This document discusses developing intelligent controllers for HVAC systems. It proposes using disturbance observers to estimate disturbances in real-time and compensate for them to minimize energy use while maintaining comfort. An iterative learning controller is also proposed to minimize noise from the HVAC system by adapting to changing conditions. Advanced periodic controllers using a disturbance observer technique are discussed to reject periodic and non-periodic disturbances. Future efforts will focus on developing integrated sensing-controller chips using MEMS technology.