On all current VBOX units, the amount of smoothing that can be applied at source by the GPS engine to the velocity channel can be adjusted.
There are three preset levels of smoothing labelled as dynamic levels:
- High Dynamic Tests: This is the lowest level of smoothing and should be used for any Brake stops or high dynamic vehicle tests.
- Normal Dynamic Tests: This is an intermediate level of smoothing that will give a smoother velocity, for tests such as acceleration runs between two nonzero speeds.
- Low Dynamic Tests: This is the highest level of smoothing available and can be used where live velocity is required and needs to be as smooth as possible or for coastdown tests.
VBOX level filtering is a real time filter, so once the data has been generated, the effect of the smoothing cannot be reversed. You can always use post processing smoothing, which can be adjusted whilst reusing
the same piece of original data. Further smoothing can be applied in the VBOX in real time using a Kalman Filter, where available.