Overall life cycle comprehensive assessment of pneumatic and electric actuator

Pneumatic actuators and electric actuators have almost been applied to all manufacturing industries. The two kinds of actuators can replace each other in most fields, such as the point to point transmission occasion and some rotating occasions. However, there are very few research results about the advantages and disadvantages of two kinds of actuators under the same working conditions so far. In this paper, a novel comprehensive assessment method, named as overall life cycle comprehensive assessment （OLCCA）, is proposed for comparison and assessment of pneumatic and electric actuators. OLCCA contains mechanical properties evaluation （MPE）, life cycle cost analysis based on users （LCCABOU） and life cycle environmental impact analysis （LCEIA） algorithm in order to solve three difficult problems： mechanical properties assessment, cost analysis and environmental impact assessment about actuators. The mechanical properties evaluation of actuators is a multi-objective optimization problem. The fuzzy data quantification and information entropy methods are combined to establish MPE algorithm of actuators. Two kinds of pneumatic actuators and electric actuators with similar bearing capacity and similar work stroke were taken for example to verify the correctness of MPE algorithm. The case study of MPE algorithm for actuators verified its correctness. LCCABOU for actuators is also set up. Considering cost complex structure of pneumatic actuators, public device cost even method （PDCEM） is firstly presented to solve cost division of public devices such as compressors, aftercooler, receivers, etc. LCCABOU method is also effective and verified by the three groups of pneumatic actuators and electric actuators. Finally, LCEIA model of actuators is established for the environmental impact assessment of actuators. LCEIA data collection method and model establishment procedure for actuators are also put forward. With Simapro 7, LCEIA comparison results of six actuators can be obtained： Fossil fuels are the major environmental factor of pneumatic and electric actuators; Environmental impact of electric actuator is large than one of pneumatic actuator under the similar mechanical properties and working conditions of pneumatic and electric actuators. The results are correct and correspond with the actual mechanical properties of actuators. This paper proposes a comprehensive evaluation method of the actuators, which can solve the critical problem that similar electromechanical products are very difficult to be compared with each other from the angle of performance, cost and environment impact.     

A new diagnostic technique for ball screw actuators

Ball screw actuators are electro-mechanical actuators that translate rotational motion to linear motion with little friction; they are used in precise engineering and particularly in aerospace applications where they replace hydraulic linear actuators. Until now, few diagnostic approaches have been developed with regard to fault detection and characterization of ball screw actuators.     

Towards flexible medical instruments: Review of flexible fluidic actuators

Flexible instruments, i.e. instruments presenting a great number of degrees of freedom and able to perform snake-like movements when avoiding obstacles, can find a lot of applications in the medical field. On the other hand, flexible fluidic actuators, i.e. actuators having a flexible inflatable structure and actuated by fluid, present interesting features regarding medical applications. Therefore, this paper proposes to use these actuators to develop medical flexible instruments.Firstly, the advantages and drawbacks linked to the use of flexible fluidic actuators are listed and a discussion about the miniaturization of fluidic actuators peripherics (such as valves) is led. Next, a literature review of the existing flexible fluidic actuators is established. It can serve as basis to develop flexible instruments based on these actuators.     

Synthesizing multi-axis flexure systems with decoupled actuators

The aim of this paper is to introduce a general systematic approach for synthesizing multi-degree-of-freedom (i.e., multi-axis) flexure-based precision motion systems with decoupled actuators. This approach utilizes the geometric shapes of the Freedom, Actuation, and Constraint Topologies (FACT) synthesis approach to help designers rapidly visualize and compare flexure topologies that could be used to successfully decouple any set of actuators intended to drive any set of desired degrees of freedom (DOFs). The ability to correctly synthesize such decoupled systems is important if their stages are intended to be driven by each of their actuators over large ranges without causing their other actuators to (i) experience harmful jamming forces in the case of displacement-based contact actuators, or (ii) displace from their optimally calibrated positions for the case of force-based non-contact actuators. Additionally, such decoupled flexure systems improve the controllability of their stages by minimizing how much the output of any one of their actuators affects the output of their other actuators. This paper provides the systematic steps of the proposed synthesis approach in the context of various case studies.     

水泥行业电动执行器的选型及发展趋势

实现新型干法水泥生产过程自动化,电动执行器起着十分重要的作用.本文介绍了水泥行业中电动执行器的应用、选型和智能电动执行器的应用和发展趋势.     

面向触觉力反馈的可穿戴柔性执行器研究现状

随着最新一代电子产业在可穿戴性、轻便性、舒适性等方面的需求,近年来基于柔性电子材料的执行器设计制造技术已成为商业消费电子和科研领域关注的热点。柔性执行器由柔性材料加工制作,与刚性执行器相比具有更优的轻薄性、柔韧性和适形性,在可穿戴设备的触觉力反馈中可对皮肤产生多种深浅、节拍和加速度可控的多点作用力,协同产生捏、按、拉等触觉行为,并且整体装置轻巧便捷。分类综述针对触觉力反馈的柔性执行器技术,从主体材料和驱动原理两方面对柔性执行器的工作机制和优缺点进行总结,分析了柔性执行器在虚拟现实、教育培训、医疗辅助等领域的应用情况和潜在价值。对用于实现触觉力反馈的柔性执行器的问题和研究难点进行了总结,并得出设计出安全、舒适、美观、安静等性能优良的柔性执行器是促进未来人机交互的研究突破点。     

浅谈电动执行器的选型应用及发展趋势

介绍了国内电动执行器的应用现状及国际智能电动执行器的发展状况,指出电动执行器结构、原理、选型和应用,并给出相应的日常维护保养建议.     

一种新型并联机构的运动学分析

该机构由动平台、静平台、上折页、下折页和作动器构成,动平台与上折页以球副连接,上下折页、下折页与静平台、作动器与静平台以及作动器与上折页以转动副连接。其中上下折页和作动器组成一组支链,支链内部也形成闭环,且由三组对称的支链构成这种折页式三自由度并联机构。为了获得该并联机构的运动学参数变化和奇异性,运用支链坐标系的方法,对该机构的每一个构件都做了详细的运动学分析,并且获得了该系统的雅克比矩阵和各构件的运动学参数。通过对雅可比矩阵的分析,获得了该机构的奇异空间。     

气动网格软体驱动器弯曲变形预测方法

气动软体驱动器作为软体机器人的关键构成单元,在气压作用下可以实现弯曲运动,但目前缺乏合适的方法来研究驱动器的弯曲变形。针对该问题,在分析气动网格软体驱动器弯曲变形原理的基础上,建立了驱动器单个气囊弯曲角度的数学模型并对其弯曲特性进行了分析,进一步建立了单腔室驱动器和多腔室驱动器的弯曲变形预测模型,通过有限元仿真和实物实验验证了弯曲变形预测模型的有效性。     

悬臂梁振动自适应模糊控制及DSP实现

以粘贴压电自感作动器的悬臂梁为研究对象,推导了悬臂梁振动主动控制的压电元传感方程和作动方程的传递函数,给出了压电自感作动器位置配置优化方法,设计了硬件电路以及软件流程.试验结果表明,利用压电自感作动器和模糊自适应控制器可有效地抑制悬臂梁振动.     

仿生扑翼飞行器扑翼驱动机构的设计探讨

本文在简要介绍扑翼飞行器驱动特点及分类的基础上,就基于MEMS技术和基于连杆机构扑翼驱动的机构设计进行了分析比较,探讨了扑翼驱动机构的实现途径和方法。     

基于Cortex-M3的电动医疗床驱动与控制系统

为解决目前国内电动医疗床功能简单、技术落后等问题,提出了一种多个线性驱动器同步运行、实现电动医疗床复杂位置控制的驱动与控制系统。该控制器以Cortex-M3为核心,与线性驱动器上的双霍尔传感器构成了闭环控制回路,通过模糊PID控制,实现了多个线性驱动器的同步运动控制;采用CASS嵌入式开发平台技术,在专用控制器上实现了对控制逻辑的梯形图编程,提高了开发效率;详细地描述了其系统结构、线性驱动器改进的机械结构和控制器软、硬件的设计。该系统已应用于ICU医疗床,通过对3台立柱式推杆同步运动控制和2台手持式推杆的协同控制,结果表明,该系统可实现医疗机构的各种护理和康复功能。     

Next generation actuators leading breakthroughs

Conventional actuators still play the most important roles in motion control of automated machines. However, for advanced machines and instruments with higher performance, the conventional motors seem to be difficult to satisfy the coming sophisticated demands. So, the development of innovative actuators is recognized as one of the most important subjects of the key technology for next generation. Present state of the technology related to innovative actuators is introduced with some examples developed in a national project for new actuators. Essentials to develop a new actuator and to put it to practical use are also commented.     

具有迟滞和蠕变特性压电作动器的模糊自适应逆控制方法

针对具有迟滞和蠕变特性的压电作动器非线性模型,提出了一种前馈控制和反馈控制相结合的自适应模糊逆控制方案。在前馈控制器中压电作动器的迟滞和蠕变非线性特性的逆模型由自适应模糊逻辑系统近似;在反馈控制器中比例控制器用来调节压电作动器的输出误差。该方法可以实时补偿压电作动器的迟滞和蠕变特性,减少作动器跟踪误差。仿真计算结果表明了该方法的有效性。     

改善电致伸缩陶瓷微位移器性能的研究

对压电陶瓷和电致伸缩陶瓷的逆压电效应和电致伸缩效应进行了详细分析，并通过采用所研制的ＨＲＰＤ系列压电／电致伸缩陶瓷驱动电源对ＷＴＤＳ－Ｉ电致伸缩微位移器进行了实验研究，得出采用电极化强度控制的方法使电致伸缩微位移器的迟滞由原来的１５％减小到１％，蠕变由原来的１０％减小到１％，并实现位移输出的线性化。     

直流电激励下的IPMC弯曲大变形力-电耦合模型

为了描述离子聚合物金属复合材料(ionic polymer metal composites, 简称IPMC)悬臂型驱动器在直流电激励下的非线性大变形行为,采用数字图像相关法(digital image correlation, 简称DIC)获得的IPMC应变梯度与激励电压间的关系,与修正后的IPMC电极分布式电阻电容（resistor-capacitor, 简称RC）电路模型相结合,提出了一种具有解析解的IPMC弯曲大变形力-电耦合模型,并采用Pt电极和Ag电极两种IPMC试样对该模型进行了实验验证。结果表明,该模型能够准确地反映IPMC悬臂型驱动器在直流电激励下的整体弯曲变形现象,且适用于采用沉积法制备电极的IPMC驱动器。     

形状记忆合金双程弯曲驱动器的设计及试验

为解决变体机翼中蒙皮大变形与承载力之间的矛盾,同时满足光顺性及疲劳寿命的要求,提出了一种以形状记忆合金板为驱动元件的双程弯曲驱动器。基于形状记忆效应及材料力学弯曲理论,通过对驱动器变形过程中的力学特性进行分析,推导出双程弯曲驱动器的设计理论,再利用热成形法与反变形训练法制备出驱动器样件并进行了变形性能测试。研究结果表明：依据推导出的理论所设计的形状记忆合金双程弯曲驱动器的变形量与试验结果一致;随着加热温度的升高,驱动器的挠度及输出力逐渐增大,直至达到最大值;随着回复弹簧钢板厚度的增大,驱动器的最大挠度及最大输出力减小,加热变形响应速度减慢,但冷却回复响应速度加快;经过循环激励后,驱动器的变形效果稳定。     

电控喷油器用超磁致伸缩致动器发展现状

电控喷油器用致动器的性能,对喷油器喷油特性以及发动机工作性能具有重大影响。探讨了应用超磁致伸缩材料作为换能元件的超磁致伸缩致动器在电控喷油器中的应用现状。首先,介绍了超磁致伸缩致动器的发展背景;其次,简要介绍了超磁致伸缩材料的作用机理、优良特性以及超磁致伸缩致动器的结构原理;然后,将电控喷油器按照致动器通电工作方式、驱动方式的不同进行分类,系统梳理了超磁致伸缩致动器应用于电控喷油器的研究现状;最后,展望了电控喷油器用致动器的发展方向。     

弹性机构振动主动控制中压电作动器/传感器的优化配置

讨论了高速弹性机构构件上压电作动器和传感器粘贴位置优化配置的方法。基于机构弹性动力学控制方程,对系统模态作动力系数矩阵,作奇异值分解和振动响应观测信号,作小波变换,获得了作动器和传感器不同分布情况下作动力和观测信号的能量表达式,提出了判定作动器／传感器最优配置的可控性指标和可观性指标。最后,对弹性连杆机构进行数值仿真,确定了机构构件上压电作动器和传感器的最优配置。     

金属氢化物温度传感器和执行器

本文分析了金属氢化物温度传感器和执行器的温度敏感原理，介绍了几种金属氢化物温度传感器和执行器，并对其特点进行了简单概括。