Overview
Establishing the Sensor and Structure Azimuth will transform the orientation of the Northing/Easting and Transverse/Longitudinal Axis respectively. The Northing/Easting Axis will have to be established for sensors that measure displacement but do not inherently calculate North/East. Define this with Sensor Azimuth. The Transverse/Longitudinal Axis is a definable axis that allows you to point it in any desired orientation. Define this with Structure Azimuth. These settings are applicable for tilt measurement sensors like IPIs, Shape Arrays, and tiltmeters.
Structure and Sensor Azimuth are initially set to 0. This will default the Northing/Easting and Transverse/Longitudinal calculations to be aligned with the Y/X axis as seen below:
Sensor Azimuth will always be measured by locating the direction of the Y-axis. To determine the Y axis on your sensor, each sensor will likely have a physical indicator on it to help you visualize it. If not, see the sensor details to find out what is the direction of your Y-axis.
This article will cover:
Sensor Azimuth - Northing/Easting
In a sensor that does not inherently calculate North/East, in order for the Northing and Easting calculations to represent true Northing and Easting, you will need to enter the sensor azimuth. Sensor Azimuth is the number of degrees the Y-Axis is from North in a clockwise direction. See the examples below for common orientations.
Use a compass to measure how many degrees the indicator is from north to find the sensor azimuth.
Structure Azimuth - Transverse/Longitudinal
The Transverse and Longitudinal axis will point in a direction that is dependent on the Structure Azimuth entered. This is a definable axis that allows you to point it in any desired orientation. It is useful for finding movement in the direction of a specific structure or any point of reference. Transverse+ will point in the direction defined by Structure Azimuth. Azimuth is the number of degrees measured from North, clockwise.
*Note: North/East must be established
Below shows an example of a Levee sloping downward to the Northeast. If you would like tilt calculations directly related to that downward sloping face, set the Structure Azimuth to 45° and the Transverse/Longitudinal Axis will shift to match. Now, movement in the Transverse+ direction will directly represent movement down the slope of the Levee.
Manufacturer Specific Azimuths
Keep in mind that azimuths are not standardized across all manufacturers. This can be seen when comparing Geokon's and Measurand's standards.