The Measurement Research Of The Swing Angle Of Balance Beamn Based On The Balance Oscillation System

Based on fundamental physical constants to define a new SI system in the process of implementing quality quantum benchmark is the most important, is also the most difficult, is one of the focus in the field of hot and difficult international metrology. International system of units of seven basic SI units, the unit of length m, time unit second unit ampere, temperature, current kelvin Moore, material quantity, unit, unit of luminous intensity candela have been realized the quantization and mass unit the kilogram is the only one still adopts the basic unit of the object reference. Physical benchmark accuracy can meet the demand of the scientific research, production, in addition, the rapid development of quantum physics, implement quality benchmark quantization has become an inevitable trend. The current domestic and foreign related research is mainly to define quality unit measuring basic physical constants, the fundamental physical constants of the most critical is Planck's constant. International metrology committee requirements, the quality of the implementation of quantum benchmark should have at least three separate scheme to measure Planck's constant. Quantum benchmark in today's world, the quality of the mainstream research method only two kinds, respectively is watt balance plan, silicon ball, and both the gravitational mass measurement, this paper mentioned the "swing cycle method" is a kind of measuring the quality of the inertial mass quantum benchmark the new scheme, because its principle is different from the watt balance plan, silicon ball, can be used as the third kind of independent, accurate measuring Planck's constant.Oscillation cycle method measuring Planck's constant scheme has gone through the original rational exploration stage, preliminary verified the feasibility of implementing the research plan. In this paper, the experiment adopted the motion of the device is an equal arm balance, has realized the loading weight of quality and its centroid, moment of inertia of decoupling, can avoid the motion of the traditional method of measuring the inertial mass, its center of mass is not easy to measure quasi defects. Oscillating balance system of equations of motion for the deduction, the process of the flat beam wobble, through analytical method, in-depth analysis of its motion state, the oscillating balance system of differential equations are obtained. Designed a model suitable for oscillating balance system of capacitive angular displacement sensor, is to realize the swing swing Angle balance beam of accurately measuring the necessary link, in view of the capacitance sensor and the actual situation of the balance beam, design the corresponding mechanical mechanism, guarantee the placement of capacitance sensor is reasonable, and realize the high and low position is adjustable, in order to ensure the capacitance sensor shielding window part of the center of the circle and swinging balance beam edge position. In view of the actual situation of the capacitive sensor measurement and needs, the corresponding Labview measurement program, realize the capacitance sensor capacitance value measurement and constantly according to the records. In combination with the practical situation of oscillating balance system, relevant experiment design, set up a measurement system, the measured results show that the capacitive angular displacement sensor linearity of 2.59×10-6, the sensitivity of 1.1× 10-6 pf/mg, retardation of the measurement point in 7 magnitude, 60 minutes, the stability of the output capacitance of 4.33×10-6.Which is used in the design of oscillating balance system of portable DC voltage reference, 2.5 hours of 10 V output voltage stability(relative standard deviation) can be less than 2×10-7, satisfy the high stability constant-current source of reference voltage requirements.