Functionality of the ADMA Standstill detection

The following describes standstill detection thresholds and their correct entry, which will increase the data integrity. Standstill allows a special form of augmentation for use with the Kalman filter, the so called Zero-Velocity-Update. This mode of the Kalman filter update increases the stability of the measurement mode in case of standstill.

If the standstill is detected (Standstill bit = 1), the INS YAW and the INS Velocity are bounded. A control-loop will only be allowed again after leaving this mode.

This constraint is determined by three independent values: Rate, Velocity and GNSS Mode.

GNSS mode as indicator for standstill

As soon as a RTK2 solution is available, the standstill is determined by observing position updates. If the RTK2 information is not available or is omitted, the standstill is determined by the two configurable parameters max rate and max velocity.

Max. rate for standstill detection

The measured ADMA rates allow a good detection of vehicle standstill, since the measured rates of the vehicle are smaller in standstill compared to those in dynamic operation. However, the thresholds have to be checked and adapted, depending on the type of vehicle. This can be done by an automatic determination via web interface (function “Auto determine Max. rate”) or with a data recording and analyzing the rate signals in standstill.

Typical threshold values for standstill detection in passenger cars are:

Max. velocity for standstill detection

If the ADMA is operated in a non-solo mode (Ext. Velocity or RTK) an additional check against the (inertial) velocity is performed for standstill detection. In that case both criteria (rate and velocity) need to be validated for the ADMA to indicate standstill detection.

Typical threshold values for standstill detection in passenger cars are: