The security system of home and building is an important issue to human being. We develop the low cost security robot system that is widely employed in our daily life. The security robot can detect abnormal and dangerous situation and notify us thought Internet and GSM module. The structure of the security robot contains seven parts. There are security system, avoid obstacle and driver system, software development system, auto recharging system, remote supervise system, multiple interface system and others. First, we develop a low cost based security robot using aluminum flame. Then we present the remote mobile security system (RMSS) for the security robot system, and design multiple interfaces in the Wu-Feng security robot (WFSR-II). There are wireless RS232, RF interface and IR interface. The mobile robot communicate with personal computer using wireless RS232, and communicate with sensor node system using IR interface, and communicate with other robot using RF interface. The mobile robot can transmits the message to user using GSM module. Finally, we make some experimental scenario to supervise the security robot through personal computer, and it can detect fire event to transmit message to user, and avoid obstacle in state and dynamic environment. We can get adequate result for the WFSR-U robot

Autonomous mobile robot is very flexibility to move in anywhere. But it is limited on power supply. The power of the mobile robot may provide a few hours of peak usage before the recharging behavior is necessary. So auto recharging function is an important issue in the autonomous mobile robot. It is also an important task that how to detect an exact power value in the security robot. In the paper, we use four current sensors to measure the power variety and we use redundant management method to detect and diagnosis current sensor status. First we use computer simulation and implement in the personal computer using Advantech multifunction I/O card. Next, we use detection and diagnosis algorithm in the power system of the mobile robot, and get some adequate experimental results for some variety conditions. Finally, we make some experimental scenario on the auto-recharging function using the WFSR-I mobile robot.