The Design And Implementation Of A Rapid And Low-cost North-finder

According to the characteristics and requirements of the work carrier the new boreholecomponent strainmeter, this paper presents a fast and low-cost North-finder with errorcompensation,which has a wide range of application.This Device find magnetic bynorth geomagnetic directional principle to achievedirectional function. Inview of the inevitably error problems in actual measurement ofelectroniccompass, based on analyzing theworking principleofelectroniccompassandcompasserror generation mechanism, this paper establishesacompassheading error compensationmodel,proposes theelectronic compass errorcalibrationand compensation method.Using the least square fittingmethodbased on ellipsehypothesis for theerror model, according to theproperties ofellipticalgebraexpressions,identify constraintsof the ellipse,thentheproblem ofsolvingellipticparameterswould transfer to extremum problems of constraintconditions,andultimately determine theparameterfor fitting ellipseand completethecompensationprocess.Aiming at the decline of ellipse fitting algorithmaccuracy whenlargeattitude angleorinterference exist, proposedcorrectionmethod based on radial basisfunction(RBF)neural network.Then,this paper analyzes scheme and realization and function design oftheoveralldesignand the functional modulesfrom the perspective of software and hardware.Anelectronic compass is used as azimuth measurement sensor in this device. A translocationmotor is utilized to adjust the attitude of the device and its carrier, and through thesteppermotor to completethe calibrationaction. To realizethe error ellipse coefficient compensationalgorithmbased on the assumption by lower computer programming, and achieve thefunction approximation for error compensation based on RBF neural network by MATLABtoolbox method.Controlled by single chip microcomputer, the system could collect thebearing measurements, operate translocation motor automatically and intelligently, andprocess and store the orientation data.Finally,through fieldmeasurement andsimulation analysis to verified the correctnessandeffectiveness of the electroniccompass errorcompensation algorithm,motor controlalgorithm anddirectional theoverall function andperformance of the North-finder.