: Line Tracer robot CONTENTS: CONTENTS OBJECTIVE WHAT IS A LINE TRACER? ITS COMPONENTS LM324 IC7805 MICROPROCESSOR BLOCK DIAGRAM WORKING ECONOMIC IMPORTANCE objective :: objective : Our object is to make a semi-autonomous robot that can follow a back lined path placed over a white background. WHAT IS A LINE TRACER? : WHAT IS A LINE TRACER? Line follower is a machine that can follow a path. The path can be visible like a black line on a white surface (or vice-versa) or it can be invisible like a magnetic field. COMPONENTS : : COMPONENTS : LEDs : Light Emitting Diode(LED) works as a transmitter to sense the color of line follower. LDR - Light Dependent Resistor It can be used to differentiate two contrast colors. PowerPoint Presentation: Resistors: Resistors are passive elements in the circuits which are used to resist the FLOW OF CURRENT . Potentiometer: They are specified by their maximum resistance. Motor drivers & Motors. LM324: LM324 IC LM324 is a comparator IC. It is a MAIN BRAIN of line tracer. The Ports takes two voltage inputs at positive and negative pin respectively, compares them and gives a digital output in the form of logicalHIGH or logical LOW. PowerPoint Presentation: GROUND: NEGATIVE TERMINAL OF BATTERY OR TO THE MIDDLE PIN OF IC 7805 5 VOLT SUPPLY PORT 1 PORT 2 PORT 3 PORT 4 Pin No. 2,6,9,13 : Negative inputs of respective ports. • Pin No. 3,5,10,12 : Positive inputs of respective ports. • Pin No. 1,7,8,14 : Outputs of respective ports IC 7805: IC 7805 It converts a positive voltage (7-29V) to +5 volts. Heat sink provided in the center to release heat generated due to drop across the IC. It may also be used to avoid the fluctuations (ripples) from the input power source and thus gives a perfect DC supply. The AVR microcontroller:: The AVR microcontroller: AVR microcontrollers is a single chip CPU, and a well-defined I/O structure that limits the need for external components. Microcontroller performs single task at once. It is used in mini component designs performing program oriented functions. Block diagram :: Block diagram : Circuit :: Circuit : WORKING:: WORKING: The robot consists of two light detecting sensors (LDR) paired with LEDs. The LEDs continuously emits light. When the robot is on white line, the light sent by LEDs is reflected back and received by LDRs, so that the robot moves forward. If a sensor come to black region then no light is reflected back to the LDR. PowerPoint Presentation: When left sensor comes in white(for black line tracer) region then right motor stops while left motor continue to move so that right turn takes place and robot returns on white line. When right sensor comes in white region then left motor stops while right motor continue to move so that left turn takes place and robot returns on white line. When both sensors are on black line then robot moves forward. The same concept helps to take a turn Motion of line tracer: Economic importance: Economic importance Practical applications of a line follower : Automated cars running on roads with embedded magnets; guidance system for industrial robots moving on shop floor etc. Sensing a line and maneuvering the robot to stay on course, while constantly correcting wrong moves using feedback mechanism forms a simple yet effective closed loop system. As a programmer you get an opportunity to ‘teach’ the robot how to follow the line thus giving it a human-like property of responding to stimuli.