PDR hysteresis

PDR (Pedestrian Dead Reckoning) hysteresis refers to the phenomenon where errors accumulate in the position estimation of a pedestrian using PDR based on the stride length and heading direction. This error accumulation is due to the fact that the step length and heading direction estimates are not perfect and can be affected by various factors such as walking speed, terrain, and sensor noise.

Hysteresis refers to the fact that the error accumulation is not symmetric in the forward and backward directions of movement. This is because errors in the stride length estimation can lead to a bias in the estimated position, which can cause a shift in the estimated heading direction. This shift in heading direction can cause errors in the stride length estimation in the opposite direction of movement, which leads to an asymmetric error accumulation.

To mitigate PDR hysteresis, various techniques can be used such as using multiple sensors, incorporating map information, and using machine learning algorithms to model the error accumulation.