Aiming at the problem that the speed fluctuation of the manipulator with flexible joints is prone to occur, based on the PI control strategy, the pole configuration method is used to optimize the controller parameters, and then the vibration degree of the manipulator is reduced by improving the output speed accuracy. Firstly, the dynamic model of the flexible joint in the manipulator is established according to the double inertia model, and then the state space equation of the flexible joint is obtained through the mathematical expression of the dynamic model. Then, the transfer function from the motor speed to the motor electromagnetic torque is obtained according to the state space equation. Next, the PI control strategy based on pole configuration based on the same amplitude is used to optimize the controller parameters, and the influence of different pole parameters on the dynamic characteristics of the system is analyzed. Finally, in order to verify the effectiveness of the proposed control strategy, a numerical simulation experiment is carried out on the servo system of the flexible joint of the manipulator by using MATLAB, and a physical prototype control experimental platform of the flexible joint is built to carry out the output angle control experiment. Numerical simulation experiments and physical prototype control experiments show that the control strategy proposed in this paper can obtain good dynamic characteristics of the system by properly selecting the pole parameters. Compared with the traditional PI control strategy, it can improve the output speed control accuracy and suppress the vibration of the manipulator.

为了提升Q345钢的表面耐磨性和耐蚀性能,采用可编程逻辑控制器(PLC)控制激光熔覆工艺,以F60合金粉作为熔覆材料,制备了无Y2O3的涂层和添加Y2O3的涂层,对比分析了两种涂层的物相组成、显微组织、硬度、耐磨性能和耐腐蚀性能.结果表明,无Y2O3涂层和添加Y2O3涂层中都含有ɑ-(Fe,Cr)、ɑ-Fe、(Fe,Cr)7C3、γ-(Fe,Cr)和CrFeB相,且添加Y2O3涂层中还出现了Y2O3相;两种涂层都与Q345钢基体结合良好;添加Y2O3涂层的晶粒尺寸和二次枝晶臂间距都小于无Y2O3涂层,且添加Y2O3涂层枝晶区域的Fe和B元素含量低于无Y2O3涂层;相同涂层距离处,添加Y2O3涂层的硬度都高于无Y2O3涂层,且都明显高于基体;无Y2O3涂层和添加Y2O3涂层的耐磨性和耐蚀性都优于Q345钢基体,且添加Y2O3涂层的耐蚀性和耐磨性高于无Y2O3涂层,这主要与涂层中存在(Fe,Cr)7C3和CrFeB等硬质相、添加Y2O3涂层的晶粒和二次枝晶臂间距更加细小等有关.

针对电子装配机器人高速高精要求,提出一种能够利用柔性铰链变形补偿轴承摩擦死区,实现高精度定位运动的刚柔耦合关节SCARA机器人的概念设计,并建立考虑柔性铰链变形与机械臂一阶弹性变形的双柔性动力学模型.首先,设计一种刚柔耦合轴承的结构,通过轴承中柔性铰链的变形量主动补偿摩擦死区引起的定位误差;在每个关节处引入两个扭转弹簧,分别模拟柔性铰链和机械臂的弹性变形;其次,建立关节的摩擦模型以模拟关节摩擦环境;然后,使用拉格朗日动力学方法建立包含摩擦信息与振动信息的动力学模型.设计开环和闭环的数值仿真进行验证,结果表明该模型理论分析的有效性.

职业教育的理念是"以服务为宗旨,以就业为导向,以岗位能力培养为重点"。为了促进课程体系改革,推动机械制造与自动化专业的建设,进而全面了解本专业的市场需求、岗位指向,课程体系与专业人才的知识、技能等方面的问题,本文对机械制造与自动化专业课程设置、人才需求等情况进行调研,对课程建设的方向进行积极的探索,进而建立和完善专业人才的培养方案,健全实践技能培养的课程体系,为职业教育的发展提供参考依据。

随着国家经济的快速发展,机械制造业已成为支柱型产业,高职院校机械制造与自动化专业毕业生成为生产一线的紧缺人才,探讨符合社会发展实际的、符合机械制造与自动化专业情况的课程体系,对培养实用型、复合型、工程型机械制造与自动化专业人才具有十分重要意义。因此,构建出真正符合机械制造与自动化专业所需理论知识与实践技能的课程体系,是笔在所在学校,乃至其他高职院校相关专业所需要迫切解决的问题。

随着我国现代工业经济的发展,装备制造业生产一线急需大量能够解决生产技术难题的高素质、技能型人才,使得机械制造与自动化专业人才需求连续多年位于用人需求榜首。技术密集型生产要求这些岗位上的工作人员不仅具有宽广的知识面,还要具有高超的专业技能,因此,提高机械制造与自动化专业建设水平,优化课程体系,才能提升本专业的人才培养质量,扩大本专业在河南省乃至全国的影响和辐射作用。这既是学院发展的需要,更是提升河南省装备制造业国际竞争力的迫切需求。

For workflow management system,both security and convenient management are very important.First,the main secure problems of workflow management system are analyzed,and then,a new secure model is presented according to the special secure requirements of workflow management system.It combines digital sign technology and role-based access control to construct a security mechanism which ensures both safety and easy-to-management of workflow management system.Based on the model,a practical workflow management system was successfully developed by J2EE/Oracle9i/Bes6.5 and B/S technology.

<正>怎样管理和利用好有限的教育资源,充分发掘高职院校实训基地的潜力,是高职院校甚为关注的问题。有创新才有出路,有思路才有对策。研究高职院校实训基地的管理模式,无疑对加强高职院校实践教学有积极的

On the base of describing the meteor trail communication principle,an emergent communication network which is based on the meteor trail communications is proposed.After analysing on the characteristics of meteor trail whose transmit linking is discontinuous and electron density is low,the rationality of meteor-burst communications as the emergent communication network is explained.Furthermore,this emergent communication network has a very bright prospect in china.