Application Examples of Gyro Theodolite

Principle

Gyro theodolite is an instrument used to measure true north azimuth by combining gyroscope and theodolite through connecting mechanism. It uses the physical characteristics of the gyroscope itself (fixed axis and precession), the sensitive part of the gyroscope with the center of gravity moved down is used to sensitive the horizontal component of the earth's rotation angular velocity, and under the action of gravity, a northward precession moment is generated, so that the gyroscope spindle swings around the Earth's meridian plane, so as to determine the true north azimuth.

Classification

The gyrotheodolite can be divided into engineering class (orientation accuracy beyond 10 ") and precision class (orientation accuracy within 10 ") according to orientation accuracy. Represented by the ER-GT-02 ultra-precision gyrotheodolite, its orientation accuracy is less than 3.6 "(1σ), with an integrated body design (built-in battery), compact structure and stable performance. It has the functions of low position locking, automatic zero observation, automatic north finding, automatic limit, wide temperature compensation, etc. It provides the north finding accuracy of the reference plane azimuth and reduces the north finding time.

The gyro theodolite consists of a gyroscope, a theodolite and a tripod. Gyroscope is the core of theodolite. According to the principle of gyroscope, the gyroscope axis can accurately indicate the true north direction under the combined action of the gravity of the sensitive part of the gyroscope itself and the rotation of the earth, and read the direction on the theodolite level disk. The gyroscope can determine the true meridian direction and the deviation from the vertical line, and can measure the declination Angle, angular velocity and acceleration of the moving object. In addition to the zero-bias stability requirements for gyroscopes, the ER-MG2-022 is a high temperature north seeking MEMS gyroscope capable of operating at a 5 V power supply and a wide temperature range (−45°C to +125°C). The theodolite is the azimuth extraction device of the system, and it can also measure the geographical azimuth or coordinate azimuth of the target by aiming at the target. The theodolite has a self-collimation function to facilitate measurement and calibration operations. Usually, the theodolite has a serial communication interface, which can realize serial data communication with the gyroscope and the command system. The tripod provides support for the gyro theodolite.

Applications

Measurement of the center line of a folded tunnel

In the tunnel and other excavation engineering, the long distance wire which is difficult to ensure the accuracy is generally used in the measurement of the center line in the pit. Especially for the situation of shield excavation, from the short baseline datum line of the vertical pit, we must have high angle measuring accuracy and displacement accuracy. In the survey, we should regularly check the ground and underground corresponding to ensure the accuracy of the survey. Especially in dense urban areas, it is not possible to carry out too much testing and encounter difficulties. If the gyro theodolite is used, the azimuth datum with absolute high accuracy can be obtained, and it can reduce the expensive testing operation (the least checkpoint). It is a highly efficient centerline measurement method.

Foldable direction angle acquisition

When visibility barriers cannot obtain the direction angle from a known point, astronomical measurement method can be used to obtain or gyro theodolite orientation angle (according to the measurement standard of construction). Compared with the astronomical survey, the gyro-theodolite measurement has many advantages: less dependence on weather, no more cloud, no complicated astronomical computation, and any angle of survey line, and easy to calculate closure error.

Folding North determination

Height limitation or shade sunshine conditions on the high-rise buildings in the city or suburban area. In the construction of the application, to attach the shadow map. This image refers to 8 points in the winter solstice when the sun really to 16 as a benchmark for high precision north direction, in order to calculate, drawing required determination. The use of gyro theodolite measurement can obtain true measurement time effect is not affected by weather.

For more information, please feel free to contact info@ericcointernational.com