排序方式: 共有154条查询结果,搜索用时 15 毫秒
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沉浸式虚拟维修环境下,物体间发生穿越的碰撞问题可以分为3类:1点接触,2点接触和3点及3点以上接触。采用改变碰撞物体的运动方向和距离的方式来避免物体间穿越现象的发生。并以实例的方式对其有效性进行了验证。 相似文献
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机动目标建模及机动检测算法 总被引:1,自引:0,他引:1
为解决机动目标跟踪问题,建立了非机动(匀速直线运动)和机动目标当前统计两种动态模型,并对机动目标当前统计模型的输入控制的估计进行了适当改进.同时对非机动模型的观测残差和机动模型的输入估计进行检验,以便准确检测目标机动. 相似文献
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零燃料大角度姿态机动技术是新近应用在国际空间站的新概念姿态控制技术。构造了以控制力矩陀螺为执行机构的空间站姿态控制动力学模型,在此基础上,建立了空间站本体与控制力矩陀螺之间的角动量守恒关系。针对各类大角度姿态机动任务,通过分析空间站惯量参数与控制力矩陀螺性能参数之间的解析关系,得到了零燃料大角度姿态机动路径的存在性条件。通过规划算例验证了存在性分析的正确性。所提出的零燃料大角度姿态机动存在性条件,为姿态机动路径的存在性判断提供了便捷可行的方法,为零燃料大角度姿态机动技术未来在我国空间站实施的可行性论证提供重要的理论依据。 相似文献
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为探讨反舰导弹非平面机动对舰炮武器系统反导能力的影响,仿真计算了反导舰炮对末端作摆式机动和螺旋机动目标的命中概率,分别给出了不同机动周期、不同机动幅度、不同舰炮射速时的命中概率图线。结果表明,非平面机动无需大幅度机动就能很好抑制反导舰炮的反导能力;且螺旋机动突防效果更好;而舰炮射速对舰炮武器系统的反导能力至关重要。 相似文献
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基于LS-DYNA的动力学分析通用有限元程序,对爆炸成型弹丸形成和侵彻靶板过程进行了数值仿真。建立了数值仿真模型,利用数值模拟技术实现了弹丸的形成以及不同药型罩结构对爆炸成型弹丸形成的影响,实现了侵彻过程中弹丸的变形与靶板的破坏状况可视化,同时对仿真结果进行了分析。通过对爆炸成型弹丸侵彻靶板的数值仿真,为开展爆炸成型弹丸毁伤机理研究奠定了良好的基础。 相似文献
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对运动视觉平台点目标定位问题进行了研究,介绍了基于视觉共线方程的目标定位方法,分析了共线方程关于视线约束的实质。在观测视线相关坐标系推导了视线方向角矢量对目标定位误差的影响规律,分析了多观测对定位误差的影响,并基于最小化目标定位误差推导了视觉平台的最优运动轨迹,利用简单明了的分析方法得到了与已有文献优化Fisher信息矩阵方法一致的结论。利用仿真和试验对定位误差和最优轨迹进行了验证,证实了定位误差理论分析和最优运动轨迹设计的正确性。 相似文献
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《防务技术》2019,15(6):829-836
The depth of penetration (DOP) method is a well-known ballistic test method for characterisation and ranking of ceramic armour materials. The ceramic tile is bonded to a backing material of semi-infinite thickness, and the penetration depth of the projectile gives a measure of the performance of the ceramic. There is, however, an inherent variability in the results from this test method. In this work, the accuracy and the variability of the DOP method has been investigated in a round robin exercise. Six ballistic test centres took part in the exercise. A test protocol was developed, in which the threat type (projectile and impact conditions) and a procedure on how to prepare the targets were specified. The targets consisted of alumina tiles of two different thicknesses that were bonded to polycarbonate backing cubes. Two different 7.62 mm armour piercing projectiles were employed; one with a hard steel core and one with a tungsten carbide core. The projectiles and the other materials all came from single material batches in order to avoid batch-to-batch variations in material properties. These materials were distributed between the ballistic test centres. The test results of the different ballistic test facilities were collected and compared. There was not a lot of variation between the average DOP values obtained at each laboratory, but the variation in penetration depth between shots was high. The consequence of this variation may be less confidence in the test results, and a statistical method was used to evaluate the required number of tests that are sufficient to obtain an average result with high confidence. In most cases, the required number of tests is much higher than what is practically feasible. This work was conducted as part of the European Defence Agency-project CERAMBALL. 相似文献
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运用冲击波理论,对横向效应增强型弹丸(Penetration with Enhanced Lateral Efficiency,PELE)侵穿金属靶板的机理进行了分析,将PELE侵彻过程中能量损失分为外壳和内芯撞击靶板区域环形塞块获得的能量,冲击波影响范围内外壳和内芯增加的内能,外壳前端外沿和内沿对靶板冲塞剪切耗能等,给出了确定这些能量的计算方法;并依据能量守恒原理,给出了PELE正撞金属薄靶板靶后剩余速度的近似计算公式。公式计算结果与多种条件下实验结果均吻合较好。分析计算所得各能量损失结果表明,弹体内芯材料的变化对弹体侵彻能力的影响较小;侵彻中靶板塞块获得的能量在弹体侵彻动能损失中比重最大;外壳前端内沿对靶板的剪切能耗对弹体动能损失的影响可以忽略。 相似文献