When deploying AGVs/AMRs in a factory, "which navigation type should I choose" is usually the first question asked - and the easiest one to get wrong. Many assume only three options exist: magnetic tape, QR code, and SLAM. In reality, industrial environments also use reflector-based laser, inductive wire guidance, and visual V-SLAM - each with vastly different precision, flexibility, and cost profiles. This article compares seven mainstream navigation technologies using structured comparison tables and a decision tree.

I. Marker-Based Navigation - Comparison

Dependent on physical ground markers. High precision, limited flexibility.

II. Self-Localizing Navigation - Comparison

No ground markers required. AGV autonomously perceives environment. Flexibility is the key advantage.

III. Auxiliary / Special-Scenario Solutions

IV. FAQ: 15 Navigation Selection Questions

Q1: What are all the AGV navigation types? What's the core difference?

Two broad categories - Mark-based (magnetic tape, inductive wire, QR code, reflector laser) rely on physical markers with high precision but limited flexibility; Self-localizing (laser SLAM, visual SLAM) use sensor-based mapping without any markers, offering maximum flexibility. Auxiliary solutions (IMU, UWB, GPS/RTK) are typically not used standalone. The essence of selection is balancing precision, flexibility, and deployment cost.

Q2: When should I use magnetic tape navigation?

Long-term fixed routes, high-volume transport, budget-sensitive production lines. Example: fixed loops from raw-material warehouse to production line. If the layout won't change for 3 years, magnetic tape offers the best cost-performance ratio. Be aware: tape wears and is sensitive to metal debris.

Q3: How is inductive wire different from magnetic tape?

Inductive wire is the predecessor - floor-grooved wire carrying current creates a magnetic field. Advantage: no surface contaminants (suitable for cleanrooms / food production). Disadvantage: groove damages floor, route changes nearly impossible. Magnetic tape is the "lightweight" surface-applied version - faster deployment, lower cost.

Q4: When should I use QR code navigation?

When you need high-precision docking (±5 mm) at relatively fixed positions. Examples: lifting AGV precision docking at workstation buffer zones, warehouse sorting interfaces. QR codes provide the highest precision of all types; tags are cheap and re-tagging is easy.

Q5: What is reflector laser navigation? How is it different from laser SLAM?

Reflector navigation requires laser reflectors mounted on walls/columns. The AGV emits laser beams, captures reflected signals, and triangulates position. It is the most mature industrial high-precision solution with ±5~10 mm accuracy. Key difference from laser SLAM: reflectors are fixed markers requiring recalibration for route changes; SLAM needs no markers - just update the map.

Q6: When should I use laser SLAM natural navigation?

Variable routes, frequent line reconfiguration, cross-zone free movement. Examples: mixed-model assembly lines, cross-workshop transport, 3C flexible production. The most flexible solution - route changes require only a map update. Prerequisite: stable environmental features (large reflective/glass areas degrade performance).

Q7: What is Visual SLAM (V-SLAM)? How do I choose vs. Laser SLAM?

V-SLAM uses cameras/depth cameras instead of LiDAR for mapping and localization. Sensors are cheap (low hundreds vs. thousands), and visual data is rich (color, texture, semantics). Weakness: lighting-dependent; less stable than laser in dynamic environments. Selection guide: stable lighting + cost-sensitive → V-SLAM; industrial environment + precision-first → Laser SLAM.

Q8: What navigation for a flexible multi-model production line?

Recommended: Laser SLAM as the backbone + QR code or reflector laser for precision docking. SLAM handles flexible trunk logistics; QR or reflectors handle high-precision workstation docking. This is the most proven architecture for automotive assembly and 3C flexible lines.

Q9: Can multiple navigation types be fused? How?

Yes, and increasingly mainstream. Common combinations: SLAM free navigation + QR/reflector precision docking, or SLAM indoor + GPS/RTK outdoor for campus-level connectivity. Skybridge's dispatch system supports multi-navigation AGV unified task orchestration, eliminating system fragmentation.

Q10: How do all seven types rank in positioning precision?

QR Code (±5 mm) ≈ Inductive Wire (±5~10 mm) > Reflector Laser (±5~10 mm) > Magnetic Tape (±10 mm) > Laser SLAM (±10~20 mm) > Visual SLAM (±10~30 mm). Note: Precision is also affected by chassis control, docking mechanisms, and floor flatness - not navigation alone.

Q11: How do I estimate deployment time and cost?

Fastest: Magnetic tape / QR code (days to 2 weeks, mainly surface installation). Medium: Reflector laser / Visual SLAM (1~3 weeks for calibration/mapping). Longer: Laser SLAM (2~4 weeks including mapping + path planning, but saves construction). Heaviest: Inductive wire (several weeks, includes civil works).

Q12: Can inertial navigation (IMU + odometer) work standalone?

No. IMU position estimation through acceleration integration has error that accumulates rapidly (drift). It must be paired with another absolute positioning method (magnetic tape / QR code / SLAM) for periodic correction. Its value: providing smooth short-range motion estimates between absolute positioning fixes.

Q13: Can RFID / UWB / Bluetooth be used for AGV navigation?

They can serve as zone-level positioning aids, but not for independent navigation. RFID triggers location confirmation at path keypoints; UWB provides indoor zone positioning (±30 cm); Bluetooth acts as proximity beacon. All three are low-cost and fast to deploy - suitable for warehouse zone management.

Q14: What navigation for outdoor inter-facility AGV logistics?

GPS/RTK differential positioning (up to ±2 cm precision) + laser SLAM for seamless indoor handoff. RTK requires a reference station or differential service subscription. Note: outdoor-to-indoor transition zones require IMU + SLAM takeover - standalone GPS cannot handle building entrance occlusion.

Q15: Is there a simple selection decision tree?

Yes - use the four-question decision tree in Section V below to lock in your recommendation in 30 seconds.

V. One-Page Decision Tree

VI. Further Reading

• AGV Transforms SPS Material Delivery in Automotive Assembly Lines (Skybridge in-depth case study with SLAM + QR code fusion practice)
• Skybridge Robot AGV Products & Industry Solutions (skbrobot.com)