11. The speech communication method according to claim 8 , wherein, the tracking the position of the conversation partner is further based on a combination of the speech recognition result, the image recognition result, and a contact recognition result obtained by recognizing a physical contact of the conversation partner with a contact recognition unit.
8. A speech communication method for enabling a conversation with a conversation partner, said method comprising: tracking a position of the conversation partner, in a normal mode, in response to both of a speech recognition result obtained by recognizing speech of the conversation partner and a image recognition result obtained by recognizing a face of the conversation partner; and continuing the conversation with the conversation partner without tracking including behaviors relying, in the normal mode, on tracking performed by the tracking, the conversation is continued, without tracking, through the speech content of the conversation partner being recognized and matching a predicted response while the speech communication system is in a failure mode as a result of an inability to track the position of the conversation partner.