A nutating disc engine (also sometimes called a disc engine) is an internal combustion engine comprising fundamentally of one moving part and a direct drive onto the crankshaft. Initially patented in 1993, it differs from earlier internal combustion engines in a number of ways and uses a circular rocking or wobbling nutating motion, drawing heavily from similar steam-powered engines developed in the 19th century, and similar to the motion of the non-rotating portion of a swash plate on a swash plate engine.