搜索结果: 91-105 共查到“知识库 机械电子工程”相关记录141条 . 查询时间(3.106 秒)
Design and Analysis of a Mechanical Device to Harvest Energy From Human Footstep Motion
energy harvesting dual-oscillating mechanism human motion
2011/5/18
Portable electronics is usually powered by battery, which is not sustainable not only to the longtime outdoor use but also to our living environment.
Ignition Pattern Analysis for Automotive Engine Trouble Diagnosis using Wavelet Packet Transform and Support Vector Machines
automotive engine ignition pattern diagnosis pattern classification
2011/5/12
Engine spark ignition is an important source for diagnosis of engine faults. Based on the waveform of the ignition pattern, a mechanic can guess what may be the potential malfunctioning parts of an en...
Microstructure and Mechanical Behavior of In Situ Primary Si/Mg2Si Locally Reinforced Aluminum Matrix Composites Piston by Centrifugal Cast
Piston Centrifugal casting In situ composite Primary Si Mg2Si
2011/5/12
Al-Si pistons are frequently damaged by burning piston top surface due to elevated combustion temperature, and, by rubbing the first ring groove against the engine cylinder liner. To prevent from thes...
基于离散傅里叶变换计算介质损耗因数的二周期修正法
离散傅里叶变换 介质损耗因数 二周期修正法
2011/5/10
提出一种基于离散傅里叶变换的二周期修正法, 利用该方法可计算电力系统的介质损耗因数. 通过将电网信号两个周期的采样修正为一个周期, 可减小由频率偏移导致的频谱泄露和截断误差. 误差分析表明, 该算法与传统方法(加窗法)的精度具有相同的数量级, 但其运算时间比传统方法运算时间减小3倍以上.
液压挖掘臂伺服系统是复杂非线性系统，针对线性模型难以准确反映系统动态的特性，采用包含静态非线性模块和动态线性模块的Hammerstein模型来描述该系统。Hammerstein模型中的线性模块采用离散自回归模型(ARX)，非线性模块则采用分段多项式基函数。利用多频率正弦激励与角度输出信号，采用带遗忘因子的递推最小二乘法实现线性与非线性模块参数的解耦辨识。通过对比实验分析辨识所得Hammerstei...
研究微机械陀螺仪的零位误差对提高惯性导航精度具有重要意义。论文采用Allan方差分析法对MEMS陀螺仪的零位误差做了综合评定，提出了一种动态的零值偏移误差补偿算法来滤除陀螺仪的零值偏移误差；论文还对启发式漂移消减法（HDR，heuristic drift reduction）做了改进，有效的提高了原算法的补偿精度。最后，再次采用Allan方差分析法对补偿后的零位误差进行评定，并以Voyager-I...
Structural Surface Crack Monitoring Method Based on Electrical Potential Technique and Modern Surface Technology
crack monitoring electrical potential technique surface technology
2011/3/18
Crack monitoring plays a great role in modern structural health monitoring, however, most of the conventional crack inspections have disadvantages in terms of the accuracy, expense, reliability, durab...
Control System Design for an Unmanned Helicopter to Track a Ground Target
unmanned helicopter trajectory plan target tracking
2011/3/18
Due to potential wide applications, the problem of utilizing an unmanned helicopter to track a ground target has become one of the most active research directions in related areas. However, in most ca...
Structural Damage Detection Method Based on Decomposition of the Operating Deflection Shapes
damage detection decomposition operating deflection shape (ODS)
2011/3/18
Full-field measurement techniques such as the scanning laser Doppler vibrometer (LDV) and the electronic speckle pattern interferometry systems can provide a dense and accurate vibration measurement o...
基于不确定能力参数的制造资源区间优化检索方法
制造资源 区间转化 信息模型 优化检索
2011/2/28
针对网络环境中制造资源和任务信息的不确定性,构建了资源和任务的信息模型,并对其能力参数进行了形式化描述。针对不确定性能力参数,探讨了制造资源参数区间的转化规则。利用区间距离的概念,提出一种在网络环境中进行制造资源优化检索的新方法,并通过实例验证了该方法的有效性。
Ultrasonic Nondestructive Signals Processing Based on Matching Pursuit with Gabor Dictionary
ultrasonic signal processing sparse representation matching pursuit
2011/2/24
The success of ultrasonic nondestructive testing technology depends not only on the generation and measurement of the desired waveform, but also on the signal processing of the measured waves.
Flow Field Characteristics for Parachute-projectile System
parachute projectile flow field computational fluid dynamics (CFD)
2011/2/23
In the current research for parachute flow field nowadays, the size of parachutes in previous research are so large compared with their carriers that the effects of the carriers wake flow to parachute...
针对机械式按摩椅缓解肌肉疲劳的绩效,提出了基于表面肌电（sEMG）信号的人机评价模型。实验要求两名被试者在执行静力性标准俯卧撑（SPU）动作之间,分别采用静坐与按摩两种方式恢复肌肉疲劳,并在SPU过程中采集竖脊肌的sEMG信号。根据模型的评价指标对实验数据进行了比较与分析,结果表明,SPU后采用拍打按摩恢复对竖脊肌疲劳缓解的效果好于静坐恢复的效果,从而验证了模型在按摩椅人机评价上的可行性。
带长管道的阀控马达无磁转台控制策略研究
无磁转台 长管道 控制策略 速率精度
2011/2/15
针对带长管道的阀控马达系统用常规PID策略控制效果不理想的缺点,提出了一种新的PIDD控制策略对系统进行控制。以考虑管道效应的系统数学模型为基础,引入对凸轮转子叶片马达所受扰动力矩的分析,并结合时滞系统的特点,导出了PIDD控制策略。实验和仿真结果基本一致,表明该控制策略能显著提高系统的速率精度并有效地减少抖动,达到很好的控制效果。
Receptance Coupling for Tool Point Dynamics Prediction on Machine Tools
receptance coupling dynamics endmill chatter
2011/1/24
Chatter has been a primary obstacle to the successful implementation of high speed machining. The frequency response function(FRF) of the tool point is crucial for identification of chatter free cutti...