RE:agricultural Robotics (Download Full Seminar Report)
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As farms grow in size, together with the size of the equipment used on them, there is a need for ways to automate processes, previously performed by the farmer himself, such as controlling the fields for pests. These tasks are perfectly suited for autonomous robots, as they often require numerous repetitions over a long period of time and over a large area. The use of robots is a rather new development as most of the existing solutions for automatic supervision, is designed for standard farm equipment, such as tractors, combines and pesticide sprayers. One such solution is agricultural robot.
In most cases a small agricultural robot would be ineffective in performing farming jobs, as these often require a large quantity of materials, either to put into the ground, such as seeds or fertilisers, or to take from the ﬁeld during harvest. But when dealing with monitoring and mapping of ﬁelds or precision spraying of pesticides, a smaller robot is ideal, as it is more gentle on the crops but also to the ground. This is due to the lower weight compared to a tractor, causing much lesser soil compaction. The degree of soil compaction is important to consider, especially when dealing with monitoring and mapping as this is often performed multiple times throughout the year, as soil compaction can cause a number of problems, such as reduced crop growth and denitriﬁcation.
Agriculture involves the systematic production of food, feed, fibre, and other goods. In addition to producing food for humans and animals, agriculture also produces cut flowers, timber, fertilizers, animal hides, leather, and industrial chemicals. Food is anything made up of carbohydrates, fats, water or a protein that’s eaten by animals or people for nutrition or pleasure. Fodder is food made from vegetable or animal bi-products that is for animals including livestock, pigs, sheep, and chicken. Fibre is a class of material including cloth, cotton, linen, jute, flax, ramie, and sisal. Agriculture comes from two Latin words: ager which means a field culture which means cultivation, the tillage of the soil. A lot of the world’s workers (42%) are involved in agriculture in some way.
A robot is a machine that can be programmed and reprogrammed to do certain tasks and usually consists of a manipulator such as a claw, hand, or tool attached to a mobile body or a stationary platform. Autonomous robots work completely under the control of a computer program. They often use sensors to gather data about their surroundings in order to navigate. Tele-controlled robots work under the control of humans and/or computer programs. Remote-controlled robots are controlled by humans with a controller such as a joystick or other hand-held device. The word ‘robot’ came from the Czech word ‘robota’, which means forced labor, or work. It was first used in the play R.U.R., Rossum’s Universal Robots, written in 1921 by a Czech playwright named Karel Capeck. Isaac Asimov was the first person to use the term ‘robotics in “Runaround,” a short storypublished in 1942.
An Agricultural Robot is a robot deployed for agricultural purposes. The main area of application of robots in agriculture is at the harvesting stage. Fruit picking robots and sheep shearing robots are designed to replace human labour. The agricultural industry is behind other complementary industries in using robots because the sort of jobs involved in agriculture are not straightforward, and many repetitive tasks are not exactly the same every time.
2.1 BLOCK DIAGRAM:
Agricultural Robot tracks the migration of agriculture to incorporate intelligent machines used in farming, with agricultural robot articles, agricultural robot videos, and conversation you may wish to join in about emerging farming automation.
Figure 2.1: Block Diagram of Agricultural Robot
The functional block diagram of Agricultural Robot is as shown in Figure 2.1and the list of components can be discussed below
2.2 LIST OF COMPONENTS
1. AT89C52 micro controller
2. IC ULN 2003
3. 16*2 dot matrix display
4. 7805 voltage regulator
5. IN 4007 diodes - 2 no’s
6. 100 uf capacitors - 2 no’s
7. 10 uf / 16 V capacitor - 1 no
8. 33 pf capacitors - 2 no’s
9. 1.1 kΩ resistors - 2 no’s
10. 8.2 k Ω resistor - 1 no
11. BC 557 pnp transistors - 4 no’s
12. Water sprinkler motor
13. Seed sowing motor
14. Robot driving motors - 2 no’s
16. DIP switch - 1 no’s
18. 230V Transformer
2.3 POWER SUPPLY SECTION:
The Power Supply is a Primary requirement for any system to start. The required DC power supply for the base unit as well as for the recharging unit is derived from the mains line. For this purpose centre tapped secondary of 12V-012V transformer is used. From this transformer we getting 5V power supply. The +5V output is a regulated output and it is designed using 7805 positive voltage regulator. This is a 3 Pin voltage regulator, can deliver current up to 800 milliamps.
Rectification is a process of rendering an alternating current or voltage into a unidirectional one. The component used for rectification is called ‘Rectifier’. A rectifier permits current to flow only during positive half cycles of the applied AC voltage. Thus, pulsating DC is obtained .To obtain smooth DC power additional filter circuits required. The circuit diagram for power supply is as shown in Figure 2.3.
Figure 2.2: circuit diagram of power supply
A diode can be used as rectifier. There are various types of diodes. However, semiconductor diodes are very popularly used as rectifiers. A semiconductor diode is a solid-state device consisting of two elements is being an electron emitter or cathode, the other an electron collector or anode. Since electrons in a semiconductor diode can flow in one direction only-from emitter to collector-the diode provides the unilateral conduction necessary for rectification.
The rectified Output is filtered for smoothening the DC, for this purpose capacitor is used in the filter circuit. The filter capacitors are usually connected in parallel with the rectifier output and the load. The AC can pass through a capacitor but DC cannot, the ripples are thus limited and the output becomes smoothened. When the voltage across the capacitor plates tends to rise, it stores up energy back into voltage and current. Thus, the fluctuation in the output voltage is reduced considerable.
The transformer is a device that transfers electrical energy from one electrical circuit to another electrical circuit through the medium of magnetic field and without a change in the frequency. The electric circuit which receives energy from the supply mains is called primary winding and the other circuit which delivers electric energy to the load is called the secondary winding.
Figure 2.3: 230V Transformer
This is a very useful device, indeed. With it, we can easily multiply or divide voltage and current in AC circuits. Indeed, the transformer has made long-distance transmission of electric power a practical reality, as AC voltage can be "stepped up" and current "stepped down" for reduced wire resistance power losses along power lines connecting generating stations with loads. At either end (both the generator and at the loads), voltage levels are reduced by transformers for safer operation and less expensive equipment. A transformer that increases voltage from primary to secondary (more secondary winding turns than primary winding turns) is called a step-up transformer. Conversely, a transformer designed to do just the opposite is called a step-down transformer. The transformer is as shown in figure 2.4.
This is a step-down transformer, as evidenced by the low turn count of the primary winding and the high turn count of the secondary. As a step-down unit, this transformer converts high-voltage, low-current power into low-voltage, high-current power. The larger-gauge wire used in the secondary winding is necessary due to the increase in current. The primary winding, which doesn't have to conduct as much current, may be made of smaller-gauge wire.
2.4 AT89C52 MICRO CONTROLLER:
Compatible with MCS-51 Products.
8K Bytes of In-System Reprogrammable Flash Memory.
Endurance: 1,000 Write/Erase Cycles.
Fully Static Operation: 0 Hz to 24 MHz.
Three-level Program Memory Lock.
256 x 8-Bit Internal RAM.
32 Programmable I/O Lines.
Three 16-bit Timer/Counters.
Eight Interrupt Sources.
Programmable Serial Channel.
Low Power Idle and Power Down Modes
2.4.2 PIN DIAGRAM AND ITS DESCRIPTION:
The microcontroller generic part number actually includes a whole family of microcontrollers that have numbers ranging from 8031to 8751 and are available in N-Channel Metal Oxide Silicon (NMOS) and Complementary Metal Oxide Silicon (CMOS) construction in a variety of package types.
AT89C52 microcontroller is a 4Kbytes of Flash Programmable and Erasable Read Only Memory (PEROM). The device is manufactured using Atmel’s high density non-volatile memory technology and is compatible with the industry standard MCS-51 instruction set and pin out. The on-chip Flash allows the program memory to be reprogrammed in-system or by a conventional non-volatile memory programmer. By combining a versatile 8-bit CPU with Flash on a monolithic chip, the Atmel AT89C52 is a powerful microcomputer which provides a highly flexible and cost effective solution to many embedded control applications