In today's era of rapid advancement in intelligent manufacturing and smart logistics, autonomous mobile robots ( Autonomous Mobile Robot, AMR ) have become the core mobility units in factories, warehouses, and distribution centers. They navigate seamlessly between shelves, loading and unloading areas, and sorting lines, significantly boosting operational efficiency—yet they also introduce a new challenge for human-machine collaboration: how to ensure the safety of both personnel and equipment in this highly dynamic, high-density environment? This article will delve into collision-avoidance safety protocols under human-machine collaboration, exploring everything from technical principles to practical implementation strategies.

1. Why is it essential to prioritize human-machine collaboration for collision prevention?
Traditional fixed machinery relies on physically isolated zones to separate human and machine activity areas, whereas the operational characteristics of AMRs dictate that they must share the same workspace with humans. When workers manually restock items, conduct inspections and maintenance, or temporarily traverse the aisles, the lack of effective safety protection mechanisms can easily lead to the risk of physical collisions. Such incidents may result in minor damage to goods or equipment downtime at best, but at worst, they could even endanger human safety. Therefore, establishing a dual-layered safeguard system—combining "proactive prevention" with "passive protection"—is essential for achieving harmonious coexistence between humans and machines.

In the past, traditional warehousing relied on forklifts plus manual labor as the primary work model.

II. A Comprehensive Analysis of Core Protective Measures
1. Physical Layer Protection: Visible Security Boundaries
✅ 360° Audio-Visual Alarm System
High-quality AMR comes standard with a multi-angle LED warning light strip, which, combined with a buzzer, creates a dual audio-visual alert system. When the device detects a person entering the preset safety distance (typically 1–2 meters), it automatically slows down and activates a high-frequency flashing red light along with an intermittent alarm sound—effectively giving the robot an "electronic fence."

✅ Flexible Anti-Collision Structural Design
Critical areas are wrapped with elastic rubber, and pressure-sensitive touch edges are installed at the ends. Any slight contact instantly triggers an emergency stop protection, minimizing impact forces to reduce injury risks for personnel. This design is especially ideal for shelf-access scenarios in narrow aisles.

2. Intelligent Sensing System: The Invisible Digital Barrier
🔄 Multi-sensor Fusion Localization
Modern AMR integrates LiDAR, millimeter-wave radar, and depth cameras, using SLAM algorithms to build environment maps with centimeter-level precision. The system can instantly identify human positions, movement trajectories, and even predict potentially hazardous paths. For instance, if it detects someone walking away from the robot ahead, it can proactively adjust its route to safely bypass them.

🔍 Dynamic Obstacle Avoidance Strategy Grading
- Level 1 Response: Slow Down and Monitor (适用于缓慢接近的静止 targets)
- Level 2 Response: Stationary on-site + audible and visual alert (targeting rapidly moving individuals)
- Level 3 Response: Emergency Brake + Reverse Evacuation (activated in extreme situations)
This tiered mechanism avoids efficiency losses caused by frequent starts and stops, while also ensuring absolute safety in emergency situations.

3. Software Protocol Layer: The Invisible Guardian of Rules
⚙️ Speed-Distance Coordinated Control
According to the ISO 3691-4 international standard, the maximum operating speed of AMRs should be directly proportional to their detection distance. For instance, when the detection distance is ≤5 meters, the speed limit should not exceed 0.5 m/s; only when the distance exceeds 10 meters can the robot resume its rated speed. This dynamic speed-control strategy provides ample buffer time for human-robot coexistence scenarios.

📡 Priority Management Rules
At complex nodes like intersections, the system prioritizes granting right-of-way to AMRs carrying heavy pallets, while simultaneously instructing pedestrians to wait for the green light. This traffic-light-like logic design effectively mitigates conflict risks when multiple entities converge.

AMR: Autonomous Mobile Robot, an intelligent robotic device designed for automated material handling tasks.

III. Practical Applications of Ergonomics
Even the best technology requires human collaboration to achieve maximum effectiveness. Here are a few key practice recommendations:

🔹 Intuitive Visual Interface
On the AMR control panel, intuitive status indicators are set up: green signifies normal operation, orange alerts that deceleration is imminent, and flashing red indicates that the device has entered safe-mode. Additionally, managers can use a mobile app to monitor the real-time operating status and historical trajectories of each device.

🔹 Customized Training System
Develop differentiated training programs tailored to different roles: Frontline operators should master the location of the emergency stop button; maintenance personnel need to be familiar with the sensor calibration process; while management will focus on risk assessment and the development of emergency response plans. Regularly conduct simulated collision drills to reinforce safety awareness across the entire workforce.

🔹 Standardization of Environmental Signage
Spray reflective strips on the bottom of shelves and along the sides of upright posts, and paint conspicuous yellow-and-black alternating guide lines on the floor. These visual aids help AMRs more accurately identify channel boundaries, while also providing clear walking directions for personnel.

IV. Clarifying Common Misconceptions
❌ Misconception 1: Having LiDAR installed is enough for safety.
Truth: A single sensor has blind spots, and rainy or snowy weather may lead to misjudgments. A mature solution should adopt a three-modal redundancy design featuring "laser + vision + ultrasonic" technologies.

❌ Misconception 2: Fully autonomous driving equals zero intervention
Fact: All AMRs retain manual override interfaces, and path confirmation is required before each task execution. Humans always remain the final line of defense in the safety loop.

Technology for good, safety first.
     Based on the hundreds of smart warehousing projects that Guangdong Xiada Rack Services has undertaken, truly efficient automation upgrades have never simply meant "replacing humans with machines"—instead, they involve reshaping the human-machine relationship through technological innovation. When we equip AMRs with the abilities to "see," "think," and "yield," we not only enhance logistics efficiency but also underscore the company's solemn commitment to the safety and well-being of its employees. In the future, as AI technology is increasingly integrated into various applications, human-machine collaboration will undoubtedly advance toward a higher level of intelligent coexistence.