摘要：Non-contact actuated microbeads have attracted a lot of attention in recent years because of its enormous potential in medical, biological, and industrial applications. Researchers have proposed a multitude of electromagnetic actuation(EMA) systems consisting of a variety of coil pairs. However, a unified method to design and optimize a coil pair according to technical specifications still does not exist. Initially, this paper presented the modeling of an untethered ferromagnetic particle actuated by externally applied magnetic field. Based on the models, a simple method of designing and optimizing the EMA coil pair according to technical specifications, was proposed. A loop-shaped coil pair generating uniform magnetic and gradient fields was chosen to demonstrate this method clearly and practically. The results of the optimization showed that the best distance to radius ratio of a loop-shaped coil pair is 1.02 for a uniform magnetic field and 1.75 for a uniform gradient field. The applicability of the method to other shapes of coil configuration was also illustrated. The best width to distance ratio for a square-shaped coil pair is 0.558 and 0.958 for uniform magnetic and gradient fields, respectively. The best height to width ratio and distance to width ratio for a rectangle-shaped coil pair is h/w =[0.9,1.1], d/w =[0.5,0.6] for uniform magnetic field and h/w =[1.0,1.2], d/w =[0.9,1.1] for uniform gradient field. Furthermore, simulations of a microparticle tracking the targeted trajectory were conducted to analyze the performance of the newly designed coils. The simulations suggested the ability of manipulating microparticles via the coils designed by our proposed method. The research mainly proposed a unified design and optimization method for a coil pair, which can support researchers while designing a specific coil pair according to the technical requirements. This study is aimed at researchers who are interested in EMA system and microrobots.

摘要：The segment erector is a key part of the shield machines for tunnel engineering. The available segment erectors are all of serial configuration which is suffering from the problems of low rigidity and accumulative motion errors. The current research mainly focuses on improving assembly accuracy and control performance of serial segment erectors. An innovative design method is proposed featuring motion group-decoupling, based on which a new type of segment erector is developed and investigated. Firstly, the segment installation manipulation is analyzed and decomposed into three motion groups that are decoupled. Then the type synthesis for the 4-DOF motion group is performed based on the general function（GF） set theory and a new configuration of （1T？1R？1PS3UPS） is attained according to the segment manipulation requirements. Consequently, the kinematic models are built and the reducibility and accuracy are analyzed. The dexterity is verified though numerical simulation and no singular points appear in the workspace. Finally, a positioning experiment is carried out by using the prototype developed in the lab that demonstrates a 13.1% improvement of positioning accuracy and the feasibility of the new segment erector. The presented group-decoupling design method is able to invent new type of hybrid segment erectors that avoid the accumulative motion error of erecting.

摘要：为避免航空发动机喘振,高压压气机的可调静叶需要按照拟定的调节规律转动。静叶调节机构是驱动可调静叶转动的执行机构,一般采用多级联动调节的方式。由于拟定的静叶调节规律十分复杂,且多级静叶调节机构之间运动学耦合,静叶调节机构的尺度设计问题非常困难。目前一般采取逐级分解、单级优化的局部优化策略设计机构参数,无法获得全局最优的机构设计参数。为提高静叶调节精度,通过分析静叶调节机构运动学特点,提出正-逆运动学结合的机构尺度全局优化设计方法:先进行基于逆运动学解析解的全局、高效参数优化设计,再进行基于正运动学数值解的机构参数高精度优化求解,有效解决了静叶调节机构的全局尺度优化设计难题。通过案例分析,验证了所提设计方法的有效性和实用性。

摘要：砂模3D打印是一种快速发展的砂模智能制造技术,能够对任意复杂形体进行几何造型。在实际应用中,砂模造型设计仍沿用传统设计思想,尚未充分发挥3D打印所带来的技术优势。由于传统砂模几何形体中存在冗余结构,直接影响打印效率,因此有必要结合3D打印技术优势对砂模结构进行设计优化,以提高生产效率、节约生产成本。在新工艺环境下,本文建立了一种砂模结构优化设计方法及其设计流程;以砂模壁厚作为优化参数,依据力学性能要求,建立了砂模结构优化设计模型;最终基于某厂铸造试验件进行了范例设计与仿真校核。优化设计后的试验件砂模在满足力学性能要求的前提下,体积优化率达到42.6%,有效提升3D打印砂模的生产效率与经济性。

摘要：伺服冲压运动设计是伺服压力机实施伺服冲压作业的核心技术之一。提出NURBS运动曲线混合阶次插值方法,能任意给定冲压运动关键点上位置、速度或加速度中的一个或多个约束,以同时满足伺服冲压运动精确性和灵活性要求;提出快速生成给定时间的保压段冲压运动曲线算法;给出构造插值方程过程中合理设置切矢模长的取值方法,以避免运动曲线畸变;提出适当改变速度或加速度约束调节运动曲线性能的方法;在此基础上引入板料成形和伺服电动机驱动能力等约束,提出伺服冲压运动设计的一般流程,开发出交互式伺服冲压运动设计软件;以某型汽车翼子板拉深冲压运动设计为例进行了验证。

摘要：构型设计是机器人创新设计的重要阶段,考虑机构特性建立逻辑运算法则、从运动合成角度建立并联机器人构型设计方法,比较符合基于逻辑推理和形象思维、从无到有根据设计任务构造方案的设计需要。鉴于并联机器人的支链结构决定了末端转动特征的迁移能力,提出支链末端特征的实轴迁移定理和虚轴迁移定理。实轴迁移定理指支链末端的转动特征决定于支链中转动铰链的轴线位置,该转动特征沿移动特征方向具有迁移能力;虚轴迁移定理指支链末端的转动特征在与之垂直的末端移动特征平面上具有平行迁移能力,分6种不同情况采用虚设转动副法分别利用自由度分析加以证明。利用轴线迁移定理分析了两种新机构的末端转动特征。

摘要：太空桁架在轨装配目前主要依靠值守空间站的航天员完成,开展在轨智能装配作业是未来发展趋势。针对可拓展太空桁架的在轨智能装配问题,对前期所研制新型桁架结构进行装配信息定义,建立桁架装配体编码规则和数据结构,定量描述不同基本单元的特征差异、位姿差异与连接关系,实现杆件和多头球点两类基本单元的独立编号;基于机器人视觉装配作业要求,设计出一套用于存储和提取桁架装配信息的靶标系统,实现桁架基本单元编码与靶标ID之间的映射,将桁架组件的识别与装配信息的提取过程转化为靶标的识别与靶标映射表的检索过程。5 m直立桁架仿真算例验证了所提方法的可行性和有效性。

摘要：在分析研究了平底从动件凸轮机构中凸轮与从动件之间的油膜的动力性能的基础上，提出了把此油膜看成是存在于凸轮与从动件之间的一个质量—弹簧—阻尼系统的假设，建立了相应的动力学模型和运动微分方程，并运用弹流理论和凸轮机构动力学，对油膜厚度、油膜等效刚度和考虑油膜影响的平底从动件凸轮机构的动力响应进行了计算和分析，所得到的动力响应变化对于设计高速凸轮机构具有较大的实用价值。

摘要：现阶段机器人的智能和自主能力仍很薄弱,作业能力的提升、人机交互能力的改善和安全性能的提高是发展的首要目标,需要解决制约人-机交互、人-机合作、人-机融合发展的瓶颈问题,突破三维环境感知、规划和导航、类人的灵巧操作、直观的人-机交互、安全机器人行为等单元技术,建议我国采取发展战略:1加强工业机器人整机设计理论与方法研究,寻求新思维,突破精密减速机、控制器、伺服系统以及高性能驱动器等核心基础部件瓶颈,提升机器人操作灵活性、在线感知能力;2加强服务机器人研究,提升机器人理解人的行为和抽象指令、人机沟通与协调合作能力,建立机器人安全机制;3针对在核辐射、军事战场、自然和人为灾害等危险甚至不可达区域执行任务的需要,开展特种机器人研究,解决在线实时交互、动态未知环境中自主作业等问题,实现机器人与人共处同一环境空间互助作业,为开发国家亟需的现代机器人提供科学理论和关键技术支撑。

摘要：针对执行系统概念设计过程前期阶段的计算机辅助实现是一个难题的现状,将遗传算法引入执行系统概念设计的行为结构分组创新。将行为集合分解为相互矛盾的行为和相容行为,相互矛盾的行为数决定基因串各段规模,相容行为数决定基因串段数,构成行为结构的基因串编码方法。基于行为分组评价规则,定量化形成目标函数并构造适应度函数,通过设定的基因操作,实现行为分组的计算机优化,达到行为结构的变型创新。算例分析表明所提出方法的有效性,有助于实现执行系统的计算机辅助概念设计。