US Patent 7703441 Method and device for ascertaining a cylinder pressure feature

A method for determining one or more cylinder pressure features for setting the combustion position in an internal combustion engine includes ascertaining a curve of a cylinder pressure or a curve of a cylinder pressure gradient with respect to a crankshaft angle, filtering the curve of the cylinder pressure or the curve of the cylinder pressure gradient using a filter, in order to eliminate a component of a pressure fluctuation brought about by the piston movement in the combustion chamber, and determining at least one cylinder pressure feature from the filtered curve.