How to Solve the Robot "Obstacle Avoidance" Problem? 2D LiDAR and Multi-Sensor Fusion Solutions
- Share
- publisher
- Zoe
- Issue Time
- Feb 7,2025
Summary
2D LiDAR, as the core sensor for robot obstacle avoidance, provides precise data for obstacle detection while also enabling SLAM.
How to Solve the Robot "Obstacle Avoidance" Problem? 2D LiDAR and Multi-Sensor Fusion Solutions
In the field of robot navigation and autonomous movement, obstacle avoidance is a core issue. Whether it's a home robot vacuum, an industrial AGV (Automated Guided Vehicle), or a service robot, the ability to avoid obstacles directly determines the robot's intelligence level and practicality. In recent years, 2D LiDAR (2D Laser Radar) has become one of the mainstream sensors for robot obstacle avoidance due to its precise distance measurement and efficient environmental scanning capabilities.
2D LiDAR: The Core Sensor for Robot Obstacle Avoidance
2D LiDAR calculates the distance between the object and the robot by emitting laser beams and measuring the reflection time. It has the following advantages:
▪️High Precision Measurement: 2D LiDAR can provide centimeter-level distance measurement accuracy, making it suitable for most obstacle avoidance needs in flat environments.
▪️Fast Environmental Scanning: With a high scanning frequency, 2D LiDAR can generate real-time environmental maps to help robots quickly perceive nearby obstacles.
▪️Strong Adaptability: 2D LiDAR can work stably in both indoor and outdoor environments and is unaffected by lighting conditions.
Recommended 2D LiDAR LD-20D Series
▪️20m scanning range + 270° angle
▪️Automatic learning, learns from the actual scene, and monitors the profile
▪️Multi-area monitoring with independently set monitoring zones
▪️Pause function, considers production needs with built-in shutdown and restart features to match production line movement strategies
▪️External device driver provides DC 30V 50mA driving power
▪️16 zone group settings for fast configuration and loading
Limitations of 2D LiDAR and the Complementary Role of Ultrasonic Sensors
Although LiDAR performs excellently in obstacle avoidance, it also has its limitations, especially when dealing with complex three-dimensional obstacles. LiDAR mainly provides distance information on the horizontal plane, making it less effective at recognizing vertically oriented objects or irregularly shaped obstacles.
To overcome the limitations of 2D LiDAR, a multi-sensor fusion solution can be used, combining the strengths of ultrasonic sensors and depth cameras to achieve more comprehensive environmental perception.
Ultrasonic Sensors: Low-Cost, Short-Distance Obstacle Avoidance Solution
Ultrasonic sensors calculate the distance by emitting ultrasonic waves and measuring the echo time. Its advantages include:
▪️Low Cost: Ultrasonic sensors are much cheaper than LiDAR and depth cameras, making them suitable for large-scale applications.
▪️Transparent Object Detection: Ultrasonic sensors can detect transparent objects like glass and mirrors, which is difficult for 2D LiDAR to achieve.
▪️Quick Response at Close Range: Ultrasonic sensors provide high detection accuracy over short distances (typically from a few centimeters to several meters), making them ideal for robots to perform quick obstacle avoidance when close to obstacles.
Depth Cameras: The Ideal Choice for 3D Environmental Perception
Depth cameras use infrared or structured light technology to directly capture the three-dimensional information of the surrounding environment. Its advantages include:
▪️Detection of Three-Dimensional Obstacles: Depth cameras can perceive obstacles both horizontally and vertically, making them suitable for handling complex three-dimensional environments.
▪️High-Precision Obstacle Avoidance: The 3D data provided by depth cameras helps robots plan more accurate avoidance paths, especially in narrow or complex spaces.
▪️Versatility: In addition to obstacle avoidance, depth cameras can also be used for object recognition, gesture interaction, and other advanced functions.
However, depth cameras are expensive and sensitive to lighting conditions (e.g., performance may decrease in strong light or darkness). Therefore, they are generally used as a supplement to 2D LiDAR rather than a replacement.
Comparison of 2D LiDAR and 3D LiDAR: The Cost-Effective Choice
In many robotic applications, although 3D LiDAR provides more comprehensive 3D environmental perception, its high cost and complex design discourage many companies from using it. In contrast, 2D LiDAR offers more advantages:
▪️Cost-Effectiveness: Compared to 3D LiDAR, 2D LiDAR is more affordable, significantly reducing the overall system cost. Its simplified design not only reduces production costs but also makes large-scale applications possible.
▪️Simplified Design: 2D LiDAR typically scans only in the horizontal plane, allowing it to quickly acquire environmental data. For most industrial applications, horizontal scanning is sufficient to meet the robot's obstacle avoidance needs. Especially in environments without vertical obstacles, 2D LiDAR provides ample environmental perception.
▪️Wide Applications: Thanks to its simplified design, 2D LiDAR can be widely used in automated warehouses, robotic material handling, and autonomous driving, making it a cost-effective option.
Related Sensors
20m distance, A technique that uses a laser beam to measure distance and create detailed maps of objects and environments.
Sensing range 20m, A technique that uses a laser beam to measure distance and create detailed maps of objects and environments.
Detection range: 350-6000 mm
Material: copper nickel plating, plastic fittings
Connection type: 5-pin M12 connector
Output method: RS485
Output method: NPN/PNP+analog+RS485
Resolution: 1mm
Laser type: red semiconductor laser Class II laser 655+10nm<1m
Reaction time: 50-200ms
Measure distance: 0.1-50m