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61.
In this paper, Hamilton’s principle is employed to derive Lagrange’s equations of an liquid crystal display (LCD) glass-handling robot driven by a permanent magnet synchronous motor (PMSM). The robot has three arms driven by two timing belts. The dynamic formulations can be expressed by one and four independent variables, which are named as the rigid and flexible models, respectively. In order to verify the dynamic formulation is correct, we reduce the flexible model to the rigid one under some assumptions. In this paper, we adopt the real-coded genetic algorithm (RGA) to identify all the parameters of the robot and PMSM simultaneously. It is found that the RGA can identify system parameters which are difficult to be measured in practical problems, for examples, the inductance, stator resistance, motor torque constant, damping coefficient of the motor and timing belts. In numerical simulations, vibrations due to flexibility of the timing belts are investigated for the angular displacements, speeds, accelerations of arms, and the horizontal and vertical displacements of the robot. The angular displacements of the robot arm and the translational positions of the robot end are obtained in the numerical simulations and experimental results. From their comparisons, it is demonstrated that identification results of the dynamic model with four independent variables present the better matching with experimental results of the system.  相似文献   
62.
针对现有气动式机器人力控末端执行器存在力控精度低和响应慢等缺点, 提出一种非对称气电混合式力控末端执行器, 采用变参数PID控制器对非对称气缸的气动力与永磁直线同步电机的电磁力进行协调控制, 实现机器人连续接触式作业中接触力的实时补偿与精确控制. 通过对气动系统、永磁电机和控制器等进行建模与仿真分析, 研究其控制特性与力-位移特性. 仿真结果表明, 相比气动力控系统, 气电混合式力控系统可有效消除摩擦力与跟随误差等引起的滞环和爬行现象, 控制特性最大误差由9.2N(2倍最大静摩擦力+动静摩擦力差值)减小至1N, 其力-位移特性最大误差由9.6N(2倍动摩擦力+气动力波动)也减小至1N, 提高了力控精度, 可提升机器人连续接触式作业质量.  相似文献   
63.
In this paper the general dynamical equations were given for multibodiesmanipulator.The system is a topologic tree structure consisting of arbitrary number ofrigid bodies.The hinges allow the rotational and/or tranlational motion.Inconsideration of influence of friction the dynamic equations are established by meansof Newton-Euler’s method.Further,the equations are separated by way ofconstructing the distribution matrices and a group of force and motion equations areobtained.  相似文献   
64.
针对室内导航的环境特点,提出了一种简单快速的、以踢脚线为参考目标的移动机器人室内导航方法。该方法从图像中提取踢脚线作为参考直线,通过两条直线在图像中的成像特征,提取角度和横向偏离距离作为移动机器人的状态控制输入,从而实现移动机器人的横向运动控制。该方法无需进行摄像机的外部参数标定,大大简化了计算过程,提高了视觉导航的实时性。  相似文献   
65.
IntroductionTraceplanningisanimportantaspectinthecontrolofrobot.Accordingtothedemandofproduction,positionandattitudetraceofro...  相似文献   
66.
对传统的广义达朗贝尔运动方程作了两点推广:1)考虑含有移动关节的情形;2)把方程的适用范围由单链系统推广至树形系统。  相似文献   
67.
In this paper we introduce three enhancements for evolutionary computing techniques in social environments. We describe the use of the genetic algorithm to evolve communicating rule-based systems, where each rule-based system represents an agent in a social/multi-agent environment. It is shown that the evolution of multiple cooperating agents can give improved performance over the evolution of an equivalent single agent, i.e. non-social, system. We examine the performance of two social system configurations as approaches to the control of gait in a wall climbing quadrupedal robot, where each leg of the quadruped is controlled by a communicating agent. We then introduce two social-level operators&2014;speciation and symbiogenesis&2014;which aim to reduce the amount of knowledge required a priori by automatically manipulating the system&2018;s social structure and describe their use in conjunction with the communicating rule-based systems. The reasons for implementing these kinds of operators are discussed and we then examine their performance in developing the controller of the wall-climbing quadruped. We find that the use of such operators can give improved performance over static population/agent configurations.  相似文献   
68.
The paper describes the mechanical design of a parallel manipulator for motions of pure translation, whose kinematic analysis has shown very good performances such as a large workspace and small overall dimensions of the mobile platform; in particular, the “Cartesian” structure of the machine allowed to obtain constant accuracy and kinematic properties throughout the workspace. The structural design has minimized the mass of the moving links and, by the combined use of FEM and multibody codes, allowed to take into consideration the high stresses coming from inertial forces and to evaluate a-priori the resulting dynamic properties. A physical prototype has just been built in order to validate the developed models and assess the actual robot performances in real operating conditions. The present research has been partially co-funded by the Italian Ministry of Research and University and by the Polytechnic University of Marche under PRIN03 project “Design and prototyping of application-oriented mini-PKM”.  相似文献   
69.
新型智能球罐焊接机器人视觉传感器的研究   总被引:3,自引:0,他引:3  
孙振国  王军波  陈强  纪萌 《光学技术》2001,27(3):252-254
为实现智能球罐焊接机器人的自主运动与焊缝自动跟踪 ,研制了一种新型视觉传感器。该传感器以高分辨率线阵 CCD芯片为核心 ,由光源、滤光片、透镜等光学系统及 CCD驱动电路、光电信号处理电路等组成 ,其中光电处理电路全部由硬件实现。整个视觉传感系统可以避免焊接时弧光的干扰 ,实时、准确地检测出焊缝轨迹线偏差信号 ,具有实时性强、鲁棒性好、成本低、重量轻等优点。借助所研制的视觉传感器 ,球罐焊接机器人能够实现沿焊缝的自主运动和焊炬与焊缝的自动对中 ,满足球罐多层多道焊接工艺要求 ,实现球罐焊接作业的智能化、自动化  相似文献   
70.
柔性杆柔性铰机器人动力学分析   总被引:7,自引:1,他引:6  
研究由N柔性杆和N柔性铰组成的空间机器人的动力学问题.把柔性铰简化成一个线性扭转弹簧,采用假设模态法表示杆件的弹性变形,运用Kane方法对全柔机器人进行动力学建模,推导出完整的系统动力学方程组.通过一个数值仿真算例,验证所做工作的可行性,并分析了柔性效应对机器人动力学响应的影响.  相似文献   
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