研究了一种扩大气动量仪电子柱量程的方法.以典型的差压式气动量仪电子柱为例,研究不同条件下气动量仪电子柱的实际输出特性曲线.通过对比不同特性曲线,提出"虚拟标件"的概念,在保留原有符合精度要求的线性段的基础上改进算法,扩大了测量范围,并进行了实验验证.实验结果表明,在保证精度的前提下,气动量仪电子柱的量程扩大了两倍,证明了方法和算法是可行的.相较于其他方法,该方法不需要升级原有的硬件设施,不增加成本,更易于实现,便与推广.

针对小型空气压缩机多级化带来的各级阀门的差异问题,使用单向阀进行配流,研究单向阀参数对斜盘式空气压缩机排气量和压力脉动的影响规律,并对阀门参数和压缩机转速进行优化设计.首先建立单向阀和斜盘式空气压缩机单个气缸的数学模型,再通过更改转速,进、排气阀弹簧刚度和预紧量,得到了转速、阀门参数对压缩机排气量和压力脉动的影响规律.同时以降低压力脉动和提升排气量为目标,采用粒子群优化算法对多级空压机进行优化,得到每级气缸应匹配的最优转速和阀门参数,再确定整体转速,优化得到转速一致时每级气缸阀门的最优参数.结果表明:进气阀参数对压缩机排气量和压力脉动的影响较排气阀来说更大,增加进气阀弹簧刚度和预紧量会降低压力脉动和排气量,增加排气阀刚度和预紧量会增加压力脉动;此外,优化使得各级气缸的压力脉动分别降低了26.5％、36.1％,排气量分别提升了66.9％、48.9％.

针对空气压缩机重量重、气压低无法较好地搭载在机载武器中的问题,提出了一种新型的高压低重斜盘式压缩机.首先,优化传统单级活塞式结构以满足轻量化要求.其次,通过多级压缩的方式,将气缸分为若干级,相同级并联,相邻级串联,且每级气缸直径逐渐缩小,较单级压缩可提高15倍左右且持续可控.通过Matlab建立模型分析运动过程中压强、速度、加速度随转角的变化曲线.最后,针对多级压缩产生的热量问题,采用分级冷却的方式处理,该方式能有效地降低排气温度、提高工作效率.利用龙格库塔法进行热力特性分析与Ansys仿真,验证冷却管路设计.最终实现高气压、轻量化与高效并存的压缩机.

为了探索纳秒脉冲激光在单个微观形貌内的路径规划问题,借助COMSOL Multiphysics有限元仿真分析软件,对脉冲激光加工微凹坑时的温度变化和烧蚀去除材料进行了模拟预估.建立了灰铸铁缸套经高能量激光照射后的温度场和变形场模型,在多物理场耦合作用下,探索单点凹坑精度和效率受激光作用时间、功率等因素的影响,建立预估数据模型,最终仿真试验结果显示:凹坑半径r2∝ ln(t),深度与时间呈线性关系,体积随时间呈二次分布.基于此仿真数据模型探索多点打击规划原则,寻找最优重叠率,并通过试验证实其可行性.

针对目前电动助力转向器在中型清扫车上的应用现状,为了解决电机尺寸过大、应用困难的问题,提出了新型的变传动比传动的设计方案.以某款车型的电动助力转向系统为例,研究了该车所用转向器传动方案及其电机输出力矩变化情况,建立了该转向系统数学模型;结合清扫车使用工况,确定了齿轮齿条变传动比设计参数,进行了相关计算、对比分析,验证了该方案的改进效果.采用新的设计方案可直接缩小助力电机的输出力矩变化范围,降低选取的电机功率值,达到了减小电机尺寸,扩大电动助力转向系统适用范围和节约能源的目的.

针对齿轮测量数据中存在异常值的问题,分别对异常值的4种常用准则进行了对比分析;设计了异常值剔除系统,结合齿轮测量系统所测得的齿轮数据,选用相应的判定准则,对齿轮测量数据进行快速高效的异常值剔除处理.通过实验分析,给出了齿轮测量数据预处理需要遵循的原则.研究结果表明,当对齿轮测量数据进行粗大误差剔除时,需要结合实际情况对4种准则综合运用,以达到所得数据的科学性和合理性,对齿轮误差的后续处理做出科学的预处理.

以一种气动发射装置为背景,介绍了装置的组成、结构、工作原理和发射过程.通过对其物理模型进行简化,在ANSYS Autodyn软件中建立简化模型,并引入了压缩空气有效能,对发射过程进行数值仿真,得到了发射物的加速度和速度随时间变化的曲线,与现场试验采集的速度数据的对比分析,验证了有效能的引入具有一定可信度;也表明了该发射装置的可行性,且结构简单,布局紧凑;另外通过ANSYS Autodyn对发射装置的仿真研究,可以为该型气动式发射装置的设计、优化以及发射试验等工作提供依据.

目前,市面上多进一出的混色3D打印设备存在混色不均、 色块交界域明显等问题.依据高熔融态聚物混合原理,提出一种利用耗材挤入混合腔体积反推混合腔尺寸的方法,并从结构、 压力及速度分布等流场特性对混合腔结构进行分析.分析结果表明,耗材射入混合腔角度及喉管排列形式对混合效果有较大影响.试验结果表明:该方法不仅能够实现不同基色熔融态耗材均匀混合问题,而且能够提高混合效率、 缩短混合时间,为混色3D打印提供一种可行的方法.

为了研究弹性元件在仿人机器人腿部弹性驱动机构中的具体功能,并选择合适刚度的弹性元件,以典型的弹性驱动器为基础,建立了弹性驱动器的位置源驱动模型以及仿人机器人小腿弹性驱动机构模型.对驱动机构重要参数进行优化,确定最优参数值,在给定转角范围内,通过仿真计算分别得到转角和驱动力与驱动位移关系图.对比不同弹簧刚度下的关系曲线,利用MATLAB函数确定最优刚度值,得出在合适的弹簧刚度下,弹性元件具有增强机器人小腿驱动稳定性和精确性的功能的结论.

为提高医用硅橡胶喉罩生产效率,降低成本,促进其工业自动化生产的发展,利用室温硅橡胶粘接剂(RTV)固化反应原理,开发出硅橡胶喉罩的快速粘接工艺,并整合喉罩的生产流程和开发配套的设备,实现了医用硅橡胶喉罩流水线生产模式,淘汰了作坊式生产模式,使得生产效率大幅提高.

BACKGROUND: Three-dimensional magnetic field positioning and three-dimensional electric field positioning are two main technologies used in heart ablation, but their required equipments are very expensive. OBJECTIVE: To develop a new method of ablation catheter positioning by combining ultrasonic probe with ablation catheter. METHODS: Three-dimensional data of human heart were obtained from the anatomical data set of the body, and then a three-dimensional vector model of the endocardial surface was established. The basic parameters and scanning strategy of ultrasonic probe were designed and calculated, to compile a corresponding simulation software. Based on the three-dimensional endocardial vector model, the detection data of the ultrasonic probe were obtained by simulation calculation and processed. Then, the target surface characteristics were reconstructed, matching with the surface features of the proposed vector model. The position of the probe was finally determined. RESULTS AND CONCLUSION: The three-dimensional model of the endocardium was established based on the anatomical data set, and the ultrasonic surface detection data were obtained by the simulated ultrasonic irradiation. The reconstructed surface model with high accuracy exhibited a desired match with the target area in the three-dimensional model of endocardium. The error of the probe position and its theoretical position fulfilled the requirement of positioning accuracy. In conclusion, the use of ultrasonic imaging technology can accurately position the catheter probe in the heart during heart ablation, providing an accurate and reliable navigation for the implementation of heart ablation.

Objective To extract and classify the respiratory sound characteristics by studying the internal relationship between respiratory sound signals and respiratory diseases and provide technical preparations for developing a portable household breathing sound remote monitoring mobile device. Methods After the pretreatment analysis of the collected respiratory sounds, we extracted the characteristic values of short-time energy and short-time zero crossing rate from the processed respiratory sound original data. Results The characteristic differences were displayed by the energy changes of different time quantum respiratory signals, and the results indicated that the high-and low-frequency abnormal signals of respiratory sounds have trivial influence on the feature extraction method. Conclusion The proposed method can be used to extract characteristic values simply and effectively, not only simplifying the characteristics recognition and data processing, but also obtaining the extracted feature parameters which meet the basic characteristics, including otherness, uniformity and correlation. The study provides a theoretical basis and actual data support for establishing the input of neural network.

The Programmable System-on-Chip (PSoC) which is produced by Cypress semiconductor company can be regarded as 8 bit micro controller.It can realize multi-configuration of analog devices, digital devices and analog digital devices.The paper studied differential inductance sensor micro controller design scheme based on PSoC.It can connect micro controller with differential inductance sensor, filter sensor output signal and realize the AD conversion the of the output results.Compared with coordination design scheme which needs multiple chip and external hardware ,this scheme simplifies the production and measurement of AC signal, can maintain a high system performance at the same time, and reduces the plate space, power consumption.

A new multistage swash plate piston gas pump is proposed .According to the structural characteristics of the two-side swash plate gas pump and the law of relative motion of its pistons , multistage compression could be achieved by dividing the cylinders into several levels and connecting the cylinders at the same level in parallel and the cylinders at the adjacent level in series with check valve rectifying in the front and back cylinder cover .The structural characteristics and working principles of the gas pump were elabora-ted.The kinematic characteristics of the gas pump were analyzed and calculated .Mathematical model of gas compression and expansion thermal process for the gas pump was established and the fourth order Runge-Kutta numerical method was used to solve it .The thermo-dynamic characteristics of the gas pressure and temperature in the work process of the gas pump were analyzed .Furthermore, the ad-vantages of the multistage compression with respect to the single-stage compression are comparatively analyzed from two aspects of sav-ing the indicated work of the compressed gas and reducing exhaust temperature .

Mathematical model of gas compression and expansion process for swash plate air compressor with gas leakage and unsteady heat transfer is established based on the motion characteristics of the swash plate air compressor and the variable mass thermodynamic theory.The fourth order Runge-Kutta numerical method is used to solve the mathematical model.The variation curve of the gas mass,pressure and temperature along with the main shaft angle in the work process of the swash plate air com-pressor were obtained and the effects of the gas leakage and unsteady heat transfer are discussed respectively.The results provide a reference for the design and application of the swash plate air compressor.

建立了一种通用气动式制动能量回收系统的数学模型.针对不同汽车制动的初始平均速度及高压储气罐预冲压力、容积等关键参数,在MATLAB中进行了仿真计算,通过分析系统工作过程中汽车的车速变化及系统高压储气罐的气压变化,研究系统的可行性及其能量回收效率.结果表明:系统的制动能回收效率与高压储气罐的预充压力成正比,与高压储气罐的容积成反比,合理地确定高压储气罐预充压力和容积,系统回收效率可达20％;当汽车速度较低时,车辆仅依靠气动式制动系统,可满足汽车对制动距离的标准规定.

在目前常规游梁式抽油机增加自适应平衡重装置,通过优化设计可使改造后减速器均方根净扭矩有所下降,一定程度改善抽油机平衡状况,对于传统抽油机在节能降耗等方面具有参考和借鉴意义.

通过对非圆齿轮—曲柄摇杆机构数学模型的构建,分析了该机构的动力学和运动学特性,据此得出非圆齿轮—曲柄摇杆机构的扭矩因数变化及传动比特性。并以改善抽油机运行过程中的负扭矩为目标,设计了应用于现有游梁式抽油机的非圆齿轮副的研究方案。结果表明,运用非圆齿轮的结构和传动的特点,重新设计游梁式抽油机的减速机构,用非圆齿廓部分替代一级圆柱齿轮进行传动,既保证了游梁式抽油机工作行程的稳定,又能够有效的改善游梁式抽油机在运行过程中出现的不平稳和负扭矩状况。

In order to find out the most suitable dynamic rolling mode for the winding equipment with a proper precision,a dynamic weighing system is presented based on tension measurement.Furthermore,combining with theoretical mechanics and dynamics,weight signal feature and error model of three different control schemes-constant tension (constant linear velocity),constant rotating speed and taper tension are analyzed comparatively.Experiment results of constant rotating speed control scheme show that the system is stable and efficient;moreover,weighing error can be reduced within 0.5％.

本文以航空冲压件回弹引起的尺寸误差为控制目标,建立模具回弹补偿修正算法.本算法依据模具和冲压件的激光三坐标测量数据,修正模具型面数据.在此基础上,本文对冲压件回弹量影响因素作了分析,并提出了一种基于改进的变压力模型用于回弹控制.