IMU Trajectory Batch Processing
Important Information
Disclaimer
Thank you for purchasing YellowScan. The present document aims at giving you simple and
straight forward directions on how to run batch trajectory corrections using the POSPac batch
manager. Please read the full document before starting operation.
General Information
This document intends to provide a step-by-step training to YellowScan users who are willing to
conduct multiple LiDAR post-processing with the Batch Processor available in Applanix POSPac
MMS and UAV.
Applanix
POSPac MMS or UAV is required. POSPac is a licensed software with individual entitlement
ID handled by their Software Licence Utility (SLU).
Every new version is available on their support website: https://applanix.force.com/support/s/
This Quick User Guide assumes that the user has all relevant
licenses active and available to follow this guide.
Introduction
For the creation of the “Smoothed Best Estimate of Trajectory” (SBET) file, the application POSPac
MMS/UAV is used. For the processing of a single flight the Standard Project Explorer is an easy to
use tool and the procedures can be found in the YellowScan User Manual.
Processing multiple flights on a project with the Standard Project Explorer can be a lengthy and
repetitive process.
Applanix have created the Batch Manager for this task. This Batch Manager creates a XML file for
processing multiple trajectories (.T04) with the needed RINEX data in one go.
The user interface of the Batch Manager needs an introduction and some pointers to successfully
complete this batch process.
Some assumptions are made before starting the Batch Manager:
• Ahead of data collection, you should have your lever arms precisely measured and entered
in the IMU for easier automation.
• Go to File > Options > Import and tick ON the “Use real-time Reference to Primary GNSS
lever arm standard deviation for APX products”.
Starting the Batch Manager
As seen in the figure below, there is a tab called Batch Manager. By clicking the tab, the Batch
Manager explorer opens on the left side. Alternatively, or if the tab doesn’t show up, you can click
on Batch Manager in the Project tab.
The options for the Batch Manager are:
Creating a New Batch
For this example, we work on a project called Coulondres. This project was flown in 1 day with a
total of 3 flights. A RINEX file is available for all 3 flights.
A new screen “Batch Editor” opens that will be the main editing screen for creating the Batch
Processing file.
Batch Editor
The Batch Editor is divided in multiple sections.
Project Settings
The first section is the Project Settings. In this section, you’ll retrieve the location and name of your
batch, as well as all operations performed in the batch.
1. Batch Name: This is the name of the batch settings you saved earlier.
2. Batch Folder: Path to where all the data will be saved, including all the individual projets.
3. Project Name: For each .T04 file, define a project name for it. This will be the name of the
individual POSPac project saved, as well as the name in the Batch Summary at the bottom.
You can have different Processing Settings for each project.
4. Processing Settings: Select the operations you want to perform for each of your projects.
Typically, you want to do at least the following:
• Extract real-time POS data
• Compute post-processed data
• Format and export navigation data
• Produce a project report in PDF format (you will have to scroll down the list to see it)
Once you have these options prepared for your flight, you can start your Task Settings for this
project. You will have to do it for each flight/project to build your batch.
Tasks Settings
This Quick User Guide assumes that you’re processing for the purposes of CloudStation use only.
Extract real-time POS data
When this option is ticked ON, you will have access to the POS Data tab in the Tasks Settings area.
Browse for your flight’s .T04 to add it to the processing for data extraction. Typically, as you’re
doing 1 folder per flight, you should only have one .T04 per folder. The Last File will automatically
be filled with the same file, as it’ll be the only one in the folder.
Typically, you want to extract the entire time interval for your mission, but if you know it needs to
be trimmed, you can adjust it here.
If you used a different GNSS antenna for your system, change it in the Rover Antenna Setup.
Compute post-process data
When this option is ticked ON, you will have access to the GNSS Mode tab in the Tasks Settings
area. You will have to select which GNSS mode you want to use: Single Base, PP-RTX or Applanix
SmartBase.
When using Single Base processing, you will need to bring at least one Base File (RINEX, .T02, …) by
clicking on Add. Once added, the Coordinate Manager will open for you to enter the base
coordinates. For more information on the Coordinate Manager, please refer to the latest POSPac
User Manual. If you are using a system with APX-20, AP+30 Air or AP+50 Air, and wish to process
the trajectory from the remote IMU, check “Use Custom Settings” (1) and select IMU Context:
Remote (3) in the new Custom Settings tab (2) that’s then available.
Format and export navigation data
When this option is ticked ON, you will have access to the Export tab in the Tasks Settings area.
By default, the option to use the selected Project Template (selected in the Project Template tab)
settings is ticked ON. To create Project Templates, please refer to the POSPac User Manual.
If you do not want to use a Project Template, you can untick this option, and select where the output
file (SBET) will be saved, as well as your Mapping Frame by unticking the respective Default options.
NB: YellowScan recommends setting up a Project Template and running it.
When you are satisfied of all the settings for your flight/project, click on Add on top of the Batch
Summary area.
Batch Summary
When you Add a Project to the Batch, a summary of operations will be displayed in the Batch
Summary area. You’ll find the project name, the first POS file as well as what GNSS mode is used
and the Base Station.
Running the Batch
Once your Batch has been defined, you can validate it by pressing OK. A summary of operations
will be displayed in the Batch Manager window. Once you’ve validated all the steps, you can hit
“Run All Projects” to start processing. You can follow all the steps in the UI.
Custom XML and Command Line
POSPac’s Batch processing can be completed with many more options by editing the XML file
created as well as running it through command lines. This avoids going through the Graphic User
Interface and makes processing faster, and more customizable.
To learn more about the file format and how to create a custom XML File and running through
command line, open the index.html file, located here by default:
C:/Program Files/Applanix/POSPac MMS 8.7/Manuals/Batch Documentation/index.html
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