The input parameters are Sensor Address and command.
The Sensor address is written in Hexadecimal on the Sensor.

 private int read_distance(int Sensor,byte cmd)
            //byte cmd;
            byte addr_h,addr_m, addr_l;
            byte distance_h, distance_l;
            byte data=0;
            byte checksum;
            int tmp_checksum;
            int distance;
            addr_l = (byte)Sensor;
            Sensor = Sensor >> 8;
            addr_m = (byte)Sensor;
            Sensor = Sensor >> 8;
            addr_h = (byte)Sensor;
            tmp_checksum = ~(cmd + addr_h + addr_l + addr_m + data);
            checksum = (byte)tmp_checksum;
            // Break for 1ms
            serialPort1.BreakState = true;
            serialPort1.BreakState = false;
            serialPort1.Write(new byte[6] { cmd, addr_h, addr_m, addr_l, data, checksum }, 0, 6);
            if (cmd == 94) //if reading command is given
                distance_h = (byte)serialPort1.ReadByte();
                distance_l = (byte)serialPort1.ReadByte();
                distance = distance_h;
                distance = distance << 8;
                distance = distance | distance_l;
                distance = 0;
            return distance;

First the distance needs to be measured.

read_distance(4643, 81);

After a waiting time of at least 70ms the measured distance can be read from the sensors.

sens1 = read_distance(4643, 94);

Follow And Hold Distance
A Program to follow and hold distance to an obstical was implemented in Microsoft Visual C#.
This Program reads Distance information from SRF485 Ultrasonic Rangers periodicaly.
And Controlls the Robots Movement through Robax1500.

X-Box Remote Controll
vb joystick
This Program Reads the Input from A X-Box Remote Controll, and sends this input through the Serial interface to the Robax1500 Controller.
It is implemented in Microsoft Visual Basic.
Prerequisites: DirectX SDK Download

Follow A Trajectory
This Program is Following a Predefined Trajectory.
The Trajectory is defined by Speed, Steering Angle, and Period.

What was done:

Better Steering:
The used Servo motors where not powerful enough,
A new steering concept with gearbox motor was made.

New Motor Controller was purchased:
Roboteq Robax1500

This is a 2 Channel Motor controller.
1. Channel in Speed Mode for Driving Motor
2. Channel in Positioning Mode for Steering Motor

Some Optical Changes:

New Ultrasonic Sensors where added:
SRF485 Ultra Sonic Range Finder

Lindy USB to Serial Converter