AGV Anti-Collision Emergency Stop Safety System
📋 Key Summary
AGVs operate on factory floors where people work alongside them. A collision with a person is an accident — no exceptions. That's why AGV safety is a non-negotiable baseline, not an option. The defense-in-depth approach combines LiDAR anti-collision, safety bumpers, emergency stops, and area protection. This article explains how to build a reliable AGV anti-collision and emergency-stop safety architecture, and how to maintain safety in human-robot coexistence scenarios.
📌 Core Logic
An AGV hitting a person is an accident — safety is the hard baseline.
Anti-collision + emergency stop + area protection: layered defense is the only way to stay safe.
AGVs move through factories where people are constantly nearby. An AGV has no eyes and no intuition — if it hits a person, that's an accident. AGV safety is therefore a hard baseline, not an optional extra.
How is that baseline maintained? Through layered defense — LiDAR anti-collision, safety bumpers, emergency stops, and area protection. One layer is never enough; stack multiple layers.
Below, we break down how to build a dependable AGV anti-collision and emergency-stop safety system.
Three-Layer Anti-Collision: LiDAR, Bumpers, Ultrasonic
AGV anti-collision relies on three layers of protection.
LiDAR anti-collision uses forward-mounted LiDAR to scan for obstacles. When a person or object is detected ahead, the AGV decelerates and stops. With a typical detection range of 3 meters, LiDAR serves as the first line of defense, offering the longest detection distance.
Safety bumpers are contact-type sensors around the AGV's perimeter. When the AGV makes contact with a person or object, the bumper is compressed and triggers an immediate stop. This is the final physical barrier — stop on contact.
Ultrasonic obstacle avoidance covers close-range detection, filling the blind spots inherent to LiDAR scanning. Ultrasonic sensors pick up obstacles at short range that LiDAR might miss.
With all three layers working together, AGV anti-collision becomes dependable. GB/T 28264-2017 Safety Monitoring and Management System for Lifting Appliances requires safety status recording.
As the technical manager at Kelude puts it: "An AGV's safety baseline depends on layered defense — anti-collision, emergency stop, and area protection. If one layer isn't enough, add more. Every extra dollar spent on safety is one less accident waiting to happen."
Emergency Stop: Immediate Halt in an Emergency
The emergency stop is an AGV's last line of defense.
Manual emergency stop is triggered by the Emergency Stop Button on the AGV. When a person spots danger, they press the button and the AGV cuts power and stops immediately. Emergency stop response time is controlled within 0.1 seconds, and the total time from obstacle detection to full stop does not exceed 2 seconds. The Emergency Stop Button must be highly visible and easy to reach so that it can be activated instantly in an emergency situation.
Automatic emergency stop is triggered when the AGV's safety system detects a hazard. If LiDAR detects an obstacle or a safety bumper is activated, the AGV stops automatically.
Both manual and automatic emergency stop functions are essential for an immediate halt in any emergency. Kelude equips its AGVs with both manual and automatic emergency stop — dual insurance.
Area Protection & Human-Robot Coexistence: Maintaining Safe Distances
AGV safety also extends to area management and human-robot coexistence.
Area protection separates the AGV's danger zone from human activity areas. The AGV's travel path is isolated with guardrails and light curtains, preventing people from wandering in and minimizing human-robot contact opportunities.
Human-robot coexistence addresses safety when people and AGVs share the same workspace. People must be able to step aside safely as an AGV approaches, and the AGV must detect people and decelerate or stop accordingly.
When Kelude designs AGV safety solutions, the first step is area protection to isolate the danger zone, followed by safety measures for human-robot coexistence. FEM 1.001 Crane Design Standard sets requirements for operational safety.
Safety Levels: Property Class and Redundancy
An AGV's safety system must be designed to a defined safety level.
Property class indicates the safety level a system can achieve, denoted as PL. The higher the safety level of an AGV's anti-collision and emergency stop functions, the more reliable the system.
Redundancy means building redundancy into safety-critical functions. Emergency stop and anti-collision functions should use dual-channel redundancy — if one channel fails, the other keeps working.
Kelude determines the required safety level based on the AGV's operational risk, and builds redundancy into safety-critical functions to keep the safetyprotection layer reliable.
Most Common Mistakes in AGV Safety Protection
Mistake one: anti-collision without emergency stop. If anti-collision fails and there's no emergency stop as a backup, the AGV only stops after impact. Both anti-collision and emergency stop are mandatory.
Mistake two: hard-to-reach Emergency Stop Button. If the button is poorly positioned or unclearly marked, it can't be pressed in time during an emergency. The Emergency Stop Button must be prominent and easily accessible.
Mistake three: skipping area protection. When AGVs and people operate in the same space with no separation, relying solely on the AGV's own anti-collision is high-risk. Kelude prioritizes area isolation first to reduce human-robot contact.
AGV Safety Element Comparison
| element | function | characteristic | level |
|---|---|---|---|
| LiDAR anti-collision | long-range detectionDeceleration | long-range detectiondistancelong-range | primary |
| safety bumper | contact-stop | physical backup | final safeguard |
| Emergency stop | emergency stop | Manualautomatic redundancy | physical backup |
| area protection | isolationdanger zone | guardraillight curtain | pre-positioned |
AGV Safety: Quick Reference of Standard Clauses
| Standard | key provisions | safety relevance |
|---|---|---|
| GB/T 28264 Safety Monitoring and Management System-2017 | safety status recording | safety recordsrequirements |
| FEM 1.001 Crane Design Standard-2008 | operational safety requirements | operational safetybaseline |
| TSG (Special Equipment Safety Technical Regulation) 51 Safety Technical Specification for Special Equipment-2023 Crane Safety Technical Supervision Regulation | safety technical regulations | safety protection requirements |
AGV Safety FAQ: Collision Avoidance, Emergency Stops & More
Q: What protects an AGV from collisions?
A: A three-layer defense system. LiDAR detects obstacles at a distance and triggers deceleration, ultrasonic sensors cover the close-range blind spots, and safety bumpers bring the vehicle to an immediate stop on contact. Working together from far to near, this layered approach ensures the AGV cannot collide. All three layers are essential—removing any one of them leaves a critical gap in your safety net.
Q: Why is an emergency stop non-negotiable?
A: Because primary safety systems can fail. LiDAR and safety bumpers may not catch every scenario, making the emergency stop the ultimate fail-safe—whether triggered by a person spotting a hazard or activated automatically by the safety system, it halts the AGV instantly. Collision avoidance and emergency stops are two independent lines of defense; you cannot rely on just one.
Q: How is safety ensured for human-robot coexistence?
A: The approach combines area segregation with coexistence protocols. Danger zones where AGVs operate are isolated with guardrails and light curtains to prevent unauthorized access. In shared spaces, AGVs must reliably detect people, decelerate, and stop, while workers need clear paths for safe avoidance. The core principle is minimizing interaction through physical guards and maintaining a safe distance at all times.
Q: How is an AGV's safety level determined?
A: It's based on the operational risk and potential severity of injury. AGVs with higher load capacities, faster speeds, or frequent interaction with personnel require a higher safety level, often mandating redundant collision avoidance and emergency stop systems. Kelude classifies safety levels according to risk: heavy-duty AGVs and those operating in high-traffic areas use a higher grade, with safety functions built on dual-channel redundancy—if one channel fails, the other ensures the vehicle stops safely.
AGV safety shares core principles with overhead crane anti-collision systems. For a detailed comparison, see our guide on overhead crane anti-collision for multiple trolleys on the same runway using LiDAR, PLC interlock, and zone limits.
Every approach demands a safety net. Kelude engineers a layered defense using LiDAR, safety bumpers, emergency stops, and area protection, ensuring AGVs operate safely throughout your facility—protecting people and maintaining a secure working environment.
