摘要
文中讨论的扭振法转动惯量测量仪,不需要测量幅值,根据振荡周期就能给出高精度的转动惯量计算结果。介绍了它的工作原理,并且详细分析了测量系统的误差,并给出了相邻周期误差的估计公式。在此基础上提出了两种数据处理方法,方法Ⅰ针对小阻尼比采用对偶时间序列误差相消,直接计算;方法Ⅱ通过计算阻尼比,把阻尼振荡周期转化为无阻尼自振周期进行转动惯量计算,放松了对阻尼比的要求,提高了计算精度。数学仿真结果表明,两种方法对测量误差都不敏感,且均可满足测量误差<±0.5%的要求。
Based on the principle of the inverted torsion pendulum, a moment of inertia (MOI) measuring instrument is discussed. Without measuring its amplitudes, the high accuracy results can be obtained only using the period of the oscillation. The principle is explained and the errors of measuring system are discussed in detail. Consequently, a set of formulas is deduced to calculate the differences of the neighbor periods. Based on them, two approaches dealing with the experimental data are proposed and analyzed. The first one that is suitable for a little damping ratio handles data directly and the errors are counteracted with two sets of time serials. The second one calculates damping ratio at first, and then non-damping oscillation period is transformed from damping one to obtain MOI. As a result, damping ratio constraint is decreased and the precision is increased. At last the simulations show that the approaches are insensitive to errors of measurement and satisfy the requirement for error <±0.5 %.
出处
《计量学报》
CSCD
北大核心
2004年第3期250-253,共4页
Acta Metrologica Sinica
关键词
计量学
转动惯量
摆动周期
测量误差
Metrology
Moment of inertia
Period of oscillation
Measuring error
