When installing an Inertial Navigation System (INS), accurate lever arm estimation between the INS and the GNSS antennas, as well as between the INS and additional sensors such as Odometer or DVL, presents a significant challenge.
What is a lever arm?
The Lever Arm is the positional offset of the GNSS antenna or other reference points on the platform with respect to the INS reference point, usually expressed as a 3D vector (X, Y, Z).
Precise lever arm estimation is critical in GNSS/INS fusion because GNSS provides the position of the antenna, while the attitude information computed by the INS is referenced within the sensor itself, which is installed at a different location.
This offset, between the location of the antennas and the location of the INS means these points experience different dynamics during motion.
Challenges in traditional lever arm estimation
Even small errors in lever arm estimation can introduce significant positioning inaccuracies. Traditionally, this requires careful manual measurement, it comes with several challenges in practice:
- Human error: small misalignments in measurements can lead to cumulative errors in positioning calculations.
- Difficult access to mounting points: the IMU and GNSS antenna may be mounted in hard-to-reach locations, making precise measurement difficult.
- Time-consuming process: Ensuring high accuracy requires multiple checks and validations, adding extra time to the installation process.
Automated solution: Qinertia-leverArm
To simplify this process and improve both efficiency and accuracy, we are introducing Qinertia-leverArm – a free lever arm estimation tool, designed to re-estimate the lever arm automatically. It eliminates the need for careful manual measurement, allowing SBG systems’ users to install their IMU with a rough estimate and refine it later with the tool.
Key benefits
Qinertia-leverArm offers several advantages that make it a game-changing solution for lever arm estimation. Here are the main advantages that make this solution stand out:
- Free and accessible: available to all users with a MySBG account, no additional cost.
- Compatible with all SBG products.
- No manual precision required: start with an approximate measurement and let the Qinertia-leverArm refine it.
- Improved positioning accuracy with minimal effort: use PPK data to dynamically estimate the lever arm.
- With Qinertia-leverArm, users can ensure more accurate lever arm values, leading to improved positioning without the hassle of manual adjustments.
Watch the video below for a complete walkthrough.
Get Started with Qinertia-leverArm
Ready to try our lever arm estimation tool yourself? Download the latest version of Qinertia under the “Download “section of your MySBG account. Once installed, simply log in with your MySBG account when starting Qinertia lever-Arm tool.
If you don’t have a MySBG account yet, just visit my.sbg-systems.com to register and get started!
