MICROTESLA DIGITIZED SENSORS

General Description / Magnetometer / Accelerometer / Digital Interface / Power Supply Section / Calibration / Specifications

General Description

The MicroTesla Digitized Sensor combines an analog-to-digital converter with MicroTesla’s proprietary directional sensor technology to provide a digital output directional measurement solution. The sensor is designed to allow direct connection to a microprocessor based data acquisition system via dedicated serial interface connections. The magnetometer, accelerometer and associated electronics are all mounted on a rigid one piece chassis. A variety of end connections are available to meet customer specific requirements. The ruggedized sensor design is well suited to Measurement-While-Drilling and Oil Field Wireline applications.

Magnetometer

The three-axis magnetometer used in the sensor is a MicroTesla proprietary flux gate design. The magnetometer design uses proprietary sampling and filtering methods which make it particularly suitable for operation over wide temperature ranges. Over the specified operating range, the magnetometer outputs are almost linear and very repeatable. Low bias and scale factor variations versus temperature virtually eliminates the need for the third order temperature corrections.

Accelerometer

Three single-axis accelerometers are provided. These ruggedized quartz flexure servo devices have been used successfully in Measurement-While-Drilling applications.

Digital Interface

The digital interface consists of a serial analog-to-digital converter used to measure the three-axis magnetometer outputs, the three axis accelerometer outputs, the sensor temperature and one user specified channel. The digital interface also has a serial non-volatile memory for storage of a user specified K-factor table. Several options exist for interface to the customer’s microprocessor based data acquisition system. The analog-to-digital converter and non-volatile memory may be controlled directly via multiple serial input/output connections. Alternatively, control and data acquisition may be accomplished via serial interface connections to a UART port on a dedicated micro-controller.

Power Supply Section

The optional power supply is a high temperature design with options to allow operation from a variety of customer supplied DC power sources. Typically, this power source is either a Lithium battery pack and/or an alternator power source.

Calibration

MicroTesla can calibrate the complete sensor package and will provide the K-Factor table in a customer specified format.