The experts at DLG TestService verify the accuracy of automatic steering systems using an optical reference system. A tachymeter automatically tracks a prism mounted on the rear three-point hitch and records the measurement data. The tests are carried out on the test track at the DLG Test Center in Groß-Umstadt. All system settings are configured according to the respective manufacturer specifications.
Testkriterien
As part of the test of automatic steering systems, the following measurements are carried out:
A-B drive on level ground at 8 km/h and 15 km/h
- The accuracy of straight-line driving is determined at practical speeds by driving between points A and B on a level track.
- To assess long-term behavior regarding the stored A-B reference line, the test is repeated after more than 24 hours at 8 km/h. In addition, a one-hour test with repeated A-B runs is performed to determine lateral deviations over time.
- The deviation from the reference value is calculated as the root mean square from three runs. Results are shown in error classes of 1 cm; 95% of all measurements fall within the determined 95% error class.
- The pass-to-pass error is calculated from the data of the one-hour test.
Contour driving at 5 km/h
- For contour driving along the semicircular section of the test track, a reference line is first driven manually and recorded by the steering system. Deviations are then displayed as error classes relative to this reference run.
One-hour run with fallback from RTK to GLIDE with EGNOS
- This additional test evaluates the performance of the positioning system when RTK corrections fail and the receiver, with STEADYLINE function activated, falls back to the GLIDE solution using EGNOS.
Operation and ergonomics
- Operation and ergonomics are assessed by checking manuals and help systems for completeness, clarity, and comprehensibility. This includes additional support such as quick-start guides or online help pages. Specific tests verify user guidance, for example when defining an A-B path or troubleshooting signal issues.
- System operation is also evaluated based on the steps required to teach an A-B track and activate automatic steering.
- For practical use, display readability and usability during day and night are crucial: reflections from sunlight can impair visibility during the day, while at night the terminal must neither cause glare nor fatigue.
Safety devices
- Safety requirements for automatic steering systems are essentially defined in ISO 10975. For example, driver presence must be monitored via a seat contact switch. In addition, automatic steering must deactivate itself in case of manual intervention or signal errors. The driver must be informed visually or acoustically about the deactivation.