Attitude - Pitch/Roll/Yaw

Attitude provides information about an object's orientation with respect to the local level frame (horizontal plane) and true north. GNSS attitude solutions typically consist of three components: roll, pitch and yaw.

The easiest way to understand what we mean by attitude is to consider a plane with three linear axis running through it:

  • Wing up/down = Roll
  • Nose up/down = Pitch
  • Nose left/right = heading/yaw/azimuth

Angular measurement on the horizontal plane, with respect to true north, is referred to as yaw. Yaw is also known as azimuth or heading. The angular measurement on the vertical plane, with respect to the local level frame, is computed as pitch or roll.

Attitude measurements are important for precise positioning in many applications including:

Mobile Mapping

  • Photogrammetry or scanning

Airborne Reconnaissance

  • Pointing of cameras to a specific location on the ground

Helicopter navigation

  • Where the nose is pointing, not how the helicopter is tracking over ground

Motion compensation applications

  • Ensure airborne mapping camera points vertically to the ground
  • Ensure marine mapping is not distorted by wave movement


  • Real time and post-mission processed attitude solutions
  • GPS/GNSS standalone systems and GNSS/INS systems available
  • User customizable output orientation frame
  • Output available in different formats

What We Offer


Real Time GPS or GNSS Attitude Determination:

  • Two GNSS antennas will generate a vector in space that has both horizontal (azimuth) and vertical (pitch or roll) components
  • Heading and pitch/roll between the antennas are computed using our ALIGN® heading engine
  • ALIGN heading accuracy is a function of the horizontal separation between the two antennas
  • A full attitude (roll, pitch and yaw) solution is possible but requires a minimum of three antennas mounted on the object in an orthogonal triad formation:

Real Time GPS/INS or GNSS/INS Attitude Determination:

  • An Inertial Measurement Unit (IMU) measures angular rate of change, and yields a full six degrees-of-freedom attitude solution
  • Attitude accuracy of our SPAN® GPS/INS or GNSS/INS systems is based on the accelerometer and gyroscope specification of the IMU being used
  • Attitude is measured relative to the IMU frame. Output can be configured based on the object's orientation frame instead of the IMU frame
  • A SPAN system typically consists of one antenna, one GNSS receiver and one IMU. Dual antenna SPAN systems are also available to enhance initialization time and long term stability of the system

Post-processed Attitude Solutions:

  • Inertial Explorer® post-processing software takes advantage of both forward and backward data computations to generate the most accurate combined solution. This is especially useful for increasing solution accuracy and availability and providing quality assessment of data collected under challenging environments
  • A GNSS receiver raw code and phase data plus IMU raw measurements can be post-processed to obtain roll, pitch and yaw measurements. The forward post-processed solution will be similar to the real time SPAN attitude system mentioned above

Things to Think About


When choosing an attitude solution, consider the following needs of your application:

  • Solution accuracy
  • Signal availability
  • Solution rate
  • Continuity of solution updates
  • System alignment constraints
  • Type of motion
  • System exportability
  • System price
  • System installation constraints
  • Real-time versus post-processed solution


SPAN® GNSS Inertial Navigation Systems

Combining GNSS receiver technology with Inertial Navigation Systems (INS) provides a superior positioning solution with 3D position, attitude (roll, pitch, yaw) and velocity. Used with commercial cards or with SAASM.


Provides high precision attitude and accurate relative positioning information between two or more receivers in dynamic land, air and marine applications

Inertial Explorer®

Expands on the powerful features of GrafNav by adding support for loosely coupled and tightly coupled GNSS+INS processing