They could also run the vpp on some input acceleration function or data from field measurements stored in a file on the initial time step, and then use the corrected values in the model itself, for example, with PresetAcceleration. A user could pass a nodal acceleration solution and the vpp would return the adjusted time histories. The object would be a vectorpostprocessor whose general purpose would fall into the same category as the ResponseSpectraCalculator, i.e., a signal processing function. Implementation of this capability would be in support of my graduate research for NEUP Project: 17-12939. I think it could be useful to many to have a C++ object capable of performing these corrections in MASTODON. Baseline correction is a method to transform the time history variables of a vibrating particle such that its mean position is a constant, zero-valued one, without adversely affecting the peak accelerations or spectral properties. Initial conditions are often unknown or difficult to satisfy while maintaining the expected behavior that a vibration signal oscillates about a constant baseline and comes to rest at or near the initial position. Integration of harmonic, or quasi-harmonic, acceleration or velocity time histories can result in displacements that exhibit an unrealistic deviation from a particle's initial position over time, depending on the assumed properties of the given signal.