西安理工大学学者 刘凯教授

刘凯,男,汉族,生于1957年11月,陕西西安人,工学博士,教授,博士生导师。1978—1982年在陕西机械学院机械系学习,获学士学位;1986—1989年在陕西机械学院机械系机械工程专业学习,获硕士学位;1996—1997年在日本国近畿大学理工学部进行合作科研工作并攻读博士学位,2003年     

机械学研究进展与发展趋势

机械学作为机械科学中的基础部分对机械工程的发展至关重要.本文从各个分支方向对近年来机械学的重要研究进展进行了总结概述,并介绍了机电一体化、微机械学等机械学发展的新方向,同时对未来机械产品及其研发ⅱ制造行业的一些重要发展趋势进行了展望.     

庆祝华北工学院建校60周年——人民兵工第一校

华北工学院原名太原机械学院,是一所多科性高等理工科院校,座落在太原市风光秀丽的二龙山下、汾水河畔学院路,与古晋阳八景之一的“冽石寒泉”和汉代古迹窦大夫祠相毗邻,占地约1500亩．     

机器人系统仿真及应用

本文首先介绍机器人系统仿真技术的发展概况及其主要应用，然后介绍所研制的机器人仿真系统ＴＨＲＯＢＳＭ，着重介绍它的原理、结构、功能和特点。     

磁性液体密封结构中漏磁的研究

为了研究磁性液体密封结构几何参数的变化对漏磁场的影响规律,选取不同的密封间隙、极齿宽度、齿槽宽度、齿槽深度及密封级数建立物理模型,用有限元方法计算各模型的漏磁场.结果表明在密封结构的轴向和径向距离上存在某一临界值,在临界值的两侧,漏磁场磁感应强度随密封结构几种几何参数的变化趋势不同:在轴向距离大于临界值时,轴向漏磁场磁感应强度随间隙的增大而增大,随级数的增加而减小,随齿宽的增大而减小,随槽宽和槽深的增大而增大;在径向距离小于临界值时,径向漏磁场磁感应强度随间隙的增大而减小,随级数的增加而增大,随齿宽的增大而增大,随槽宽的增大而增大,随槽深的增大而减小;径向距离大于临界值时的情况与小于临界值时的情况刚好相反.     

物种种性漂移研究

给出了物种种性漂移的定义，分析了物种机械学种性漂移，生物学种性漂移，遗传学种性漂移，气候学种性漂移和农艺学种性漂移的成因，提出了用于界定物种种性漂移的算术分析法和统计分析法，并用之对水稻单穗粒重性状因播期影响而发生的漂移进行了界定，还就诸如针对钟性漂移所应采取的对策等问题进行了讨论。     

履带车辆综合传动数字控制换挡

通过对履带车辆综合传动装置电液换挡要求进行分析,设计了兼有换向和调压功能的电液数字换挡系统,通过建模获得了由先导电磁阀和双边节流滑阀组成的数字调压阀的特性. 在此基础上针对综合传动装置单元件切换和双元件切换换挡过程特点制定换挡过程自适应控制策略并设计了换挡控制器. 试验结果表明,数字控制换挡改善了重型履带车辆综合传动装置离合器滑摩过程,提高了换挡平顺性,更好地满足了车辆对换挡品质和环境使用的要求.      

In-plane load measuring technique for the strength test of MEMS micro-cantilever

An in-plane load measuring technique is developed to perform the strength test of the micro-cantilever. Based on electromagnetism theorem, Micro UTM (Universal Testing Machine) was in-house made with the load range ±1 N and the displacement range ±300 μm. It applies an in-plane load on the free-end of the micro-cantilever. The load acts as a bending moment for the root of the cantilever, but as a torque for the anchor. The results show that for samples with different sizes the ultimate loads range from 1.3 to 69.8 mN and the calculated torque is ap-proximately proportional to the square of the bonding length. Two failure modes, fracture at the root of the cantilever and fracture at the anchor, are observed by micro examination to the debris, which indicates that there is a critical design to achieve the strength bal-ance between the cantilever and the anchor. The work demonstrates that Micro UTM is a powerful in-strument for the strength test of the micro-cantilever and similar micro-structures.     

Research on Cam-linkage Mechanism of Automatic Piecing Device

The principle of an automatic piecing device is presented, and the mathematic model of a specific combined mechanism of the automatic piecing device is analysed. The kinematics and dynamics equation of the combined mechanism is established on the basis of the mathematic model. By the virtual prototype technology, the motion of this mechanism is simulated, whose result is post-processed by ADAMS. To improve the output motion, according to the simulation output and automatic piecing device＇s practical working condition, the optimisation of the cam mechanism is carried out by finite difference method. The simulation result of this combined mechanism turns out in accordance with its theoretical analysis of virtual prototype in this research, which, therefore, lays a principle basis for the further study of automatic piecing device.