LiDAR (Light Detection and Ranging)
What is LiDAR (Light Detection and Ranging) in Humanoid Robotics?
A sensing method that uses laser pulses to measure distances and create 3D maps of the environment.
LiDAR enables robots to build detailed spatial maps, detect obstacles, and navigate complex environments with high precision, even in low light.
How LiDAR (Light Detection and Ranging) Works
LiDAR systems emit laser pulses (often thousands per second) in different directions using rotating mirrors or solid-state beam steering. When a pulse hits an object, some light reflects back to the sensor. By measuring the time delay between emission and return (time-of-flight), the system calculates distance using the speed of light. Combining distance measurements with the known emission angles creates a 3D point cloud - millions of points representing the environment's geometry. Processing software filters noise, identifies surfaces, and detects objects. Some LiDAR systems use frequency modulation or phase shift instead of time-of-flight. The resulting 3D map updates in real-time as the robot moves.
Types of LiDAR (Light Detection and Ranging)
- Mechanical LiDAR: Rotating mirror or entire sensor assembly, 360° coverage
- Solid-State LiDAR: No moving parts, more reliable, narrower field of view
- Time-of-Flight: Measures round-trip time, most common
- FMCW (Frequency Modulated Continuous Wave): Also measures velocity, emerging technology. 2D LiDAR: Single scanning plane, used for ground-level obstacle detection. 3D LiDAR: Multiple scan planes or full 3D coverage
