The invention relates to the technical field of
rail transit train operation control and navigation positioning, and discloses a seamless integrated
positioning system and method in a complex
railway tunnel environment, and the
system employs a three-dimensional
laser radar to construct a
local environment map in real time, detects the physical shielding condition of an ultra-
wideband signal propagation path through a light tracing technology, and achieves the real-time positioning of the ultra-
wideband signal. And the non-line-of-
sight propagation state is accurately identified. And based on an identification result, the
system dynamically adjusts a measurement
noise covariance, reduces the weight of non-line-of-
sight measurement under a
factor graph optimization framework, and fuses IMU pre-integration and
LiDAR odometer data to carry out real-time
pose calculation. In addition, high-precision
satellite positioning states of the entrance and exit of the tunnel are used as double-end
boundary constraints, and global adjustment is carried out on the whole-process track of the tunnel. According to the method, the non-line-of-
sight error is effectively inhibited from the
physical level,
dead reckoning accumulated drifting is eliminated, and the positioning robustness and precision of the
train in the complex tunnel environment are improved.