Description of Sun Tracking Solar Panel

Components in the Circuit:

• Solar panel
• ATmega8 micro controller
• Light Dependent Resistor.
• Motor driver IC
• Stepper Motor.

Automated Sun Tracking Solar Panel Circuit Design:

The proposed system consists of ATmega8 micro controller, Solar panel, Light Dependent resistors and motor driver IC.

ATmega8 is AVR family micro controller. It is based on advanced RISC architecture. It is an 8 bit controller. It has 4KB Flash memory, 512 bytes of EEPROM and 1Kb of SRAM. It has 23 programmable pins. It supports peripheral features like two 8-bit timers, one 16 bit timer, 6 channel ADC with 10-bit resolution, programmable USART, Serial peripheral interface, 2 wire serial interface, etc.

Solar panel is connected to Stepper motor. Solar panel consists of photovoltaic cells arranged in an order. Photovoltaic cell is nothing but a solar cell. Photo resembles light and voltaic is electricity. Solar cell is made up of semiconductor material silicon. When a light ray from Sun is incident on the solar cell, some amount of energy is absorbed by this material. The absorbed energy is enough for the electrons to jump from one orbit to other inside the atom. Cells have one or more electric field that directs the electrons which creates current. By placing metal contact energy can be obtained from these cells.

Light Dependent Resistors are the resistors whose resistance values depend on intensity of the light. As the intensity of light falling on the LDR increases, resistance value decreases. In dark, LDR will have maximum resistance. LDR will output an analog value which should be converted to digital. This can be done using analog to digital converter. ATmega8 has analog to digital converter internally. It has six ADC channels from ADC0 to ADC5.The two LDRs are connected to ADC pins i.e. PC0 and PC1. ADC conversion is done using successive approximation method.

Stepper motor rotates the panel in a stepwise angle. To drive this motor a driver IC is used. Driver IC amplifies the input voltage and protects the microcontroller from back EMF. Generally, motors generate back EMF. This may damage the controller. The driver IC used is L293D. It has H bridge internally made up of transistors. This IC has 16 pins. Output pins are connected to the stepper motor pins. Input pins are connected to the controller pins as shown in circuit diagram.

By connecting a battery to the solar panel, one can store the energy generated by the solar cells and this energy can be used when required.

Sun Tracking Solar Panel

Two light dependent resistors are arranged on the edges of the solar panel. Light dependent resistors produce low resistance when light falls on them. The stepper motor connected to the panel rotates the panel in the direction of Sun. Panel is arranged in such a way that light on two LDRs is compared and panel is rotated towards LDR which have high intensity i.e. low resistance compared to other. Stepper motor rotates the panel at certain angle.

When the intensity of the light falling on right LDR is more, panel slowly moves towards right and if intensity on the left LDR is more, panel slowly moves towards left. In the noon time, Sun is ahead and intensity of light on both the panels is same. In such cases, panel is constant and there is no rotation.

Description of Sun Tracking Solar Panel

Descritption of LCD scrolling display Module

The project is discussed in two parts.

Part 1: To Create LCD module:

In part one LCD module is created using AVR controller and 16×2 alphanumeric LCD display. The controller ATMEGA16 controls the LCD. The programmed code dumped permanently to this atmega16 is controlling the LCD module. A single receiving pin (RXD -14) of ATMEGA16 is the only input of this LCD module. The data received by serial communication is displayed on the LCD module in a scrolling manner.

Part2: Interfacing the LCD module using any other microcontroller:

In part two the controller used is in our project is another AVR chip. The data send to the LCD module via serial transmission pin (TXD-15).A switch demonstrated in our project give the input to the controller.A predefined text is transmitted to the LCD module upon every press of the switch. Whatever the text sends, the data will be scrolled in the LCD module.

Circuit Diagram:

LCD Scrolling Display Module

A microcontroller is a device which has an inbuilt processor surrounded by few dedicated hardware modules. Once the microcontroller initializes them they start operating on their own. In case of an ADC it will do the sampling and digital to analog conversion all by itself and keep the converted data in its buffer so that the microcontroller can read that later. The advantage of this kind of implementation is that the microcontroller is free to do other tasks during that time and hence increase the overall efficiency. That was the case of hardware modules or peripherals inside a microcontroller which increases the processing efficiency of the built in processor. The efficiency can increase even more if the external hardware attached to the microcontroller can also does lot more tasks by their own without depending the microcontroller. The hardware may or may not contain another processor so that it can perform certain predetermined task after initialized by the microcontroller.

An example for such a device is the serial LCD scrolling display. Once the data to be displayed in scrolling manner is received from the microcontroller, it will start the operation by its own and perform the scrolling process. This project explains interfacing of LCD MODULE with any type of controller using single serial receiving pin. In this mode only one pin is used for sending data. This scrolling display mode has the advantage over the 8-bit mode as it uses only a single pin. The remaining pins of the controller are available for normal use and the valuable processing power required to scroll the data can be used for any other purpose.

 Descritption of LCD scrolling display Module

Description of Fully Automated Solar Grass Cutter

Hardware Specifications 8051 Family Microcontroller Vehicle Body Grass Cutting Blade Solar Panel Motor Driver IC DC Motors Ultrasonic Sensor Robotic Body Capacitors Resistors Voltage Regulator Crystal Led’s

Software Specifications Keil µVision IDE MC Programming Language: Embedded C

Fully Automated Solar Grass Cutter

The fully automated solar grass cutter is a fully automated grass cutting robotic vehicle powered by solar energy that also avoids obstacles and is capable of fully automated grass cutting without the need of any human interaction. The system uses 6V batteries to power the vehicle movement motors as well as the grass cutter motor. We also use a solar panel to charge the battery so that there is no need of charging it externally. The grass cutter and vehicle motors are interfaced to an 8051 family microcontroller that controls the working of all the motors. It is also interfaced to an ultrasonic sensor for object detection. The microcontroller moves the vehicle motors in forward direction in case no obstacle is detected. On obstacle detection the ultrasonic sensor monitors it and the microcontroller thus stops the grass cuter motor to avoid any damage to the object/human/animal whatever it is. Microcontroller then turns the robotic as long as it gets clear of the object and then moves the grass cutter in forward direction again.

Description of Fully Automated Solar Grass Cutter

Description of Ultrasonic Blind Walking Stick

Hardware Specifications Atmega 328 Microcontroller Ultrasonic sensor Light Sensor Buzzer RF Rx-Tx Diodes Capacitors Resistors Voltage Regulator Crystal Led’s

Software Specifications Arduino Compiler MC Programming Language: Embedded C

Ultrasonic Blind Walking Stick

Blind stick is an innovative stick designed for visually disabled people for improved navigation. We here propose an advanced blind stick that allows visually challenged people to navigate with ease using advanced technology. The blind stick is integrated with ultrasonic sensor along with light and water sensing. Our proposed project first uses ultrasonic sensors to detect obstacles ahead using ultrasonic waves. On sensing obstacles the sensor passes this data to the microcontroller. The microcontroller then processes this data and calculates if the obstacle is close enough. If the obstacle is not that close the circuit does nothing. If the obstacle is close the microcontroller sends a signal to sound a buzzer. It also detects and sounds a different buzzer if it detects water and alerts the blind. One more feature is that it allows the blind to detect if there is light or darkness in the room. The system has one more advanced feature integrated to help the blind find their stick if they forget where they kept it. A wireless rf based remote is used for this purpose. Pressing the remote button sounds a buzzer on the stick which helps the blind person to find their stick. Thus this system allows for obstacle detection as well as finding stick if misplaced by visually disabled people.

Description of Ultrasonic Blind Walking Stick

Description of Rain Sensing Automatic Car Wiper

Hardware Specifications Atmega 328 Microcontroller Servo motors Resistors Capacitors Diodes Crystal

Software Specifications Arduino Compiler MC Programming Language: Embedded C

Rain Sensing Automatic Car Wiper

Today’s car wipers are manual systems that work on the principle of manual switching. So here we propose an automatic wiper system that automatically switches ON on detecting rain and stops when rain stops. Our project brings forward this system to automate the wiper system having no need for manual intervention. For this purpose we use rain sensor along with microcontroller and driver IC to drive the wiper motor. Our system uses rain sensor to detect rain, this signal is then processed by microcontroller to take the desired action. The rain sensor works on the principle of using water for completing its circuit, so when rain falls on it it’s circuit gets completed and sends out a signal to the microcontroller. The microcontroller now processes this data and drives the motor IC to perform required action. The motor driver IC now drives a servomotor to simulate as a car wiper.

Description of Rain Sensing Automatic Car Wiper