基于接触性检测的IC热阻测试新方法

热阻对于半导体器件,尤其是大功率器件的可靠性至关重要。基于集成电路接触性检测原理和二极管的温度特性,对54HC02和74HC02集成电路端口的保护二极管温度特性进行了测试实验,通过曲线拟合得到了其恒定正向电流条件下正向压降VF与温度T的线性函数关系式。测得集成电路在瞬态工作功耗下的正向压降,通过该函数关系式可得到对应的芯片温度,在已知功耗和环境温度的条件下可以计算出电路对环境的热阻θJA。使用该方法测试54HC02和74HC02分别为135℃/W和115℃/W,与手册给出的参考值122℃/W和112℃/W比较接近。

非接触性动态位移测试方法的研发及应用验证

基于Hough变换圆检测原理研发了非接触性动态位移测试方法,采用振动台进行了应用验证.结果表明,Hough变换具有良好的圆检测效果.图像计算效率与角度、半径的检测步长的选取相关;选取较大半径检测步长时,图像处理速度将大幅提高;选取较大角度检测步长时,图像处理速度提高并不显著.通过不同试验验证了自行研发的非接触性位移测试方法在不同频率正弦波输入、图像中不同半径标靶圆及相机-标靶不同物像空间距离特性条件下均具有良好的识别效果.工程实用角度,非接触性位移测试方法可以同时捕捉多个测点的位移及有效解决测试量程受限的问题,并可避免由于接触对被测体产生的干扰.

基于最优圆拟合原理的非接触性动态位移测试方法及可视化软件的研发

研发了基于最优圆拟合原理的非接触性动态位移测试方法及面向对象的可视化软件,采用小型振动台试验进行了应用验证。结果表明:研发的非接触性动态位移测试方法具有良好的标靶圆检测效果,可以完整捕捉标靶点动态位移,位移测试达到亚像素精度;对于不同频率的正弦波输入,非接触性动态位移测试方法识别给出的台面水平位移时程与应变式位移计测试给出的台面水平位移时程的相似度均高于0.98。该技术有效解决了传感器不便布设环境的位移测试、常规物理传感器测试方法的测试点位与位移量程受限的问题,并可避免由于接触对被测体产生的干扰。

社会接触测试对导盲犬培训成功率的预测效果评价

目的 建立社会接触测试,并探究其预测导盲犬培训成功率的有效性.方法 通过对犬心理评估（DMA）测试方法进行改良,建立了犬社会接触测试方法及相应的详细评分标准.对中国导盲犬大连培训基地提供的17只培训成功的导盲犬和17只未培训成功的淘汰犬进行社会接触测试,考查和评估社会接触测试中问候、合作及触摸这3个行为变量对导盲犬培训成功率预测的有效性.结果 问候变量,导盲犬与淘汰犬的得分没有显著差异（导盲犬∶（x） =3.29,淘汰犬∶（x）=3.18,P=0.716）;而合作和触摸变量,导盲犬的得分显著高于淘汰犬（合作∶导盲犬∶（x）=4.29,淘汰犬∶（x）=3.41,P=0.005;触摸∶导盲犬∶（x）=3.59,淘汰犬∶（x）=3.00,P=0.049）.社会接触测试中,犬的品种和性别对各行为变量的得分没有显著影响（P＞0.05）.结论 成功建立了社会接触测试的方法及评分标准,其中合作和触摸可作为有效预测导盲犬成功率的行为变量.

基于计算机视觉的位移测试方法研究与实现

针对Hough变换、最优圆拟合两种圆检测算法进行了圆检测效果、算法应用范围及计算效率的对比分析;研发了基于圆检测算法的非接触性动态位移测试方法并应用于大型振动台实验。结果表明:Hough变换圆检测及最优圆拟合圆检测均具有较好的圆参数检测效果。Hough变换圆检测方法更适用于测试背景简单且需单次识别多个标靶圆的工况;最优圆拟合圆检测方法更适用于测试背景复杂的工况。应用非接触性位移测试方法于大型振动台试验中,测试了模型地基土的位移反应。应用基于机器视觉技术的位移测试方法可以有效解决复杂工况下的位移测试问题。

Optimization and experimental research on a new-type short cylindrical cup-shaped harmonic reducer

In order to obtain a new-type short cylindrical cup-shaped flexspline that can be applied to space mechanisms,the APDL language of ANSYS software was employed to develop a parameterized equivalent contact model between a flexspline and a wave generator. The validity of the parameterized equivalent contact model was verified by comparing the results of the analytic value of the contact model and the value calculated by the theoretical formula. The curvilinear trend of stress was obtained by changing the structural parameter of the flexspline. Based on the curvilinear trend of stress,multi-objective optimizations of key structural parameters were achieved. Flexspline,wave generator,and circular spline of a new 32-type short cylindrical cup-shaped harmonic reducer were designed and manufactured. A performance test bench to carry out tests on the harmonic reducer was designed. Contrast experiments were implemented to determine the efficiency of the new 32-type short cylindrical cup-shaped harmonic reducer and the conventional 32-type harmonic reducer under different conditions. The experimental results reveal that there is approximately equality in terms of efficiency between the new 32-type short cylindrical cup-shaped harmonic reducer and the conventional 32-type harmonic reducer. The volume of the flexspline of the new 32-type short cylindrical cup-shaped harmonic reducer is reduced by approximately 30% through multi-objective optimization. When the new 32-type short cylindrical cup-shaped harmonic reducer is used on the wheel of a rover prototype,the mass of the wheel hub is decreased by 0.42 kg. Test analysis of wheel motion verifies that the new 32-type short cylindrical cup-shaped harmonic reducer can meet the requirements regarding bearing capacity and efficiency.

Analysis on performance and test of a new type of ultra-high pressure pipe joint

Analysis as well as application of ultra-high pressure hydraulic system and elements has become a trend. The structure and operation principle of a new type of ultra-high pressure pipe joint is introduced. The structure of the new type of ultra-high pressure pipe joint is simple and is easy to be produced. The finite element model on two working conditions( preload condition with 30 N·m torque and static-loading condition with 70 MPa pressure) is built and computed. The width of contact area,the equivalent stress status,as well as the contact pressure status are plotted and analyzed. According to the national standard,test on air-tightness,blasting,and cyclic endurance is conducted and the results show that the new type of ultra-high pressure pipe joint has the sealability for ultra-high pressure up to 70 MPa,and the DN6 ultra-high pressure pipe joint can provide effective seal under70 MPa fluid pressure. The research can provide a thinking and method on designing ultra-high pressure pipe joint and push forward the development of ultra-high pressure hydraulic system.