Introduction to Key Sensors for Vehicle Positioning
In autonomous vehicles (AVs), accurate localization is crucial for safe navigation. Initial positioning relies on a combination of sensors: GPS (Global Positioning System), IMU (Inertial Measurement Unit), and wheel odometry. These provide complementary data to estimate the vehicle's pose (position and orientation) in the environment.
- GPS: Uses satellite signals to determine global coordinates. It provides absolute positioning with accuracy around 1-5 meters in open areas, but suffers from signal loss in urban canyons or indoors.
- IMU: Measures acceleration and angular velocity using accelerometers and gyroscopes. It excels in short-term, high-frequency updates but drifts over time due to integration errors.
- Wheel Odometry: Tracks vehicle motion by monitoring wheel rotations and steering angles. It's relative positioning, starting from an initial pose, and accumulates errors from wheel slip or uneven terrain.
These sensors form the foundation for dead reckoning and fusion techniques in the localization pipeline.