The Modular Electro-Acoustic Robotic Instrument System (MEARIS) represents a new type of hybrid electroacoustic-electromechanical instrument model. Monochord-Aerophone Robotic Instrument Ensemble (MARIE), the first realization of a MEARIS, is a set of interconnected monochord and cylindrical aerophone robotic musical instruments created by Expressive Machines Musical Instruments (EMMI). MARIE comprises one or more matched pairs of Automatic Monochord Instruments (AMI) and Cylindrical Aerophone Robotic Instruments (CARI). Each AMI and CARI is a self-contained, independently operable robotic instrument with an acoustic element, a control system that enables automated manipulation of this element, and an audio system that includes input and output transducers coupled to the acoustic element. Each AMI-CARI pair can also operate as an interconnected hybrid instrument, allowing for effects that have heretofore been the domain of physical modeling technologies, such as a plucked air column or blown string. Since its creation, MARIE has toured widely, performed with dozens of human instrumentalists, and has been utilized by nine composers in the realization of more than twenty new musical works.