具有很高的实时性、控制精度和鲁棒性，能够满足机器人高速自主导航的需要．     

Application of a hybrid controller to a mobile robot

This paper presents the application of a hybrid controller to the optimization of the movement of a mobile robot. Through hybrid controller processes, the optimal angle and velocity of a robot moving in a work space was determined. More effective movement resulted from these hybrid controller processes. The experimental scenarios involved a five-versus-five soccer game and a MATLAB simulation, where the proposed system dynamically assigned the robot to the target position. The hybrid controller was able to choose a better position according to the circumstances encountered. The hybrid controller that is proposed includes a support vector machine and a fuzzy logic controller. We used the method of generalized predictive control to predict the target position, and the support vector machine to determine the optimal angle and velocity required for the mobile robot to reach the goal. First, we used the generalized predictive control to predict the target position. Then, the support vector machine is used to classify the angle that must be followed by the mobile robot to reach the goal. Next, a fuzzy logic controller is designed to determine the velocity of the left and right wheels of the mobile robot. Thus generated, the velocity was optimized according to the measures obtained by the support vector machine. Finally, based on the optimal velocity of robot, the output membership function was modified. Consequently, the proposed hybrid controller allowed the robot to reach the goal quickly and effectively.     

Brief communication: Uniform ultimate boundedness of a fuzzy logic controlled industrial robot

This article addresses the proof of uniform ultimate boundedness of a fuzzy logic controller plus a computed torque control scheme applied to trajectory tracking control of robotic manipulators. Further improvement of the performance of this fuzzy logic control scheme is achieved through automatic tuning of a weight parameter α leading to a self‐tuning fuzzy logic compensator. Experimental results demonstrate the effectiveness of the computed torque and fuzzy compensation scheme, as well as the self‐tuning fuzzy logic controller, applied to an industrial CRS Robotics Corporation A460 robot during a trajectory tracking task. © 2001 John Wiley & Sons, Inc.     

Improved Image Based Visual Servoing with Parallel Robot

The position regulation problem of an eye-in-hand type of parallel robot based pointing systems (PRBPS) is considered in this paper. A fuzzy logic system is first designed to compensate for the uncertainties of the parallel robot and the uncertainty of the image Jacobian, then a hybrid controller (HC) including the image-based nonlinear controller and the adaptive supervisory fuzzy logic controller (ASFLC) is derived by using the Lyapunov direct method to realize the position regulation (PR). The stability of the closed-loop system in the Lyapunov sense is proven theoretically. The fuzzy scaling matrix is combined with the HC to improve the performance of the control system. The simulation results demonstrate that the PRBPS realizes PR with very good robustness to the parameter uncertainties, and the control input torques and settling time are reduce greatly in the case of large initial feature errors.