31-01-2013, 02:25 PM
Light Following Robot
[attachment=49080]
Introduction:
The light following robot is a mobile machine which is capable of detecting and following the light source on the traveling path. It is developed without the help of a micro-controller for providing easier connections and understanding of the circuit. It requires fewer numbers of electronic components and very cost-effective as well.
The concept of this light following robot is very simple. It includes two photodiodes, one on the right and other on the left. When the light falls on the right photodiode, the robot will move on the right side. Similarly, the robot will move on the left side when the light falls on the left photodiode.
Components used:
• Battery: One 9V battery will be sufficient for powering the robot. For more usages, two pairs of 9V battery may be required.
• Battery holder: It is used to connect the battery with the circuit.
• Breadboard: One breadboard is used for designing the circuit. The electronic components are connected by inserting it in the holes of the breadboard.
• Capacitor: Two 10uf capacitors are implemented to store the current, equalize the power output, filter, and so on.
• Castor Wheel: One castor wheel is mounted in front of the hard board for providing easy and comfortable moving of the robot.
• Gear Motor: Two 300rpm gear motors are connected with the wheel for moving the robot.
Construction and Working Principle:
Connect a 9V battery to the breadboard with the help of a battery holder. The positive power supply is passed to the IN of IC 7805 (1), and sent out through the OUT (3). The negative power supply is sent to the GND (2) connection of IC 7805. In between, two capacitors (C1 & C2) are connected to the IN and OUT of IC 7805 respectively. As a result of this process, 5V of current is obtained.
Now, connect an IC LM358 in the breadboard. As it is a voltage comparator, it will predict the output from the photodiodes based on the input voltage. For instance, let us consider that the voltage at 3rd pin is more than or equal to the voltage at 2nd pin. At this time, the 1st pin of IC LM358 will be high or else it will stay low. A 10K resistor is coupled with each photodiodes. Then, place an IC L293D in the breadboard, and join the 2nd and 15th pin of it with 1st pin of IC LM358. In between this connection, include a LED with the 10K resistor.
The BRAM-AXE Chassis Assembly
The BRAM-AXE main chassis is made from the CD/DVD which you could find easily at home or just use the blank one as I did if you don’t have any discarding CD/DVD at home. For the wheel you could use any toy’s wheel or you could use anything that has a circle form as long as the diameter is greater or equal to the servo’s arms.
The assembly of BRAM-AXE chassis is straight forward; you just need to drill two holes for placing the caster. Attached the two continues servo on the button of the CD/DVD with the double tapes and attached the wheel to the servo’s arms with the double tape or you could use the epoxy for permanent one.
The BRAM-AXE Steering Method
The BRAM-AXE steering use the simple method called the “differential drive“; when the two servos rotate on the same direction the robot will move forward or backward, and when they rotate on different direction (counter rotation to each other) the robot will rotate to left or right.
Servo basically is a high quality geared DC motor with electronic circuit for controlling the DC motor rotation direction and position; its being used widely in model hobbyist such as car R/C model for steering and acceleration control or airplane R/C model for moving the rudder, ailerons, elevators and acceleration control. Typically there are two type of servo available on the market the first one is “standard” servo which could rotate between 120 to 180 degree and the second one is “continues” servo which could rotate 360 degree.
The BRAM-AXE Sensors
In order to make the complete photovore robot, we need to use the light sensitive sensor; the simple and cheapest one is to use a special made resistor (made from Cadmium Sulfide) called Light Dependent Resistor or LDR for short. The LDR will vary its resistance according to the light intensity fall on its surface; the bright light intensity will make its resistance decrease significantly (about 1K Ohm to 5 K Ohm) while on the completely dark its resistance will increase as high as 100 K Ohm.
[attachment=49080]
Introduction:
The light following robot is a mobile machine which is capable of detecting and following the light source on the traveling path. It is developed without the help of a micro-controller for providing easier connections and understanding of the circuit. It requires fewer numbers of electronic components and very cost-effective as well.
The concept of this light following robot is very simple. It includes two photodiodes, one on the right and other on the left. When the light falls on the right photodiode, the robot will move on the right side. Similarly, the robot will move on the left side when the light falls on the left photodiode.
Components used:
• Battery: One 9V battery will be sufficient for powering the robot. For more usages, two pairs of 9V battery may be required.
• Battery holder: It is used to connect the battery with the circuit.
• Breadboard: One breadboard is used for designing the circuit. The electronic components are connected by inserting it in the holes of the breadboard.
• Capacitor: Two 10uf capacitors are implemented to store the current, equalize the power output, filter, and so on.
• Castor Wheel: One castor wheel is mounted in front of the hard board for providing easy and comfortable moving of the robot.
• Gear Motor: Two 300rpm gear motors are connected with the wheel for moving the robot.
Construction and Working Principle:
Connect a 9V battery to the breadboard with the help of a battery holder. The positive power supply is passed to the IN of IC 7805 (1), and sent out through the OUT (3). The negative power supply is sent to the GND (2) connection of IC 7805. In between, two capacitors (C1 & C2) are connected to the IN and OUT of IC 7805 respectively. As a result of this process, 5V of current is obtained.
Now, connect an IC LM358 in the breadboard. As it is a voltage comparator, it will predict the output from the photodiodes based on the input voltage. For instance, let us consider that the voltage at 3rd pin is more than or equal to the voltage at 2nd pin. At this time, the 1st pin of IC LM358 will be high or else it will stay low. A 10K resistor is coupled with each photodiodes. Then, place an IC L293D in the breadboard, and join the 2nd and 15th pin of it with 1st pin of IC LM358. In between this connection, include a LED with the 10K resistor.
The BRAM-AXE Chassis Assembly
The BRAM-AXE main chassis is made from the CD/DVD which you could find easily at home or just use the blank one as I did if you don’t have any discarding CD/DVD at home. For the wheel you could use any toy’s wheel or you could use anything that has a circle form as long as the diameter is greater or equal to the servo’s arms.
The assembly of BRAM-AXE chassis is straight forward; you just need to drill two holes for placing the caster. Attached the two continues servo on the button of the CD/DVD with the double tapes and attached the wheel to the servo’s arms with the double tape or you could use the epoxy for permanent one.
The BRAM-AXE Steering Method
The BRAM-AXE steering use the simple method called the “differential drive“; when the two servos rotate on the same direction the robot will move forward or backward, and when they rotate on different direction (counter rotation to each other) the robot will rotate to left or right.
Servo basically is a high quality geared DC motor with electronic circuit for controlling the DC motor rotation direction and position; its being used widely in model hobbyist such as car R/C model for steering and acceleration control or airplane R/C model for moving the rudder, ailerons, elevators and acceleration control. Typically there are two type of servo available on the market the first one is “standard” servo which could rotate between 120 to 180 degree and the second one is “continues” servo which could rotate 360 degree.
The BRAM-AXE Sensors
In order to make the complete photovore robot, we need to use the light sensitive sensor; the simple and cheapest one is to use a special made resistor (made from Cadmium Sulfide) called Light Dependent Resistor or LDR for short. The LDR will vary its resistance according to the light intensity fall on its surface; the bright light intensity will make its resistance decrease significantly (about 1K Ohm to 5 K Ohm) while on the completely dark its resistance will increase as high as 100 K Ohm.