1. Manuals
  2. Brands
  3. LORD Manuals
  4. Receiver
  5. MicroStain 3DM-GX5-45
  6. User manual

LORD 3DM-GX5-45 User Manual

Gnss-aided inertial navigation system (gnss/ins)
Hide thumbs Also See for 3DM-GX5-45:
Table of Contents

Advertisement

Quick Links

Download this manual
LORD USER MANUAL
3DM-GX5-45
GNSS-Aided Inertial Navigation System (GNSS/INS)

Advertisement

Table of Contents
loading

Related Manuals for LORD 3DM-GX5-45

Summary of Contents for LORD 3DM-GX5-45

  • Page 1 LORD USER MANUAL 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS)
  • Page 2 ® MicroStrain Sensing Systems 459 Hurricane Lane Suite 102 Williston, VT 05495 United States of America Phone: 802-862-6629 www.microstrain.com sensing_support@LORD.com sensing_sales@LORD.com Copyright © 2017 LORD Corporation ® ® ™ ® ® ® ™ ™ ™ , 3DM-DH , 3DM-DH3 , 3DM-GX1...

  • Page 3: Table Of Contents

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Table of Contents System Overview Sensor Overview 2.1 Components 2.2 Interface and Indicators Basic Setup and Operations 3.1 Software Installation 3.2 System Connections 3.3 Software Interface 3.3.1 Interactive Help Menu 3.4 Sensor Communication 3.5 GNSS Satellite Link...
  • Page 4 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 5.2 Tare Mounting Pitch-Roll 5.3 Magnetometer Auto Calibration 5.3.1 Enable 5.3.2 Capture 5.4 Magnetometer Manual Calibration 5.5 Estimation Filter Aiding 5.6 Heading Aiding Settings 5.6.1 Bias Convergence 5.7 Adaptive Anomaly Rejection 5.7.1 Gravity Adaptive 5.7.2 Mag Adaptive...
  • Page 5 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 7.1.2 Sensor Direct Mode 7.2 Sensor Wiring 7.3 Sampling on Start-up 7.4 Connecting to a Datalogger 7.5 Using Wireless Adapters Troubleshooting 8.1 Troubleshooting Guide 8.2 Repair and Calibration 8.3 Maintenance 8.4 Technical Support Parts and Configurations 9.1 Standard Configurations...

  • Page 6: System Overview

    The LORD Sensing MIP Data Communications Protocol that is used to communicate with LORD Sensing inertial sensors is also available for users who want to develop customized software solutions. Because of the unified set of commands across the sensor family, it is easy to migrate code from one inertial sensor to another.

  • Page 7: Sensor Overview

    Auto-Adaptive Extended Kalman Filter (EKF), allows the 3DM-GX5-45 to perform well in a wide variety of applications that require low noise, drift, gain, and offset errors. Uncertainty monitoring, scale factor estimation, and bias estimation outputs are available.

  • Page 8: Components

    User Manual 2.1 Components The 3DM-GX5-45 Inertial Sensor can be purchased by itself or with a Connectivity Kit. All software, drivers, and links to detailed documentation are included with the sensor purchase. For a complete list of available configurations, accessories, additional system products, and ordering information, Parts and Configurations on page 63  .

  • Page 9: Interface And Indicators

    The sensor is installed using the mounting and alignment holes as needed see Sensor Mounting on page 50 The indicators on the 3DM-GX5-45 include a device status indicator and the device information label. Table 2 - Indicator Behaviors describes the basic status indicator behavior.

  • Page 10: Basic Setup And Operations

    If magnetization is suspected, use a degaussing tool to demagnetize. To acquire sensor measurements and computed outputs, the 3DM-GX5-45 uses a host computer, a communications port, and applicable software.  The LORD Sensing MIP Monitor software is provided with the system and includes all functions needed for sensor configuration and data acquisition.

  • Page 11: Software Installation

    User Manual 3.1 Software Installation NOTE The MIP Monitor Software Suite includes hardware drivers required for 3DM-GX5-45 sensor operation.  Sensors will not be recognized without these drivers installed. To Install the MIP Monitor software on the host computer, complete the following steps: 1.

  • Page 12: System Connections

    ( see Specifications on page 67 To acquire sensor data the following components are needed: 3DM-GX5-45 sensor, communication cable, power cable (as applicable for RS232 communications), GNSS antenna, GNSS non-magnetic antenna adapter cable, and a host computer with LORD Sensing MIP Monitor installed.

  • Page 13: Software Interface

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 3.3 Software Interface The MIP Monitor software includes a main window with system information and menus, a device settings window ( see Sensor Settings on page 16 ), and several data monitoring windows (...

  • Page 14: Interactive Help Menu

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 3.3.1 Interactive Help Menu MIP Monitor also includes a mouse-over feature that provides explanations of the information and settings. This feature is enabled by selecting the question mark icon or Help button in any window.

  • Page 15: Sensor Communication

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 3.4 Sensor Communication Once power has been applied to the sensor, it is functional. The sensor selects the appropriate serial communication (USB or RS232) on power-up based on which cable is connected. If the hardware drivers have been installed, communication can be established using the MIP Monitor software...

  • Page 16: Gnss Satellite Link

    The GNSS antenna requires unobstructed line of sight with the sky in order to achieve communication with the GNSS satellites. Communication between the GNSS receiver and GNSS satellites is initiated when the 3DM-GX5-45 is first powered on. The receiver will continuously search for satellites until a link is established. When the link is established, the GNSS Monitor window in the MIP Monitor software will display the satellite and...

  • Page 17: Saving Configurations

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Figure 9 - Device Settings Menu 3.6.1 Saving Configurations Sensor settings are saved temporarily by selecting the OK button in the Device Setup window after configuration, but they are lost when the device is powered off. To save current settings so they are automatically restored the next time the device is powered on, select Settings >...
  • Page 18 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Figure 10 - Save Sensor Settings...

  • Page 19: Data Monitoring And Recording

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 3.7 Data Monitoring and Recording Throughout the MIP Monitor views the same icons are used to control data streaming (sampling) and recording. These icons can be found in the MIP Monitor main window icon toolbar and in each data monitoring window.
  • Page 20 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual correctly or to view the outputs in near real time. If sensor setup has already been confirmed, streaming and recording can be initiated from the main window. Figure 12 - Data Streaming is an example of Sensor Data Monitoring, which displays the selected IMU/AHRS measurements.
  • Page 21 NOTE If the data is recorded in Binary format it will require a translation program that utilizes the LORD Sensing MIP Data Communications Protocol to make it user-readable. Figure 13 - Data Recording 6. To end recording press the Arm Recording button again, and select OK in the confirmation prompt window.

  • Page 22: View Recorded Data

    CSV files can be viewed with Microsoft Excel, Quattro Pro, Open Office, or other CSV editors and spreadsheet programs.  Data recorded in Binary format requires a translation program utilizing the LORD Sensing MIP Data Communications Protocol to make it user-readable. NOTE Data in the data files is displayed in time sequence.

  • Page 23: Sensor Measurements

    GNSS Computed estimations for position, velocity, and attitude (PVA) are available outputs on the 3DM-GX5-45. To achieve these estimations, the MEMS sensors and GNSS solution are blended together in a loosely- coupled Extended Kalman Filter on a dedicated filter processor .

  • Page 24: Direct Sensor Measurements (Imu Outputs)

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 4.1 Direct Sensor Measurements (IMU Outputs) The sensors in an Inertial Navigation System (INS), from which measurements for navigation and orientation are obtained, are collectively known as the Inertial Measurement Unit (IMU). These sensors are arranged on the three primary axes (x, y, and z) to sense angular rate, acceleration, and the local magnetic field.
  • Page 25 User Manual Table 3 - IMU Measurements lists the IMU measurements available for the 3DM-GX5-45. Additional measurement units may be available in MIP Monitor for some outputs, however they are converted values and do not represent the actual sensor outputs. Only actual output units are listed.

  • Page 26: Computed Outputs

    4.2 Computed Outputs (Estimation Filter) The computed outputs are measurements from the 3DM-GX5-45 IMU sensors and GNSS receiver that are blended through an Extended Kalman Filter (EKF) algorithm. The Kalman Filter produces a better estimation of position, velocity, and attitude (PVA) outputs than can be achieved by the inertial sensors or the GNSS individually.
  • Page 27 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual To view and record Estimation outputs, see Basic Setup and Operations on page 10 Measurement Units Description indicates the current state of the EF, such Filter Status as running or initializing GNSS time corresponding to the calculated GPS Time weeks &...
  • Page 28 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Measurement Units Description WMM (World Mag- WMM local magnitude, inclination and Gauss netic Model) declination based on GNSS coordinates Pressure Altitude meters (altitude) altitude estimate from barometric pressure meters (altitude)pressure altitude as derived from the U.S. Standard...

  • Page 29: Sensor Reference Frames

    The World Geodetic System is the standard for cartography and navigation. The latest revision, WGS84, is the reference coordinate system for GPS, and the 3DM-GX5-45 reports position using this coordinate frame. It also calculates the magnitude of the local gravity vector using the WGS84 reference formulas.

  • Page 30: North East Down (Ned) Frame

    For most applications, this assumption is valid and provides a more intuitive reference frame for expressing velocity and attitude information than a global frame. The 3DM-GX5-45 reports velocity in this frame and attitude with respect to this frame. Figure 18 - North East Down Frame...

  • Page 31: Sensor Frame

    Device Settings > EF settings > Geographic. Refer to the 3DM-GX5-45 dimensional diagram for the location of the measurement origin ( Reference Diagrams on page 71 Figure 19 - Sensor Frame...

  • Page 32: Platform Frame

    User Manual 4.3.4 Platform Frame The 3DM-GX5-45 includes the option to define an orientation transformation and offset distance from the sensor frame to a user-definable platform frame. This is useful when the sensor cannot be mounted in the same location or orientation as the desired reference point on the platform frame.
  • Page 33 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual In the MIP Monitor software the transformation and offset settings are entered at: Settings > Device Figure > Estimation Filter > Mounting in the Mounting Offset and Mounting Transformation fields ( 21 - Platform Frame Settings ).

  • Page 34: Performance Optimization

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Performance Optimization 5.1 Gyroscope Bias Gyroscope biases (offsets) can be zeroed out to set a baseline value for the static home position and conditions in the application. This should be done after sensor installation.

  • Page 35: Tare Mounting Pitch-Roll

    This function captures the current pitch-roll orientation of the device and sets it as the level reference, providing a convenient way to set the sensor to vehicle frame transformation. For more information on the corresponding LORD Sensing MIP Data Communications Protocol command, see the (Data Communications Protocol Manual)   .

  • Page 36: Magnetometer Auto Calibration

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 5.3 Magnetometer Auto Calibration 5.3.1 Enable Enabling the EF Mag Hard Iron Auto Calibration allows estimation of the magnetometer bias (bias tracking) for purposes of auto- calibration. Enabling the EF Mag Soft Auto Calibration allows estimation of the magnetometer scale factor (scale factor tracking) for purposes of auto-calibration.

  • Page 37: Capture

    These maneuvers are necessary to establish the magnetometer offset and scale factors. For more information on the corresponding LORD Sensing MIP Data Communications Protocol command, see the (Data Communications Protocol Manual) To capture, select the sensor name in the MIP Monitor software main window, then select Settings...

  • Page 38: Magnetometer Manual Calibration

    However, often these sources are hard to avoid or are hidden. To mitigate this effect when using the 3DM-GX5-45 magnetometer to aid in heading estimations, a field calibration of the magnetometer after final installation is highly recommended. This can be...
  • Page 39 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 3. The sensor should automatically appear in the sensor list. If not, use the Refresh button to Figure 26 - Sensor Menu query it and then select the sensor (   ). 4. Select the Arm Recording button next to Collect Data. The software will begin taking readings, as indicated by the points counter in the graphing window.
  • Page 40 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual are present but only if enough data points can be collected in all quadrants. If the range of motion is restricted in one dimension, the Spherical Fit may be the best choice. If there are enough points in all dimensions, the Ellipsoid Fit may be better.

  • Page 41: Estimation Filter Aiding

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 5.5 Estimation Filter Aiding There are four primary categories with sub-menus in each to customize GNSS,heading , pitch-roll, and altitude . To enter the Estimation Filter Aiding menu, select the sensor name in the MIP Monitor software main window, then select Settings >...

  • Page 42: Heading Aiding Settings

    5.6 Heading Aiding Settings Device settings are stored in the sensor memory. Only the configuration options that are available for the type of sensor being used are displayed in the configurations menus. The 3DM-GX5-45 has eight heading options. If the setting is an external reference, the user has to provide a heading reference (for example, GPS External Receiver on page 1...

  • Page 43: Bias Convergence

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 5.6.1 Bias Convergence Accurate estimation of the biases can take several minutes to converge, therefore after the filter is initialized, the free-inertial performance will continue to improve until the bias estimations settles.

  • Page 44: Mag Adaptive

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Figure 31 - Gravity Adaptive Settings 5.7.2 Mag Adaptive Enabling this feature will allow the filter to reject magnetometer readings when the magnitude error exceeds the high limit (in m/s ^ 2). The bandwidth (in Hz) sets the cutoff frequency of the low pass...

  • Page 45: Angular Rate And Acceleration Limits

    Figure 32 - Mag Adaptive Settings 5.8 Angular Rate and Acceleration Limits The 3DM-GX5-45 angular rate and acceleration ranges depend on the sensors installed in the device. Exceeding the specified range for either sensor will result in estimated state errors and elevated uncertainties until the over-range event is corrected and the filter can resolve the errors.
  • Page 46 Kalman filter. The 3DM-GX5-45 runs a loosely-coupled Extended Kalman Filter. In a loosely-coupled filter, the inertial sensors in the IMU are used to propagate the state estimation at a high rate (500 Hz); whereas the GNSS position and velocity measurements are used to periodically correct the state (4 Hz.) This...

  • Page 47: Estimation Filter Convergence

    (such as when mounting the 3DM-GX5-45 on a gimbal close to the frame of a ground vehicle). The Kalman filter estimates the full states of position, velocity, attitude, and sensor parameters for a total of 34 states: 3 position, 3 velocity, 4 attitude (quaternion), 3 accel bias, 3 gyro bias, 3 accel scale factor, 3 gyro scale factor, 9 magnetometer, and 3 GNSS antenna offset error states.

  • Page 48: Output Uncertainty

    5.12.2 Output Uncertainty The 3DM-GX5-45 estimation data set includes a filter status field that contains a set of status flags. These flags pertain to high covariance values for position, velocity, attitude, and inertial sensor parameters. These flags should be monitored and cross- checked against the corresponding uncertainty fields when they appear.

  • Page 49: Import And Export Settings

    The import and export settings features provide a consolidated file of the user settings, enabling Device Settings information to be saved and shared. For example, exporting settings to the LORD technical support team helps facilitate fast and accurate resolution of technical issues.

  • Page 50: Sensor Installation

    GNSS receiver, the GNSS antenna connector on the side of the sensor must be accessible. The connector and cable must be non-magnetic. The MMCX to SMA adapter cable supplied with all 3DM-GX5-45 is non-magnetic. The sensor has two mounting tabs with holes for fastening.  Mounting screws should be 300 Series stainless steel.

  • Page 51: Oem System Integration

    For these applications the 3DM-GX5-45 is available as a stand- alone component with optional interface connectors. The communication protocol used for configuring and acquiring sensor data and estimations outputs is available for these applications as well.

  • Page 52: Packet Builder

    7.1.1 Packet Builder To expedite program development, a packet builder tool is included in the MIP Monitor software. The packet builder allows users to send multiple packets to the 3DM-GX5-45 and view the resulting reply data. Applicable protocol structure and design is described in the 3DM-GX5-45 LORD Sensing MIP Data Communications Protocol Manual ...

  • Page 53: Sensor Direct Mode

    When in Sensor Direct mode the device normal functionality is not available. The protocol commands used to interface with the IMU are a subset of the standard LORD Sensing MIP Data Communications Protocol and are further described in the LORD Sensing MIP Data Communications Protocol manual.

  • Page 54: Sensor Wiring

    Connect only one at a time. Observe connection polarity. Sensor power and serial communications cables are available from LORD Sensing and come with the sensor starter kits. These cables will have the micro-DB9 connector on one end (to connect to the sensor) and either a standard DB9 on the other end (for RS232 communication) or a USB connector (for USB communications).

  • Page 55: Sampling On Start-Up

    This can be useful in sensor integration applications in which immediate data acquisition is desired, and connection to MIP Monitor for data logging is not required. This functionality can also be embedded in user- designed applications by using the corresponding LORD Sensing MIP Data Communications Protocol command.

  • Page 56: Connecting To A Datalogger

    Many inertial applications incorporate dataloggers of all different types to collect and distribute sensor outputs. For more information and examples refer to the "Using Dataloggers with Inertial Sensors" Technical Note on the LORD Sensing website, or contact LORD Sensing Technical Support ( Technical Support on page 62 7.5 Using Wireless Adapters...

  • Page 57: Troubleshooting

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Troubleshooting 8.1 Troubleshooting Guide...
  • Page 58 NOTE: if the baud rate is set higher than the computer serial port is capable of reading, communication will be permanently lost with the device. To recover, it will need to be connected to a higher speed port, connected via USB cable, or sent to LORD...
  • Page 59 If no conclusion can be determined, or to send a device in for repair, contact LORD Sensing Technical Support ( See Technical Support on page 3.1 sampling settings are incorrect...
  • Page 60 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Problem Possible cause and recommended solution the LORD Sensing MIP Data Communications Protocol to make it readable. 3.6 sensor has been magnetized Contact or close proximity with magnets may disrupt the sensor operation and cause magnetization of internal components, which can affect magnetometer performance.

  • Page 61: Repair And Calibration

    LORD Sensing model number and serial number, as well as your name, organization, shipping address, telephone number, and email.  Normal turn- around for RMA items is seven days from receipt of item by LORD Sensing . Warranty Repairs LORD Sensing warrants its products to be free from defective material and workmanship for a period of one (1) year from the original date of purchase.

  • Page 62: Technical Support

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 8.4 Technical Support There are many resources for product support found on the LORD website including technical notes, FAQs, and product manuals. http://www.microstrain.com/support_overview.aspx For further assistance our technical support engineers are available to help with technical and applications questions.

  • Page 63: Parts And Configurations

    User Manual Parts and Configurations 9.1 Standard Configurations For the most current product information, custom, and OEM options not listed below, refer to the LORD Sensing website or contact the LORD Sensing Sales Department. Table 5 - Model Numbers describes the standard models available at the time this manual was published.
  • Page 64 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual The same options are available in each model, and are indicated in the last four digits of the product part number. For a list of the starter kit contents,(  see Components on page 1...

  • Page 65: Accessories

    User Manual Accessories The following parts are available for use with the 3DM- GX5 - 45. For the most current product information refer to the LORD Sensing website or contact the Sales Department. ( see Sales Support on page 66   ).

  • Page 66: Sales Support

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 9.3 Sales Support Products can be ordered directly from the LORD Sensing website by navigating to the product page and using the Buy feature.  http://www.microstrain.com/inertial For further assistance, our sales team is available to help with product selection, ordering options, and questions.

  • Page 67: Specifications

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Specifications General Triaxial accelerometer, triaxial gyroscope, triaxial Integrated magnetometer, pressure altimeter,temperature sensors and sensors GNSS receiver Inertial Measurement Unit (IMU) outputs: acceleration, angular rate, magnetic field , ambient pressure, deltaTheta, deltaVelocity Computed outputs:...
  • Page 68 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Resolution < 0.1 m Noise density 0.01 hPa RMS Sampling rate 25 Hz...
  • Page 69 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Computed Outputs Position accuracy ±2 m RMS horizontal, ± 5 m RMS vertical (typ) Velocity accuracy ±0.1 m/s RMS (typ) EKF outputs: ±0.25° RMS roll and pitch, ±0.8° RMS heading (typ) Attitude accuracy CF outputs: ±0.5°...

  • Page 70: Safety Information

    This section provides a summary of general safety precautions that must be understood and applied during operation and maintenance of components in the LORD Sensing Inertial Sensor Products.  Throughout the manual, ANSI Z535 standard safety symbols are used to indicate a process or component that requires cautionary measures.

  • Page 71: Addendum

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Addendum 12.1 Reference Diagrams The diagrams in this section are to intended to aid in product installation and troubleshooting. For more information contact LORD Sensing Technical Support ( see Technical Support on page 62 12.1.1 Sensor Dimensions and Origin...

  • Page 72: Gnss Antenna Specifications

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 12.1.2 GNSS Antenna Specifications These specifications describe the GNSS antenna included in the 3DM-GX5-45 connectivity kit. Physical Specifications Construction ASA plastic Dimensions 38 mm x 38 mm x 14.3 mm Weight 50 g (without cable and connector)

  • Page 73: Power Supply Specifications (Rs232 Kits Only)

    User Manual 12.1.3 Power Supply Specifications (RS232 kits only) The power supply is only required for the RS232 devices. These specifications describe the power supply included in the 3DM-GX5-45 connectivity kit. Operating Parameters AC input voltage rating 100 to 240 V ac...

  • Page 74: Communication And Power Cables

    User Manual 12.1.4 Communication and Power Cables These diagrams describe the cables included in the 3DM-GX5-45 connectivity kits. Only one is included in each kit, depending on the type of kit ordered. Figure 41 - RS232 Communications and power cable...
  • Page 75 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Figure 43 - Connecter interface cable (sold separately, PN: 6224-0100)

  • Page 76: Reference Documents

    User Manual 12.2 Reference Documents Many references are available on the LORD Sensing website including product user manuals, technical notes, and quick start guides.  These documents are continuously updated and may provide more accurate information than printed or file copies. ...

  • Page 77: Glossary

    3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual 12.3 Glossary A/D Value The digital representation of analog voltages in an analog-to-digital (A/D) conversion. The accuracy of the conversion is dependent on the resolution of the system electronics. Higher resolution produces a more accurate conversion.
  • Page 78 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Attitude the orientaion of an object in space with reference to a defined frame, such as the North-East-Down (NED) frame Azimuth A horizontal arc measured between a fixed point (such as true north) and the vertical circle passing...
  • Page 79 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Delta-Theta the time integral of angular rate expressed with refernce to the device local coordinate system, in units of radians Delta-velocity the time integral of velocity expressed with refernce to the device local coordinate system, in units of...
  • Page 80 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual Host (computer) The host computer is the computer that orchestrates command and control of attached devices or net- works. Inertial Measurement System Inclinometer device used to measure tilt, or tilt and roll...
  • Page 81 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual NED (North-East-Down) A geographic reference system acronym for Original Equipment Manufacturer Offset A non-zero output signal of a sensor when no load is applied to it, typically due to sensor imperfections. Also called bias.
  • Page 82 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual acronym for Root Mean Squared Roll In navigation roll is what occurs when a horizontal force is applied at a distance right or left from the cen- ter of gravity of the platform, causing it to move side to side with respect to the sensor or platform frame origin.
  • Page 83 3DM-GX5-45 GNSS-Aided Inertial Navigation System (GNSS/INS) User Manual UTC (Coordinated Universal Time) The primary time standard for world clocks and time. It is similar to Greenwich Mean Time (GMT). Vector a measurement with direction and magnitude with refernce from one point in space to another Velocity The rate of change of position with respect to time.

Table of Contents