A surface contour mapping is a graphical technique for representing 3D surfaces. Devices intended to carry out such functions when placed in a 3D environment scans and explores the environment, thus, mapping the scanned environment to a 3D plane yielding the surface contour plot of the surroundings. Various methods have been adopted for mapping and localization purposes. This paper aims at providing a simple prototype for obtaining such plots. The robot constructed here consists of three ultrasonic sensors which works on the principle of an ultrasonic 3D scanner in order to map the contour of surface objects. Three ultrasonic sensors along with servo motors can explore the surroundings within a range of 1800, collecting the information regarding the surrounding surface objects in the form of cylindrical coordinates. These set of real world 3D coordinates is transferred to the PC through Arduino serial port, after which the entire set of is written to a text file with the help of Processing. Matlab reads the text file consisting of all the real world coordinates, converts it to rectangular coordinates and plots it in the 3D plane to obtain scatter plot of the 3D surroundings. A process called Reconstruction converts the obtained scatter plot into surface contour map of the surface objects. This system effectively enables us to plot 3D planar surfaces. With the usage of more accurate sensors, contour plots of complex surroundings consisting of curved object surfaces can easily be obtained.

Keywords : Surface contour map, ultrasonic sensor, exploration, 3D surroundings, surface object, 3D environment, non-contact active, semi-autonomous, Arduino, Processing, Matlab, real world coordinates, cylindrical and rectangular co-ordinate system, scatter plot,