Explore a detailed physics seminar lecture examining the engineering of two-dimensional electronic flat bands formed by dumbbell-like localized states. Using the tight-binding approximation, analyze electronic band structures for several specially constructed two-dimensional lattices that ensure the presence of a dispersionless band in the spectrum. Learn sufficient rules for constructing such lattices and constraints on tight-binding model parameters that guarantee flat bands in the electronic spectrum. Focus on cases where compact localized states, which are system eigenstates corresponding to flat band energy, have a dumbbell-like character. Examine two original lattices proposed to achieve flat bands under specific conditions, and understand how analyzing electronic band arrangements based on tight-binding model parameters can be approached uniformly for both proposed lattices, the kagome dual lattice, and the diamond ladder structure.