This paper proposes, for the purpose of offsetting the limited capability of the heterogeneous sensors stationed in the environment to collect the user information, the active information supplement framework. In this framework, the communication robots used for offering services to users are utilized as new sensors to actively collect user information by interacting with the user; the information acquired by the communication robots are used to complete the information obtained by the heterogeneous sensors. The feature of the framework is its systematic execution of the sensor fusion and the supplement function; it treats the actual robots and sensors as 4W robots and 4W sensors in a uniform manner. We also implement a network robot platform on the framework and describe the experiment conducted to confirm the basic function of the framework.