What is the Drift test utility?
The drift test utility is designed to provide a quick and easy way to measure the lateral drift of vehicles.
There are controls available to determine your own lateral drift test conditions and you can see a time visualisation depicting the vehicle's drift in real-time.
Fig 1: Drift test utility window example
To access the Drift test utility, select 'Utilities' from the toolbar at the top, and select 'Drift test' from the drop-down menu.
Using the Drift test utility
Use the 'Configuration' tab to set up the test conditions, and view the data that gets collected in the tests in the 'Report' tab.
Here is some guidance on the various tools contained within the Drift test utility - See image above for reference on terms:
- Device - Firstly select the device you are using in your drift test
- Test length - Enter the length (metres by default) of the test measurement area
- Maximum drift - Enter the maximum drift (in metres) that will be measured within the test
- Speed properties - Enter the unit for measuring speed in the test (default is mph) and the dimensions (2D or 3D) speed is measured within. 2D is appropriate for vehicle lateral drift testing.
- Distance properties - Enter the unit for distance measurements in the test (default is m) and the mode within which the IMU takes its measurements - Set the mode to 'Free' in good open sky conditions, and 'Hold' when in poor GNSS conditions.
- Line file settings - You can set your own start line for your test. When the vehicle passes the start line, the test will begin. You can load a previously saved start line within the utility, or set a new one. When you choose the 'New/Edit' option, you can then set a start line according to a position obtained from the device or a map file.
- Start line directory - This is the location of the folder that contains one or more start line files
- Line file name - This is the file name of the start line file used to trigger the test
- Save test data directory - This is the folder where tests are stored
- Save test data file name - The name of the test file
- Start test on start line - The test will start when the vehicle passes the start line you've set
- Start test on trigger - The test will start each time the device reports a trigger event
- Start in key press (F8) - The test can be manually triggered each time F8 is pressed
- Number of plots to display - Defines the number of plots that will be added before the graph automatically clears. When the graph clears, the files created for the report page will remain.
The Report tab provides a more detailed summary of the drift tests that are saved automatically. Each CSV file found in the Save test Data Directory can be selected and reviewed. A Delete files button at the bottom of the report tab can be used to remove all CSV files in the working directory. Please note that you should change the default working directory to avoid accidentally deleting important files.
For detailed guidance on the complete set of NAVdisplay utilities, see pages 55-65 of the NAVdisplay user manual.