CN103105509A

CN103105509A - Nonlinear correction method of zero temperature drift of acceleration sensor

Info

Publication number: CN103105509A
Application number: CN2013100095083A
Authority: CN
Inventors: 王治国; 童晓华
Original assignee: SHANGHAI BULUE TECHNOLOGY Co Ltd
Current assignee: SHANGHAI BULUE TECHNOLOGY Co Ltd
Priority date: 2013-01-10
Filing date: 2013-01-10
Publication date: 2013-05-15

Abstract

Provided is a nonlinear correction method of zero temperature drift of an acceleration sensor. Zero deviation value of each acceleration sensor changes with different temperature deviation values, so precision of an acceleration magnitude is influenced to a great extent. The invention puts forward a correction method of zero temperature drift: first, arranging three specific correction temperature points according to a temperature working range which is required by precision; then recording three corresponding zero deviation values, evaluating a specific quadratic polynomial equation of one variable of the acceleration magnitude by conducting Lagrange's interpolation on three groups of values and obtaining the zero deviation values with temperature changes; finally choosing a specific temperature point for verification, comparing the real value of the zero deviation with the calculated value of the zero deviation so as to test whether the precision fits in with the specification. The nonlinear correction method of zero temperature drift of the acceleration sensor corrects the zero deviation of the acceleration sensor and necessarily improves precision and stability of the acceleration, especially the angle precision of measurement and application of an angle of inclination.

Description

The non-linear correction method that the zero point of acceleration transducer, temperature was floated

Technical field

This patent relates to the application of the accuracy correction of acceleration sensing technical field, particularly acceleration.

Background technology

Acceleration transducer is because have various in various degree skews with temperature zero point, so precision of its output accekeration can't ensure, is difficult to use in actual application environment again; Simultaneously, because zero migration value and temperature are not to be linear relationship, therefore take the method for linearity correction zero temperature skew, also can't really improve the precision of acceleration, satisfy practical application to the high-precision requirement of accekeration.

Summary of the invention

The object of the invention is to the zero migration value by the corrected acceleration sensor, improve significantly the precision of acceleration and ensure its stability.

The present invention is the non-linear correction method that zero point, temperature was floated of acceleration transducer.At first according to the temperature working range of accuracy requirement, two critical and normal temperature are set amount to three Tc points, then ask for three zero migration values corresponding to these three Tc points by the accekeration of output, for the nonlinear quadratic function, according to Lagrange's interpolation, obtain the specific quadratic polynomial function of this acceleration transducer, get final product to get temperature variant zero migration value, select at last specific two temperature point for verification, whether actual value and the calculated value of zero migration is up to specification to recently checking its precision.

Embodiment

Comprise calibration equipment, the description of trimming process and the method for inspection.

Calibration equipment:

Acceleration transducer is measured as high-precision tilt angle and is used, in operating temperature range under its angle precision requires, 3 Tc point environment are set, the requirement that arranges of 3 Tc points is, 1 high-temperature point (mxm. of working temperature), 1 normal temperature point (mean value in operating temperature range), 1 low temperature point (minimum of working temperature).

Trimming process:

Record out respectively zero migration value (Z0, Z1, Z2) and its corresponding temperature (T0, T1, T2) of acceleration transducer at 3 correcting mark fixed temperature points.Gather three groups of following quadratic interpolations of data substitution (lagrange polynomial), the particular constant k in computing function, m, n

L0＝Z0/((T0-T1)*(T0-T2))

L1＝Z1/((T1-T0)*(T1-T2))

L2＝Z2/((T2-T0)*(T2-T1))

Then draw k, m, n:

k＝L0*T1*T2+L1*T0*T2+L2*T0*T1

m＝-L0*(T1+T2)-L1*(T0+T2)-L2*(T0+T1)

n＝L0+L1+L2

With k, m, the nonlinear quadratic interpolation function of n substitution, the specific equation that just can obtain the temperature variant zero migration value of this acceleration transducer in whole operating temperature range is as follows:

Zc＝k+m×T+n×T ²

Zc wherein: acceleration zero migration value

T: working temperature

The method of inspection:

For guarantee to proofread and correct accurately, proofread and correct complete after, need to zero point temperature float check point and test apart from the temperature spot of maximum.(1 is the interim temperature value of proofreading and correct between high-temperature point and normal temperature point at 2 verification temperature spots, 1 is normal temperature point and proofreaies and correct interim temperature value between low temperature point) employing checks frock to carry out Zero calibration under Current Temperatures zero point, obtain test value, compare with the result of calculation of the zero migration computing formula of acceleration transducer, see whether meet the acceleration transducer system requirements that zero point, temperature was floated.

The present invention has accurately revised acceleration transducer zero migration, precision and its stability of acceleration have been improved to necessity, especially the angle precision of acceleration transducer in measurement of dip angle is used, be very suitable for high-end equipment as accurate core component technology, industrial automation, surveying instrument, the fields such as automobile.

Claims

1. the non-linear correction method that the zero point of an acceleration transducer, temperature was floated is characterized by and comprises following steps:

1.1 set specific three Tc points;

1.2 calculate the One-place 2-th Order polynomial equation of zero migration value and the temperature of acceleration transducer;

1.3 set specific two temperature point for verification, carry out the actual value of zero migration and calculated value to recently check.

2. the method in claim 1, step 1.1 is characterized as the setting of three temperature spots:

1 high-temperature point: the mxm. of working temperature;

1 normal temperature point: the mean value in operating temperature range;

1 low temperature point: the minimum of working temperature.

3. the method in claim 1, step 1.3 is characterized as the setting of two temperature spots:

First temperature spot: the correction high-temperature point in claim 2 and the interim temperature value between normal temperature point;

Second temperature spot: the interim temperature value between the normal temperature point in claim 2 and correction low temperature point.