一种新的四自由度SCARA机器人手眼标定方法

针对四自由度机器人手眼标定精度不高的问题,提出了基于标定块的手眼标定系统.通过引入亚像素角点提取算法,提取特征点的精确像素坐标;结合机械手平移规则,完成手眼系统旋转矩阵的标定,通过标定块提取机器人第三连杆中心在工作平台上的投影点所对应的世界坐标,计算系统平移矩阵.实验表明:方法不仅提高了手眼系统标定精度,而且简化了特征点世界坐标的提取过程.     

FPGA-realization of the kinematics IP for SCARA robot

Microsystem Technologies - In the implementation of robot motion control, it often requires complex forward and inverse kinematics calculation. However, this algorithm requires more CPU time in the...     

SCARA机器人内模控制方法

为了使SCARA机器人在外界干扰和模型不精确的情况下具有优良的轨迹跟踪性能,提出一种基于内模控制原理设计SCARA机器人控制器的方法。采用拉格朗日方法获得SCARA机器人动力学模型,将其作为内模控制的估计模型;选择内模滤波器[f(S)]设计内模控制器[Q(S),]使其满足稳态误差为零的条件,通过推导得出不同输入信号下的SCARA机器人控制律。通过仿真,将其与自适应模糊滑模控制方法进行对比分析,结果表明所提出的方法轨迹跟踪精度高,抗干扰能力强,控制器参数调节简单。     

Universal compliant device based on SCARA concept

The paper presents the results of the research and the development of the universal adaptive compliant device for customary assembly task robot configurations. The developed system is based on a newly developed SCARA robotic mechanism and combined properties of the SCARA concept and RCC devices. It successfully operates around its true compliance center, obtained under precisely determined conditions.     

基于PMAC下SCARA机器人的PID参数调节

本文介绍了在使用美国Delta-Tau公司的PMAC控制卡对四轴SCARA机器人进行PID参数调节过程中所遇到典型问题，以及解决方法。     

视觉引导技术在SCARA机器人装配任务中的应用

基于实际生产项目,提出了一种针对平面关节型机器人(SCARA)平面装配任务的手眼标定方法。对线性标定法的输出通过多次迭代使得累积误差和逐渐减小,相较于使用线性标定法来进行手眼标定,视觉定位的平均定位误差降低了0. 4 mm,最大定位误差降低了0. 6 mm。在使用SCARA机器人进行毫米(mm)级作业时,使用迭代线性标定法比传统的线性标定法有更高的视觉定位精度。同时,末端执行器完成对目标工件的抓取任务之后,使用解线性方程的思想求解SCARA机器人完成装配任务的末端位姿,通过实际工程项目的验证,装配成功率可达98. 6%。     

Simulation of a SCARA robot with PD and learning controllers

In this study, a SCARA robot manipulator is simulated under PD and learning based controllers. The trajectory following performance of the robot is studied against these controllers. The adaptive/learning hybrid controller scheme and learning controller method are utilized as learning based controllers. The results of simulations show that, learning algorithm based controllers reduce the position tracking error effectively. The hybrid adaptive/learning controller has similar performance as the learning controller although it uses partial state information and compensates both mechanical and electrical dynamics, whereas the learning controller needs both position and velocity measurements neglecting electrical dynamics.     

Three methodologies for the calibration of industrial manipulators: Experimental results on a SCARA robot

This article presents and compares three algorithms for the geometric parameter identification of industrial robots to increase its accuracy (static calibration). The estimation is based on the measure of the gripper pose errors when the robot follows suitable trajectories. The algorithms are general and can be applied to any robot providing that its kinematics is known. After a theoretical introduction to the general methodologies, these are applied to a selective compliance assembly robot arm (SCARA) robot analyzing its performance (precision, efficiency). Experimental results obtained with three methodologies are presented and discussed. The measure of the gripper pose error is based on a laser triangulation technique whose working principles are also recalled. © 2000 John Wiley & Sons, Inc.     

A concept for an intelligent and fault-tolerant robot system

A concept for the intelligent control of subsystems of a flexible assembly cell is presented. Unknown or uncertain data about the real world may lead towards failure during an assembly task. Therefore, a fault tolerant system must be capable of reacting immediately to error situations. Thus, the major topic of this paper is the dynamic handling of unforeseen situations during realtime activities. This will be achieved by combining sensor guided actions with an advanced autonomous supervision system. Experimental results will be derived from the mobile two-arm robot system KAMRO of the Institute for Real-Time Computer Control Systems and Robotics, University of Karlsruhe, Federal Republic of Germany.     

Teleoperation based on the hidden robot concept

Overlaying classical teleoperation control schemes based on a bilateral master-slave coupling, a teleoperation architecture designed in a general teleworking context is proposed. In this scheme, the executing machine is perceptually and functionally hidden to the operator by means of an intermediate functional representation between a real remote world and man. As any executing machine, and more particularly a robot, will be replaced by man, the image of the robot will not appear in the intermediate representation. This principle is thus named: “the hidden robot concept.” In this approach, the teleoperation problem is divided into two main parts: 1) choosing the appropriate intermediate representation and determining its interaction and relation with man and 2) building the relations and transformations between the intermediate representation and the real remote environment. The constituents of this teleoperator are outlined in this paper and an experiment validating this concept is presented     

Experimental and statistical determination of the static position repeatability and a recommended specification for a SCARA robot

This paper describes an experiment and the statistical analysis performed to evaluate the repeatability of a SCARA robot and proposes an alternative form of specification for repeatability. Repeatability has been chosen because the precision obtained from teach-and-play-back programming for pick-and-place tasks, which is still widely used, depends primarily upon this performance value. The measuring method uses two theodolites, which though laborious in set-up is nevertheless simple, economical and sufficiently accurate for the purpose intended. The results are used for comparison with the given specification and for studying the influence of factors such as load, speed and spatial location in the working envelope using analysis of variance; the estimate of the repeatability value is calculated using the standard deviations of the measured coordinates of representative points modified by a factor from Student's t curves. From the analysis, it can be inferred that the repeatability value is dependent upon operating speed, load and plane location. The experimental study also points to a possible form of specification. For example, for the specification to be useful in the study of arrangement of feeders of parts to be assembled by the robot and the estimation of throughput given part weight, it could be given in a table form showing the range of the repeatability value for the designed combinations of speed, payload and position in the envelope.     

A new approach for constructing the concept map

In recent years, e-learning system has become more and more popular and many adaptive learning environments have been proposed to offer learners customized courses in accordance with their aptitudes and learning results. For achieving the adaptive learning, a predefined concept map of a course is often used to provide adaptive learning guidance for learners. However, it is difficult and time consuming to create the concept map of a course. Thus, how to automatically create a concept map of a course becomes an interesting issue. In this paper, we propose a Two-Phase Concept Map Construction (TP-CMC) approach to automatically construct the concept map by learners’ historical testing records. Phase 1 is used to preprocess the testing records; i.e., transform the numeric grade data, refine the testing records, and mine the association rules from input data. Phase 2 is used to transform the mined association rules into prerequisite relationships among learning concepts for creating the concept map. Therefore, in Phase 1, we apply Fuzzy Set Theory to transform the numeric testing records of learners into symbolic data, apply Education Theory to further refine it, and apply Data Mining approach to find its grade fuzzy association rules. Then, in Phase 2, based upon our observation in real learning situation, we use multiple rule types to further analyze the mined rules and then propose a heuristic algorithm to automatically construct the concept map. Finally, the Redundancy and Circularity of the concept map constructed are also discussed. Moreover, we also develop a prototype system of TP-CMC and then use the real testing records of students in junior high school to evaluate the results. The experimental results show that our proposed approach is workable.     

A new concept in chair design

. What is to be expected from the office chair of the future? One thing is certain: office seating is taking on increasingly dynamic dimensions. Office work today is based on a multitude of activities requiring frequent changes in position, and added to this are flexible organizational forms—technically complex office systems are often used by a number of people. Thus, the working chair has become a prime target for an ergonomic approach in the office environment.     

Proposal for a new concept for a robot in which the constructing module can be exchanged seamlessly

Although industrial robots have developed considerably since the end of the last century, and have been used in various fields, robotics is still being actively researched in Japan. Following the work of national research institutes and educational institutions, robot manufacturers have also put considerable resources into developing a new generation of robots. Moreover, society in general has high expectations of robots. To provide a low-price robot that can be widely used in the home, in medical treatments, in welfare, and in disaster relief, etc., a high-function, low-cost module that can easily be exchanged for maintenance or repair is very necessary. To achieve this aim, it is undesirable to develop robots based on different original standards from research institutes, educational institutions, and robot manufacturers, etc. Therefore, a common standard in robotic development needs to be established, and robots must be developed based on that standard. In this research, a new concept for the next generation of robot development is proposed. This concept includes a high-intelligence module, lower manufacturing costs, and an easy exchange operation.     

A new concept of compatibility structure in new product development

Notwithstanding the existence of few publications addressing the compatibility issues in new product development, an axiomatic basis supporting this literature and driving new contributions to the subject is still lacking. In this paper, we propose a definition of a compatibility structure that lays down the foundations of an axiomatic basis for modelling compatibility in new product development. Regarding the number of conditions comprised in this definition, a minimal representation of compatibility structure is proposed to ease the use and manipulation of a compatibility structure. The definition of compatibility structure and its minimal representation are inspired by those of preference structure in preference modelling. The similarities and dissimilarities between preference structures and compatibility structures are emphasized. The construction and the characterization of a compatibility structure without incomparability using the proposed definition are provided. In this paper, we also propose a method to evaluate the crisp compatibility relations between two alternatives with respect to attributes/criteria. The compatibility relations are evaluated by investigating the impact that an alternative has on another, and vice-versa with respect to a single attribute/criterion. Future research related to the compatibility structure proposed in this paper is described.     

一种移动机器人路径规划新算法

快速搜索随机树（Rapidly-exploring random Tree Star,RRT*）算法在移动机器人实际应用中规划路径在转向部分存在较多的冗余转折点,导致移动机器人在移动转向过程中出现多次停顿与转向,为剔除规划路径中的冗余路径点,提高机器人移动流畅性,提出一种改进的 RRT*算法。算法将局部逆序试连法引入移动机器人路径规划,在确保RRT*算法概率完备性和渐进最优性的前提下,剔除规划路径中的冗余路径节点,使最终路径更加接近最短路径。通过MATLAB仿真实验证明,规划路径平均长度缩短4%,算法耗时缩短35%,改进后的RRT*算法能缩短规划路径且转向部分路径更加平滑。最后,使用改进后的RRT*算法在室内环境下进行移动机器人路径规划实验。实验结果表明：规划路径上无冗余路径点,且移动机器人沿路径移动流畅。     

一种用于拱泥机器人位姿检测的倾角传感器

基于霍尔效应的原理 ,为节杆式拱泥机器人研制了一种新型倾角传感器 ,详细介绍了原理结构 ,设计了信号处理和采集电路 ,并对传感器进行了初步测试。     

三支概念的一种构建方法

三支概念构建是三支形式概念分析的研究内容之一。为丰富三支概念的研究内容,利用矩阵结构,提出一种三支概念构建算法。首先,给出属性矩阵的定义,并设计利用属性矩阵构建属性三支概念的算法过程,对实例进行算法运算,以此对算法步骤进行说明,对算法正确性进行了相应验证。其次,定义对象矩阵,并设计依据此矩阵构建对象三支概念的算法,对实例进行算法运算。经上述研究验证,所提算法正确且有效。研究结果为三支概念在数据处理中的应用提供了更多选择。     

A new concept of invariance for saturated systems

In this paper, the notions of SNS-invariance and SNS-domain of attraction are introduced. The SNS-domain of attraction serves as an estimation of the domain of attraction of a saturated system. It is shown that, in the case of single input saturated systems, any contractive set is contained in the SNS-domain of attraction. Another important characteristic of the SNS-domain of attraction is that it contains any estimation obtained by means of a linear difference inclusion of the saturated system. A simple algorithm that converges to the SNS-domain of attraction is presented. An illustrative example is given.