The design of robot dedicated to person with disabilities necessitates users implication in all steps of product development: design solution, prototyping the system, choice of users interfaces, and testing it with users in real conditions. However, before any design of any system, it is necessary to understand and meet the needs of the disabled users. In this chapter, we describe our research activity on the integration of a robotic arm in the environment of disabled people who have lost the abilities to use their proper arms to perform daily living tasks and who are able to use an adapted robot to compensate, even partly, the problems of manipulation in their environments. To develop a human friendly interface it is necessary to act on the system itself to make it more flexible and easy to use. Improvement of assistive robot's functionalities must comply with users environment which is composed of several assistive aids complementary to the robot. To meet this target we should have a consistent knowledge on users' needs and taking into account their specific types of disability, their restricted possibilities, and also their acceptation level of technologies. This requires multidisciplinary competencies on several research areas, such as computer sciences, networking, robotics, home automation, and also on ergonomic to provide standardized functionalities which allow efficient usability of assistive technological aids. This chapter describes the adaptation software architecture developed for an assistive robotic arm, called Manus manipulator, in the context of smart homes where the robot is considered as an object among the others.