Tags: led , machine , robot A line following robot is a versatile machine utilized to detect and take after the dark lines that are drawn on the white surface. As this robot is produced utilizing a breadboard, it will be exceptionally easy to build. It likewise utilizes a position input framework for going in the desired way. Furthermore, the electric signs also, RF correspondence are required for speaking with the vehicle and framework controller.
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Sunday, 23 June Automated Line Following Robot Line-following robots with pick-and-placement capabilities are commonly used in manufacturing plants. These move on a specified path to pick the components from specified locations and place them on desired locations. Basically, a line-following robot is a self-operating robot that detects and follows a line drawn on the floor.
The path to be taken is indicated by a white line on a black surface. The control system used must sense the line and manoeuvre the robot to stay on course while constantly correcting the wrong moves using feedback mechanism, thus forming a simple yet effective closed-loop system.
Circuit description Fig. It consists of mainly four parts: two sensors, two comparators, one decision-making device and two motor drivers. The robot is built using microcontroller AT89C51 used as the decision-making device , motor driver LD, operational amplifier LM comparator , phototransistor sensor and a few discrete components. In the circuit, the sensors phototransistors are used to detect the white strip on a black background. The sensor output is fed to the microcontroller, which takes the decision and gives appropriate command to motor driver LD so as to move the motor accordingly.
The sensor senses the light reflected from the surface and feeds the output to the comparator. The sensor senses the reflected light to give an output, which is fed to the comparator. The comparator compares the analogue inputs from sensors with a fixed reference voltage.
If this voltage is greater than the reference voltage the comparator outputs a low voltage, and if it is smaller the comparator generates a high voltage that acts as input for the decision-making device microcontroller. The microcontroller is programmed to make the robot move forward, turn right or turn left based on the input coming from the comparator.
The outputs of the microcontroller are fed to the motor driver. Motor driver. The current supplied by the microcontroller to drive the motor is small. Therefore a motor-driver IC is used. It provides sufficient current to drive the motor. When light falls on the phototransistor say, T1 , it goes into saturation and starts conducting. When no light falls on the phototransistor, it is cut-off. Phototransistors T1 and T2 are used for detecting the white path on the black background.
Collectors of phototransistors T1 and T2 are connected to the inverting inputs of operational amplifiers A2 and A1. The signal voltage at the inverting input of the operational amplifier is compared with the fixed reference voltage, which is formed by a potential divider circuit of 5. This reference voltage can be adjusted by changing the value of the kilo-ohm preset. When sensor T2 is above the black surface, it remains cut-off as the black surface absorbs virtually all the light falling from LED2 and no light is reflected back.
The voltage at the inverting input pin 2 of operational amplifier A1 is higher than the reference voltage at its non-inverting input pin 3 and therefore the amplifier output at pin 1 becomes zero. When sensor T2 is above the white line, the light gets reflected from the white surface to fall on phototransistor T2. Phototransistor T2 goes into saturation and conducts. The inverting input pin 2 of operational amplifier A1 goes below the reference voltage at its non-inverting input pin 3 of operational amplifier A1 and therefore output pin 1 goes high.
Similarly, comparator A2 compares the input voltage from phototransistor T1 with a fixed reference voltage.
A 12MHz crystal is used for providing the basic clock frequency. Holding RST pin high for two machine cycles while the oscillator is running resets the device. Power-on reset is derived from resistor R5 and capacitor C1. Switch S2 is used for manual reset. The microcontroller, based on the inputs from sensor T1 say, left and sensor T2 say, right , controls the motor to make the robot turn left, turn right or move forward.
Port pins P2. Three wheels can be used for this robot—one on the front and two at the rear. Front wheel can rotate in any direction as specified by the rear wheel. To make the robot turn left, the left-side motor should stop and the right-side motor should rotate in the clockwise direction. Similarly, to make the robot turn right, the right-side motor should stop and the left-side motor should rotate in clockwise direction.
For forward motion, both the motors should rotate in clockwise direction. Port pin P3. As a result, the left motor stops and the right motor rotates, to make the robot turn left. This process continues until the left sensor comes above the black background. When both the sensors are at the white surface, the robot should stop. The output of the microcontroller IC2 depends on the inputs received at its port pins P3. It is well commented for easy understanding and works as per the flow-chart shown in Fig.
7380969 Line Follower Using AT89c51
Sunday, 23 June Automated Line Following Robot Line-following robots with pick-and-placement capabilities are commonly used in manufacturing plants. These move on a specified path to pick the components from specified locations and place them on desired locations. Basically, a line-following robot is a self-operating robot that detects and follows a line drawn on the floor. The path to be taken is indicated by a white line on a black surface.
Line follower robot using microcontroller
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. Why build a line follower? 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. Practical applications of a line follower: Automated cars running on roads with embedded magnets; guidance system for industrial robots moving on shop floor etc.