This model simulates a five cylinder radial engine. The pressure dynamics inside the cylinders are modelled using the Simscape™ Gas library. The 3D mechanical components are modelled using Simscape Multibody™. See inside any of the blocks called "Force Model" to see how the 1D and 3D mechanical parts of the model are interfaced. The pressure model is an ideal pressure source which applies pressure based on the crank angle. This model can be replaced with a more realistic pressure model of the cylinder chamber. The cylinders fire in the sequence - A C E B D providing a power stroke every 144 deg of crank rotation.