三线摆实验仪角度控制装置的设计与制作

用三线摆测刚体转动惯量的实验条件是转动圆盘角度要小于 5°,在实验中因仪器没有配置角度的控制装置 ,因此无法准确控制角度 ,不能满足实验条件 ,造成实验结果误差增大。装上角度控制装置后 ,转动角度可精确控制小于 5°,保证了实验条件和实验结果的误差减小。     

扭摆法测转动惯量实验装置的研究

传统的扭摆法测转动惯量多使用单线摆、三线摆等,针对传统的扭摆法测转动惯量装置的一些缺陷,比如由于产生摆动、计时方法不科学使计时结果不准确、装置不能保持在水平面上转动等造成的测量误差较大的问题,研究制造了一种新的实验装置。这套装置用涡卷弹簧提供扭摆的动力,用光电对管配合单片机进行精确计时,并且采用了变面接触为线接触等多种减小摩擦的设计来提高测量精度,使误差大大减小了。整套装置具有测量结果精确、操作简单、体积小、能测量不规则的及难以直立的物体的转动惯量、能很好地验证平行轴定理等优点。     

利用智能手机旋转传感器测量转动惯量

在用三线摆测量转动惯量的实验中,利用智能手机旋转传感器测量出刚体在转动时的旋转角度与时间的图像,然后计算出摆动的周期,进而测量出刚体的转动惯量。并将手机测量结果与传统实验结果进行比较,验证其可行性。     

滚动法转动惯量测量仪

转动惯量是刚体的重要属性,也是大学物理刚体部分的重要内容。目前,大学物理实验主要采用扭摆法与三线摆法测量物理的转动惯量。此两种方法所采用原理与大学物理课中的知识关系性较少。本实验项目采用新的方法——滚动法测量物体的转动惯量。此方法有效的将刚体的平动、转动、势能与动能的转换相结合利用能量守恒,计算出刚体的转动惯量,其相对误差可以控制在5%以内,且其运行原理简单易于理解。该装置具有操作简单、测量速度方便快捷的优点,具有一定的推广价值,同时为转动惯量的测量方法提供技术支持。     

用数字式测定仪测定物体的扭转周期

介绍了用数字式测定仪代替停表（秒表）,测定系统的转动周期的方法。实验表明,使用测定仪不仅能提高实验效率而且能减小误差。     

刚体转动惯量测量实验仪的改进

对F D I M I I型新型刚体转动惯量测量仪进行了改进, 从仪器的摆角控制、 周期自动测量两个方面进 行改进, 用改进后的仪器对圆盘和圆环的转动惯量进行测量, 从实验数据分析发现, 圆盘和圆环的理论值和实验值 的百分误差小于5%, 可以有效地减小实验误差     

双悬扭摆测量转动惯量及平行轴定理的实验研究

转动惯量是描述刚体转动惯性量度的重要物理量, 它具有重要的物理意义. 本文利用一种双悬扭摆的 实验装置来对物体的转动惯量进行实验研究以及对平行轴定理进行实验验证     

基于PASCO转动运动传感器测量刚体转动惯量

PASCO转动运动传感器可以精准地测量并实时地记录物体转动时的角速度。在落体法测量刚体转动惯量的实验中，为了提高实验的精度，将PASCO转动运动传感器与刚体转动惯量实验仪相结合，用PASCO转动运动传感器直接测量角速度并计算角加速度。改进后的仪器简化了实验步骤，提高了实验精度。对圆盘、圆环和圆柱试样的转动惯量进行测量，三组实验的相对误差分别为0.2%、0.7%和0.3%,实验结果准确。通过实验结果可得，改进后的实验仪器操作简单且测量精度很高。     

关于刚体转动惯量测定的计时方法研究

本文给出了在刚体转动惯量的测定中测定时间的计时装置，减小了计量时间所带来的误差。     

微型无刷直流电机位置系统的过程控制

为了实现机械相控阵列天线的波束扫描,采用微型无刷直流电机驱动螺旋天线单元转动来到达预定的辐射相位。设计了一种新型微型无刷直流电机位置控制系统,构建了比例滑模面-超螺旋二阶滑模控制器用于速度控制,利用结合速度剖面策略的PID控制算法实现了转动位置的中间过程控制。建立了基于Simulink的系统仿真模型,验证了方案的可行性,并构建了FPGA硬件实验平台。仿真和实验结果均表明,微型无刷直流电机驱动天线单元精确按照预设的速度剖面曲线运行,在50 ms控制周期内转动角度达到180°,中间控制过程的位置跟踪误差和平衡位置处的残余震荡误差均小于±3°。     

Optical measurements of angle and axis of rotation

A carousel interferometer is designed to find the unknown angle and axis of rotation simultaneously. A set consisting of a compensator glass plate and a right-angle prism is placed in each of the two arms of the interferometer while located at the same rotational stage. When rotation takes place individual and relative optical path differences are generated in the beams that contribute toward finding out the angle and axis of rotation. Computer simulation shows that error remains less than a nanometer for a 1 m length of unknown radius and rotation range of +/-15 degrees .     

测量不同质量圆盘下圆盘的转动惯量误差的研究

实验由三线摆法测量物体的转动惯量,现在采用累积放大法测量周期,用平均值计算周期,分析圆盘转动惯量测量值及理论值的百分差与下圆盘质量之间的关系,从而来研究一定高度不同质量圆盘下圆盘转动惯量产生的误差影响。最后得出实验结果,下圆盘质量越小,误差越小,当下圆盘质量小于0.085kg时,误差突然增大。     

Derivation of microscopic uni-axial unified adiabatic Bohr–Mottelson rotational model

For a rotational motion about a single axis, we derive a microscopic, quantum version of the phenomenological Bohr–Mottelson unified adiabatic rotational model without using redundant coordinates, imposing constraints on the intrinsic state or the particle coordinates, or assuming explicitly a deformed intrinsic state. The model Schrödinger equation is derived from the direct action of the multi-particle Hamiltonian operator on the rotational-model wavefunction. We show that the Coriolis-coupling terms in the derived Schrödinger equation vanish exactly only for a choice of the Euler angle that is consistent with the rotational model requirement that the intrinsic wavefunction be invariant under rotation. For this angle, which also satisfies the conjugate commutation relation, the kinematic moment-of-inertia tensor, collective-rotation velocity field, and flow vorticity have the rigid-flow characteristics. Pairing interaction and fluctuations in the rigid-flow moment of inertia are shown to reduce the rigid-flow value of the kinematic moment of inertia in closer agreement with the experimental value. The derivation shows that a multi-fermion system with unpaired or paired (quasi) particles rotates nearly rigidly and a single-particle system rotates irrotationally if the intrinsic system is rotationally invariant, regardless of the value of the moment of inertia and the nature of the rotationally-invariant momentum-independent interaction.     

扭摆法测转动惯量的系统误差与实验改进

本文研究分析扭摆法测量转动惯量实验的系统误差来源,在此基础上对实验方法、装置提出改进,改进后实验结果与理论值的百分差可降低一至二个数量级．     

Coupling of the rotational motion with the axial vibrations of multipolarity 2 and 4

The unadiabatic effects related to the coupling between the rotational and vibrational degrees of freedom are investigated. The collective Hamiltonian is constructed using the concepts of the Bohr theory and includes the degrees of freedom corresponding to the axial quadrupole and hexadecapole vibrations. The coupling of the nuclear vibrations with the rotational motion is so strong that one has to multiply the inertial parameters and the moment of inertia by the factor 1.7 in order to get the experimental energies spacing in the ground state bands. The dynamical effects to the electric quadrupole and hexadecapole moments are considered. The parameter of unadiabaticityα calculated within the model agrees well with the experimental data.     

激光束散角复合控制技术

为了降低部分相干光光学系统设计的复杂度及成本,增加部分相干光应用的便捷性,提出了一种液晶空间光调制器的激光相干度及束散角复合控制方法。首先介绍了对激光光束进行相干度和束散角复合控制的基本理论和方法;然后分别设置了相干度和束散角检测实验,检测了本方法所调制激光光束的相干度和束散角的准确性。实验结果表明,采用液晶空间光调制器生成相干度为0.9 mm、束散角为7.5 mrad,以及相干度为1.5 mm、束散角为3.8 mrad的部分相干光束,其相干度与理论值相比误差在5%以内,其相干度均方根误差分别为0.027386和0.031314,峰谷值分别为0.084658和0.089103;其束散角与理论值相比误差在5%以内,其束散角均方根误差分别为0.022478和0.023186,峰谷值分别为0.081201和0.092130。可见,该方法可以实现高精度的相干度及束散角复合控制。     

视轴角控制误差对航天相机成像质量的影响分析

为了降低飞行器倾斜成像工作过程中视轴角误差对TDICCD空间相机成像质量的影响,提出满足相机成像质量的视轴角范围及控制误差的要求。根据空间相机成像机理,给出了焦面像移速度以及由视轴角误差引起的像移速度匹配误差计算公式,分析了视轴角对地面像元分辨力的影响。并以调制传递函数(MTF)为约束条件给出了不同积分级数下视轴角的范围。通过实际工程参数计算得出,当视轴角控制误差为0.8时,满足96级TDICCD成像质量要求的视轴角应不大于12.75;若要满足96级TDICCD倾斜成像时视轴角达到25,则视轴角控制误差应优于0.4。     

Dynamic rotational characteristics of actinides on empirical approach

In the paper calculation of the moments of inertia for nuclei from the region 87 ≤ Z ≤ 100 and 130 ≤ N ≤ 156 was made in dependence on the angular momentum of their rotational states. The experimental values of the moments of inertia were calculated for rotational energy of the classic rotor in its quantum form, with the use of a simple formula. The moment of inertia term appearing in the formula was treated as a variable. The calculations were carried out on the basis of experimental data for the energies of the rotational levels for 51 bands built on ground states for even-even nuclei and for nuclei with odd mass number A. In addition, 30 rotational bands built on excited states were also analysed in the investigated region in case of even-even nuclei. For many bands and nuclei the considered dependence of the moment of inertia on angular momentum has been found in the analytical form by fitting polynomials to the experimental data. It turned out that obtained results for the moments of inertia made it possible to describe the energies of rotational levels with a relative deviation not greater or only slightly greater than 1%. In general, in the case of 12 bands of ground level the maximum relative deviation of obtained level energies is smaller than 1%.      

Matlab软件在三线摆法测定圆环转动惯量中的应用

使用三线摆可以测量圆环的转动惯量,但测量的物理量较多,人工处理数据比较繁琐,且容易出错。因此,本文使用Matlab软件处理数据。把测量的实验数据输入Excel表格中,引入Matlab软件中运行相关程序后可以直接得到圆环的转动惯量,以及测量的百分差和相对不确定度,处理过程快捷精确。