TIRSAK in Turkish means "timid" it is an obstacle avoiding path follower (OBAPF). 4 IR sensors were used. Differential drive for wheels and a roll-on deodorant top as a castor wheel :))) It is controlled with 16F628. main purpose is : it is not crashing to obstacles and goes to target. also if it is let free in a room it doesnt crash to walls and hangs around. 4 9V were used for steps, 2 9V were used for sensors and PIC. It is costed around 100$ if we had produced our IR sensors by ourselves it would be cheaper. 2 GP2D15 sharp IR sensors 2 15 degrees Steps PIC 16F628 Email: murat.yumak@arcelik.com