Guiding Robots Using Mobile Phone

Communication via mobile phones is becoming increasingly common among humans but next in the pipeline is communication between human and robots. This project promotes wireless connectivity which makes it hassle free affair. In this paper we propose the concept of controlling a robot by a mobile phone from a remote area. The robot supports two ways of communication as it can receive commands by a mobile phone and in other way round it can send data through cell phone to the user. This prompted us to use a PC and its serial port with RS232 protocol. The user sitting at a distant place can send sms’s to control the robot placed far away from him (even in another continent). The sms is decoded in a PC by a program which then sends command to the robot via serial port. Similarly the robot can send information about the working environment condition received from its sensors. This data is converted to proper PDU or TEXT mode as needed by the mobile phone which is forwarded to the operator by a sms. This involves a NOKIA 6020 phone and an 8051 microcontroller (AT89C52). A RF module, connected to a computer’s serial port, can operate at two frequencies, one for communicating with the robot and another for the mobile. The cell phone’s TX and RX pins are connected to the serial port by the RF module and a MAX232 IC. The RS232 protocol does not support TTL logic so a line driver such as MAX232 has to be used to convert TTL logic levels to RS232 voltage level .The phone converses with the computer by AT commands sent through the serial port. A practical implementation of this project may witness applications such as home automation and security.