基于运动学分析的工业机器人轨迹精度测量的研究

机器人关节伺服系统的动态误差,是影响其末端执行器运动轨迹精度的一个重要因 素．本文以六轴关节型激光加工工业机器人为研究对象,采用D-H方法建立起机器人连杆坐 标系,在运动学分析的基础上,运用齐次坐标变换矩阵微分法,建立机器人各关节转角的偏 差值与末端运动轨迹精度之间的模型,并在此基础上,利用机器人与外部的串口通讯,对在 关节伺服系统影响下,沿各种空间位置运动时,机器人末端运动的轨迹精度进行了实际测量 ．     

面向工业机器人系统的三种可靠度配置策略的研究

工业机器人的可靠性决定着它的应用前景及质量,而我国的工业机器人的可靠性并不容乐观,急需加以提高,针对这种情况,本文给出了三种有效的面向不同系统要求的工业机器人系统可靠度配置策略:"最小努力及比例"分配法适用于首次研制出来、已投入使用并准备进行产品生产,进一步提高其可靠度的工业机器人系统;"混联"分配法是一种简便易行的工业机器人系统可靠度分配方法,此方法适用于在无约束条件下进行研制新型工业机器人时,对其进行的系统可靠度分配,使得所研制的工业机器人具有较高的可靠性;"两级优化"分配是在有约束条件下的一种可靠度优化分配方法.这三种工业机器人配置策略的研究作为其可靠性设计中一个关键环节,不仅具有理论研究价值,同时具有重大的现实意义.     

A method for analytically generating three-dimensional isocomfort workspace based on perceived discomfort

The purpose of this study was to develop a new method for analytically generating three-dimensional isocomfort workspace for the upper extremities using the robot kinematics. Subjective perceived discomfort scores in varying postures for manipulating four types of controls were used. Fifteen healthy male subjects participated in the experiment. The subjects were asked to hold the given postures manipulating controls for 60 s in the seated position, and to rate their perceived discomfort during the following rest of 60 s using the magnitude estimation. Postures of the upper extremities set by shoulder and elbow motions, types of controls, and left right hand were selected as experimental variables, in which the L32 orthogonal array was adopted. The results showed that shoulder flexion and adduction-abduction, elbow flexion, and types of controls significantly affected perceived discomfort for postures operating controls, but hand used for operating controls did not. Depending upon the types of controls, four regression models predicting perceived discomfort were presented. Using the models, a sweeping algorithm to generate three-dimensional isocomfort workspace was developed, in which the robot kinematics was employed to describe the translational relationships between the upper arm and the lower arm/hand. It is expected that the isocomfort workspace can be used as a valuable design guideline when ergonomically designing three-dimensional workplaces.     

A collaborative behavior-based approach for handling ambiguity, uncertainty, and vagueness in robot natural language interfaces

Service robots are used by ordinary people in their houses and offices. For such users, a desirable way to communicate with robots is through natural language interfaces. So far, techniques for developing robot natural language interfaces are far from mature. A major challenge is handling ambiguity, uncertainty, and vagueness in parsing, object resolution, and vague natural language words. In this research, we develop a new approach called the collaborative behavior-based approach, in which behaviors of robots and behaviors of human users, as well as the changes of object states caused by the behaviors, are taken into consideration integratedly in processing natural language user instructions. In this paper, we analyze the special features of a human–robot interface that may affect language understanding, describe our approach that is designed based on the features, and present the implementation and some experimental results.     

A dynamics formulation of general constrained robots

The complexity of a standard compact-in-form Lagrangian dynamical expression is proportional to the fourth power of the number of degrees of freedom (DOF) of a robotic system. This fact challenges both simulation and control of robots with hyper degrees of freedom. In this paper, a systematic approach for deriving the dynamical expression of so-called general constrained robots is proposed. This proposed approach has two main features. First, it uses the subsystem dynamics such as the dynamics of joints and rigid links to construct the dynamical expression of the entire robotic system in a closed form. The complexity of the resulted dynamic expression is linearly proportional to the number of DOF of a robotic system. Second, it extends the standard dynamical form and properties of the conventional single-arm constrained robots to a class of more general robotic systems including the coordinated multiple-arm robotic systems. Three spaces, namely the general joint space, the general task space, and the extended subsystems space, are connected through corresponding velocity/force mapping matrices.An erratum to this article can be found at     

Olfactory coordinated area coverage

This paper proposes an olfaction based methodology to automatically cover an unknown area enabling the decoupled cooperation of a group of floor cleaning mobile robots. This method is based on the utilisation of low cost chemical sensors in cleaning mobile robots, in order to differentiate clean from dirty areas. The experimental results show that the use of olfactory capabilities allows to efficiently cover and clean a certain area, and demonstrate the possibility of coordinating several mobile robots without the need of expensive sensing capabilities, map building or complex algorithms for task scheduling.     

A Model-based Integration and Testing Method to Reduce System Development Effort

New methods and techniques are needed to reduce the very costly integration and test effort (in terms of lead time, costs, resources) in the development of high-tech multi-disciplinary systems. To facilitate this effort reduction, we propose a method called model-based integration. This method allows to integrate formal executable models of system components that are not yet physically realized with available realizations of other components. The combination of models and realizations is then used for early analysis of the integrated system by means of validation, verification, and testing. This analysis enables early detection and prevention of problems that would otherwise occur during real integration, resulting in a significant reduction of effort invested in the the real integration and test phases. This paper illustrates how models of components, developed for model-based integration, can be used for automated model-based testing, which allows time-efficient determination of the conformance of component realizations with respect to their requirements. The combination of model-based integration and model-based testing is practically illustrated in a realistic industrial case study. Results obtained from this study encourage further research on model-based integration as a prominent method to reduce the integration and test effort.     

磁阻传感器在机器人玩具中的应用

磁阻传感器是方向控制系统的核心部件，考虑到成本因素，获得一个高精度高稳定性的解决方案具有一定的难度。本文的实际工作背景是机器人玩具控制器设计的一部分，介绍了磁阻传感器的电路设计以及工作原理。控制芯片采用89C2051单片机．传感器是Honevwell公司的两轴磁阻微电路芯片HMC1022．以ADC0832作为模数转换芯片．使用I／O模拟了PWM输出，把处理所得的结果传递给主控制芯片。已在实际中使用，且获得了满意的效果。     

一种通过模糊自调整应用于机械手广义力/位置控制的稳定系统研究

提出一种基于模糊自调整的机械手控制结构,并针对机械手与外界环境接触时产生的作用力,定义了一种广义力,它是机械手执行机构输出力与机械手末端受到外界力的合力。那么,就可以用类似于机械手位置控制的方法达到力/位置控制目的,通过模糊自调整方法实现。在机械手受到的外力是有界限的前提下,考虑机械手非线性、耦合和多变量的动态特征,证明了整个闭环系统是全局稳定的。     

格语法在工业机器人中的应用

工业机器人的一个发展趋势是具备良好的人机界面,而自然语言理解控制将是最理想的人机接口技术。本文以自然语言理解技术中的格语法为理论基础,结合工业机器人的特点,提出了一种有效的汉语句子分析算法。通过应用于装配机器人,验证该算法的可行性。