An optimality criterion for a limited capacity queueing system

A single server, limited capacity queueing system with Poisson arrivals and exponential service is studied. The joint probability distribution of the number of times the system reaches its capacity in time interval (0t] and the number of customers in the system at time i has been obtained. From, the joint probability, the probability that the system has reached its capacity m times in time interval (0t] has been determined and the expectation and variance have been found explicitly. A criterion for the system to be optimum is established and is illustrated numerically.     

基于遗传算法的静态环境全局路径规划

静态环境中移动机器人全局路径规划一直是路径规划中的一个重要问题.作者提出了基于遗传算法的静态环境下机器人全局路径规划方法.该方法首先提出机器人工作空间中环境信息的神经网络模型,并利用该模型建立机器人免碰撞路径与神经网络输出的关系,然后将需规划的路径的二维编码简化成一维编码,并把免碰撞要求和最短路径要求融合成一个适应度函数.通过对算法进行实验仿真表明,提出的全局路径规划方法是正确和有效的.     

Control of the spatial motions of a gantry manipulator with elastic links

A mathematical dynamic model is proposed for a controlled gantry robot with elastic compliance and inertia distributed along a two-link arm. The model includes a nonlinear system of hybrid differential equations. Kinematic and dynamic control problems for the robot are formulated. The dynamic characteristics of the robot are analyzed in comparison with an equivalent model of a robot manipulator with rigid links based on the Lagrangian formalism __________ Translated from Prikladnaya Mekhanika, Vol. 42, No. 2, pp. 121–128, February 2006.     

An open-loop control scheme for minimization of residual vibrations of a flexible robot

The aim of this study is to develop a practical control scheme, called the three-step input method, whereby a flexible robot arm is moved from one position to another with a minimum of residual vibration when the arm reaches its defined endpoint. This work is concerned with defining a simple practical method to utilize step inputs to achieve optimum response. The optimum response is achieved by using a self-adjusting input command function that is obtained during real-time processing. The practicality of this control scheme is demonstrated by using an analog computer to simulate a simple flexible robot and conventional servo controller. The experiments focus on point-to-point movement. Also, this method required little computational effort through the intelligent use of conventional servo control technology and the robot's vibration characteristics.     

Fractional Order Control of a Hexapod Robot

This paper studies the performance of integer and fractional order controllers in a hexapod robot with joints at the legs having viscous friction and flexibility. For that objective the robot prescribed motion is characterized in terms of several locomotion variables. The walking performance is analysed through the Nyquist stability criterion and several indices that reflect the system dynamical properties. A set of model-based experiments reveals the influence of the different controller implementations upon the proposed metrics.     

一种新的三维测量机器人手眼标定方法

为了提高三维测量机器人的手眼标定精度以更好地满足工业需求,提出了一种采用动态改变变异率的自适应差异进化算法进行手眼标定的新方法。首先构建了由线结构光测头和机器人组成的视觉测量系统,利用齐次坐标变换的方法建立了测量系统的数学模型;然后针对数学模型中的手眼关系,使用半径已知的球体,采用定点变位姿的方法,进行粗略的估计,并对手眼关系求解的精度进行分析;最后采用动态改变变异率的自适应差异进化算法对手眼关系做进一步寻优。实验结果表明,算法具有较高的求解精度。该方法用于手眼标定是可行的、有效的,整个标定过程简单,便于实际应用。     

基于传感网络的水下机器人控制器设计

由于水下机器人在水下受到不定水流的干扰,机器人控制器缺陷较大。设备并实现了一种以传感网络配合模糊控制理论的水下机器人控制器。利用频率为20khz的超声波传感器网络组成控制器中的距离测量模块,对水下机器人测量方位和运动速度进行测量,给出了测距过程,主控模块以S3C2410嵌入式主控芯片为主,配合神经网络算法对障碍物进行判断,设计了详细的判断过程,提高机器人水下避障性能。以M3型水下机器人作为测试对象,测试结果说明控制器可以较高完成工作,达到应有水平。     

半被动双足机器人控制系统设计

为有针对性地根据不同干扰类型选择正确的抗干扰措施,有必要对无人机数据链所处环境的干扰信号进行分析和分类识别。本文以变换域通信系统(Transform Domain Communication System,TDCS)为载体,对无人机数据链常面临的干扰类型的自动识别进行研究,采用时域、频域、时频联合分析的方法,提出了一组对干信比变化不敏感的特征参数,并利用这组参数提出一种基于决策树理论的干扰分类识别方法,仿真结果表明,该方法能够快速准确地识别出干扰类型,具有很好的鲁棒性,并且在干信比和干噪比在0dB以上时,正确识别率均在90%以上。     

基于人工免疫改进的搬运机器人蚁群路径规划

针对搬运机器人在障碍环境下的路径寻优问题,提出一种基于人工免疫改进的蚁群路径规划算法(AI-ACA)。蚁群算法(ACA)的规划依赖于信息素挥发系数、期望启发因子和信息启发因子等参数的选取,传统ACA通过经验来设定这三个参数,但路径寻优中的最优参数因障碍环境而异,为解决经验参数对不同环境路径寻优结果的影响,引入人工免疫算法(AIA),对ACA的相关参数进行迭代优化,以此改善路径寻优结果。仿真结果及在自制机器人平台上测试表明,AI-ACA对于不同障碍环境可以准确地进行路径规划,在同样环境下较所参考的定参数蚁群路径规划效果有明显提升,提高了整个系统的运输效率。     

激光测距无损检测机器人运动控制研究

为了提高无损检测机器人行走的直线度,针对移动机器人系统,本文研究了激光测距的位置反馈方法,开发了基于微控制器STM32芯片的控制器,完成了边缘传感器信号、光电码盘信号、激光测距信号的接收与处理。设计了系统的软件结构,探讨了移动机器人系统的建模与仿真,详细分析了永磁同步电机的数学模型和移动机器人的运动学模型,在此基础上,以移动机器人的侧移与偏移角度为指标,设计PID控制器的参数,进行PID控制算法的仿真。经过仿真分析,研究扰动对于系统各部分新能的影响,验证了控制算法的合理性与有效性。