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排序方式： 共有247条查询结果，搜索用时 15 毫秒
1.
车辆轮对踏面缺陷的光电检测方法研究 总被引：1，自引：0，他引：1
铁路车辆轮对踏面的擦伤与剥离是车辆在运行过程中形成的一种常见的不规则表面缺陷,是轮对检修过程中必须检测的一个项目。提出了一种利用光电技术非接触测量此表面缺陷的方法。该方法在轮对旋转条件下,用精密激光位移传感器对踏面进行快速扫描,采集值经处理后被转换为数字图像,再通过图像处理识别是否存在表面缺陷。必要时通过对缺陷部位的往复扫描,更准确识别出擦伤与剥离是否超出段修限度。该方法可有效检测出踏面缺陷,重复性好,可满足车辆段修现场使用要求。 相似文献
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This paper deals with the mechanics involved in a spinning wheel of which the pivot is not fixed as usual but is forced to rotate along the circumference of a circle on the horizontal plane. The usual Euler equations are extended so that, in addition to the three well-known rotations (Euler angles), they also include a fourth one related to the rotation of the motor that induces the forced precession. This study aims at offering a first insight in one of the renowned Laithwaite's experiments. The derived theoretical expressions are accompanied by computer simulation. 相似文献
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Planetary rovers need high mobility on a rough terrain such as sandy soil, because such a terrain often impedes the rover mobility and causes significant wheel slip. Therefore, the accurate estimation of wheel soil interaction characteristics is an important issue. Recent studies related to wheel soil interaction mechanics have revealed that the classical wheel model has not adequately addressed the actual interaction characteristics observed through experiments. This article proposes an in-wheel sensor system equipped with two sensory devices on the wheel surface: force sensors that directly measure the force distribution between the wheel and soil and light sensors that accurately detect the wheel soil surface boundary line. This sensor design enables the accurate measurement of wheel terrain interaction characteristics such as wheel force distribution, wheel–soil contact angles, and wheel sinkage when the powered wheel runs on loose sand. In this article, the development of the in-wheel sensor system is introduced along with its system diagram and sensor modules. The usefulness of the in-wheel sensor system is then experimentally evaluated via a single wheel test bench. The experimental results confirm that explicit differences can be observed between the classical wheel model and practical data measured by the in-wheel sensor system. 相似文献
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This paper presents a design of hillside vehicle power chassis with the balance rocker suspension mechanism. The objective of design is to achieve a variable ground clearance, variable wheel track and self-leveling chassis adapted to the various types of crop grown ridge section and height. The V2-HVPC design consists of the main body, the balance rocker suspension, two driving axles and the steering system. Those assemblies form an H-type chassis structure where both sides of the driving axle and the main body are connected to power transmission. The ground clearance and wheel track have the adjustable function. The balance rocker suspension is a novel mechanism which ensures full-time four-wheel drive in a complex road environment while maintaining the main body level always in the angle bisector of the two driving axle. According to the hillside terrain and agronomic characteristics of various crops, the ground clearance and the wheel track can be adjusted continuously and smoothly by hydraulic system. The topology diagram and power transmission system diagram are all given correspondingly. Moreover simulation analysis and basic experiments have been carried out to verify the mobility and dynamic performance of the V2-HVPC. The results show that the concept of V2-HVPC is approved reasonable and the design and testing methods are feasible and practical. 相似文献
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振动轮式微机械陀螺仪存在两个主要的工作模态 :驱动模态和敏感模态。本文研究了敏感模态反馈控制环节对系统工作性能的影响。提出刚度、阻尼组合反馈的模态控制思想 ,探讨了利用刚度反馈控制敏感模态的固有谐振频率 ,利用阻尼反馈控制系统检测范围的多参量控制方法 ;并对敏感模态中刚度反馈校正环节和阻尼反馈的校正环节进行了详细的分析 ,建立了系统对两个校正环节在增益和相位上的要求。 相似文献
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两类图的(d,1)-全标号 总被引：1，自引：0，他引：1
主要讨论了W_n与C_m的笛卡尔积和均衡完全r-部图K_r(n)的(d,1)-全标号,并得出了(d,1)-全数λ_d~T(W_n□C_m)和λ_d~T(K_(r(n)))的确切值. 相似文献
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给出了轮图W_n、扇图F_n、风车图K_2~t、图D_(m,4)、图D_(m,n)、齿轮图W_n的一般邻点可区别色指标. 相似文献