The average age of the population in industrialized countries is steadily increasing. Seniors living alone are more numerous, either because they prefer to live independently, or because of a lack of space in the specialized institutions. We must find solutions allowing them to continue to stay at home comfortably and safely. Smart housings can constitute one of these solutions. One of the biggest challenges in Ambient Assisted Living (AAL) is to develop smart homes that anticipate the health needs of their inhabitants while maintaining their safety and comfort. It is therefore essential to facilitate interaction with the smart home through systems that respond naturally to voice commands, using microphones but no tactile interfaces. This thesis defines the concept of smart home and describes some interesting projects. It then explains how home assistance can take advantage of this concept thanks to sound analysis. The acceptability of a voice interface as part of the intelligent home has been studied through an experiment that showed what are the wishes, expectations and fears of older users, their families, and social workers. Audio analysis in smart homes is a still unexplored research area, the interest and the methods to analyze sound in- formation in a smart home have been studied here in an experiment which helped to highlight the challenges and technological obstacles to be removed in order to use sound information in addition to other modalities and, in the case of speech, distant speech recognition (ASR in remote recording conditions). A practical solution using several microphones is then presented. The intended purpose is to achieve a voice control system which will allow the user to control their environment not only by conventional switches and remote control devices, but also by voice. The advantage of the audio information combined with that of home automation sensors is then revealed through a multimodal analysis making it possible to locate a person in a smart home or to determine their activity. Localization is necessary, for example to determine the context in which a home automation command has been issued. The activity can be used to observe changes in the habits of a person to assist in diagnosis. Finally, the thesis presents the perspectives of research and future projects of the author. It is accompanied by the reproduction of four scientific papers published in refereed selective conferences.
