MLS Line Guidance – Interference Field Suppression and TPDO1 Mode Selection

1. Introduction

In practical AGV and AGC applications, external magnetic influences can affect the performance of a magnetic line guidance system. Typical sources of interference include:
- magnetized steel reinforcement in concrete floors
- ferromagnetic vehicle components
- large metallic or magnetic structures in the environment

In addition, flush-mounted diverter place high demands on line center point detection because multiple tracks are very close to each other. To address these challenges, the MLS provides several TPDO1 modes with configurable interference field suppression and enhanced switch detection.

2. Basic Concepts

Track data format:
- Standard: Output of line center points (LCP) without track width information
- Combi: Combined output of line center point and track width within one data word

Interference field suppression (compensated):
- Suppresses large-area, slowly varying magnetic fields

Enhanced switch detection (enhanced):
- Uses additional track width information to ensure smooth and stable detection of flush-mounted diverter

3. TPDO1 Mode Overview

The TPDO1 mode is configured via Index 0x2006, Subindex 1. The following settings are available:

0 – Standard: Standard track data, no interference field suppression, no enhanced switch detection. Recommended for simple environments.

1 – Combi: Combi track data, no interference field suppression. Use when track width information is required in clean environments.

2 – Standard compensated: Standard track data with interference field suppression. Use when magnetic interference is present.

3 – Standard enhanced: Standard track data with enhanced switch detection. Recommended for flush-mounted diverter.

4 – Standard enhanced compensated: Standard track data with interference field suppression and enhanced diverter detection. Preferred default for many AGV applications.

5 – Combi compensated: Combi track data with interference field suppression. Track width required and interference present.

6 – Combi enhanced: Combi track data with enhanced switch detection. Flush-mounted diverter and track width required.

7 – Combi enhanced compensated: Combi track data with interference field suppression and enhanced diverter detection. For demanding applications.

4. Decision Guide – Which Mode to Use?

General rules:
- Magnetic interference present → use compensated modes
- Flush-mounted diverter used → use enhanced modes
- Track width required → use Combi modes

Example:
An AGV operates on a reinforced concrete floor with flush-mounted diverter. Track width information is not required.
Recommended setting: Value 4 – Standard enhanced compensated.

5. Practical Notes

• - A device restart is required after changing the TPDO1 mode.
  ​- Interference field suppression requires sufficient magnetic field gradient of the magnetic tape.
  ​- Very weak magnetic tapes may reduce detection reliability when suppression is active.
  ​- Offset calibration is recommended before commissioning in disturbed environments.

6. Summary

Selecting the correct TPDO1 mode is essential for robust MLS line guidance. By combining the appropriate track data format with interference field suppression and enhanced switch detection, the MLS can be optimally adapted to a wide range of AGV and AGC applications.