Low Frequency Sampling in Model Predictive Path Integral Control

Sampling-based model-predictive controllers have become a powerful optimization tool for planning and control problems in various challenging environments. In this letter, we show how the default choice of uncorrelated Gaussian distributions can be improved upon with the use of a colored noise distribution. Our choice of distribution allows for the emphasis on low frequency control signals, which can result in smoother and more exploratory samples. We use this frequency-based sampling distribution with Model Predictive Path Integral (MPPI) in both hardware and simulation experiments to show better or equal performance on systems with various speeds of input response.