MinGeo Cableless DI Digital Station (DS) absolute instruments
Absolute magnetic measurements are performed by a classical theodolite equipped with single-axis
magnetometer known as declination inclination magnetometer (DIM).
At MinGeo company we developed a new kind of cableless, digital, DIM instrument, named as
MinGeo Declination Inclination Digital Station.
In the DS instrument an electronic theodolite, a single-axis fluxgate sensor, a tablet and a DS
android application are integrated together.
All steel and all inner optical parts of the original theodolite are removed and the original graduated circles are replaced by new glass circles of a digital angle encoder. The vertical encoder chip is fixed on the pendulum of the theodolite to eliminate reading differences caused by small levelling errors. The digital angle encoder uses a laser beam to scan precise graduation marks on a circular glass scales.
DS is based on refurbished and converted to steel free Zeiss theodolite. The single axis fluxgate sensor is fixed on the telescope and connected to a MinGeo DS electronics. Simple construction and low power consumption of the electronics allows to put it together with its battery into a small box and fix on the telescope. This way everything moves together with the sensor during the measurement procedure and its any magnetic moment is cancelled. Measurement data are transmitted to a tablet via Bluetooth 4.0 BLE to ensure easy operation and data recording/processing. Measurement is inicialised can be sent by a small nonmagnetic remote controller.
A large screen tablet is used to display and store UTC timestamp, fluxgate sensor, horizontal and vertical angular measurement values together with many additional data as session identifier, battery charge level of the magnetometer and of the tablet, actual and next telescope position, BT connection quality etc. All data stored in the tablet at the end of the measurement procedure data can be downloaded. The measurement range is ± 3000 nT. A bar display and an audio signal help the operator to find the measurement range. The DS electronics, tablet and remote controller can be charged from 5V DC.
Major advantages of using DS over the conventional DIMs are:
- Observer work is carried out quicker
- Accuracy of measurement is higher
- Personal errors involved in angle reading and recording are eliminated
- Calculation of magnetic meridian is automatic and accurate
- There is a template manager to assist observer
- Enables more sophisticated absolute measurement routines
- Preliminary data processing is provided
- 10" tablet + DS Android application
- remote controller
- sunfilter for telescope
- simple nonmagnetic servicing tools
- universal charger
- plastic transport box
- wooden steel-free tripod
- industrial tablet
Main technical parameters:
- Angular resolution: 5" = 1.5 mgon
- magnetic resolution 0.1 nT
- Magnetic scale factor with tolerance: 1.0 ± 3% unitless
- Fluxgate sensor alignment better than ± 3' = ± 55.6 mgon
- Instrument offset better than ± 10nT
- Instrument operation time: 8+ hours
- Operating temperature: 0 ºC to +40 ºC
- Height of instrument: 33.4 cm
- Height of tilting axis: 22.4 cm
- Container: 55x65x35 cm
- Tripod: 16x16x160 cm
- Instrument: 4.8 kg
- Instrument in plastic container: 9.2 kg
- Tripod: 5.6 kg