The objective of this project is to develop a robot that autonomously moves pallets around a Model warehouse floor. The Automated Guided Vehicle, AGV
uses several sensor suites to characterize its behaviors. An infrared remote control allows the robot to dynamically receive part orders. Its capabilities are enhanced by the ability to send and receive tasks to an Automated Storage and Retrieval System through RF data communication. While operating, infrared and Proximity sensors allow the vehicle to avoid collisions.
AGV control is usually done locally. An alternate implementation involves a remote control. This schema opens up a full set of new applications
such as coordination of tasks in multi-AGV systems, providing at the end more flexible manufacturing systems. Based on the benefits provided by the remote
control, an adequate architecture for AGV systems may consist in an external controller sending and receiving, through a wireless network, the control
commands to the vehicle. Automated guided vehicles (AGVs) increase efficiency and reduce costs by helping to automate a manufacturing facility or warehouse.
The first AGV was invented by Berrett Electronics in 1953. The AGV can tow objects behind them in trailers to which they can autonomously attach. The trailerscan
be used to move raw materials or finished product. The AGV can also store objects on a bed. The objects can be placed on a set of motorized rollers (conveyor) and then pushed off by reversing them. AGVs are employed in nearly every industry, including, pulp, paper, metals, newspaper, and general manufacturing. Transporting materials such as food, linen or medicine in hospitals is also done.
An AGV can also be called a laser guided vehicle (LGV). In Germany the technology is also called Fahrerlose Transport system (FTS) and in Sweden förarlösa truckar.
Lower cost versions of AGVs are often called Automated Guided Carts (AGCs) and are usually guided by magnetic tape. AGCs are available in a variety of models and can be used to move products on an assembly line, transport goods throughout a plant or warehouse, and deliver loads. The first AGV was brought to market in the 1950s, by Barrett Electronics of Northbrook, Illinois, and at the time it was simply a tow truck that followed a wire in the floor instead of a rail. Over the years the technology has become more sophisticated and today automated vehicles are mainly Laser navigated e.g. LGV (Laser Guided Vehicle). In an automated process, LGVs are programmed to communicate with other robots to ensure product is moved smoothly through the warehouse, whether it is being stored for future use or sent directly to shipping areas. Today, the AGV plays an important role in the design of new factories and warehouses, safely moving
goods to their rightful destination.
Limitation of Existing System:
·Supports only Manual operations.
· It can’t control from remote area.
· Doesn’t provide status report of the appliances.
· Can’t control from Mobile phone and Tablets.
An Automated Guided Vehicle(AGV) is a robot that follows markers or wires in the floor, or uses vision or lasers. They are most often used in industrial applications to move materials around a manufacturing facility or a warehouse. Application of the automatic guided vehicle has broadened during the late 20th century. To overcome the drawbacks of the existing system that is mentioned above we have introduced new concept which is Automated Guided Vehicle using PLC Application. In this proposed
system we are able to control the Guided Vehicle from anywhere. We provide the connectivity so that it can be control from anywhere. It breaks the limitation of the existing system of access to the limited area.
It supports following extra features which are not supported by the existing system:
i. Can control appliances from Wireless Remote
ii. It provides us the status report of each appliance.
iii. It also provides scheduler for controlling appliances.
Block Diagram :
Block Diagram of Project
As we see in the above figure, the remote control, proximity sensor, infrared sensor are connected at input & power supply connected to programmable logic control. At output we connected three motors with encoder also the indicator. The remote control having three buttons one for call the AGV & other two buttons provided to give command of destination. proximity sensor used to detect the obstacle in front of AGV. Then the infrared sensor used to sense the path (for line follower).We are using D.C. with break instead of stepper or servo motor because we are using the encoder which gives us feedback, but in stepper motor we does not get the feedback also the price of stepper & servo motor is more than the D.C. motor. Two motors out of three are used as left & right & third one used for tray. To control the AGV we are using PLC. The paths are programmed in the plc & according to requirement one of them is selected. We are providing three indicators If any person come in path of AGV then 1st indicator will indicate that person to move away from the path. Then 2nd indicator will indicate low battery signal. Third indicator will indicate the AGV is reached at destination point, and alarm will be beeped to indicate that person. The power supply required to run the is AGV 24V DC.
Definition of PLC:- A digitally operating electronic apparatus which uses a programming memory for the internal storage of instructions for implementing specific functions such as logic, sequencing, timing, counting and arithmetic to control through digital or analog modules, various types of machines or process.
The operation of a programmable controller is relatively simple. The input/output (I/O) system is physically connected to the field devices that are encountered
in the machine or that are used in the control of a process. These field devices may be discrete or analog input/output devices, such as limit switches, pressure transducers, push buttons, motor starters, solenoids, etc. The I/O interfaces provide the connection between the CPU and the information providers (inputs) and controllable devices (outputs). During its operation, the CPU completes three processes:
1. It reads, or accepts, the input data from the field devices via the input interfaces,
2. It executes, or performs, the control program stored in the memory system, and
3. It writes, or updates, the output devices via the output interfaces.
This process of sequentially reading the inputs, executing the program in memory, and updating the outputs is known as scanning. Figure 4.3 illustrates a graphic
representation of a scan.
PLC Ladder Logic for line follower Robot:
RF Based Wireless Remote using RX-TX MODULES
This circuit utilizes the RF module (Tx/Rx) for making a wireless remote, which could be used to drive an output from a distant place. RF module, as the name suggests, uses radio frequency to send signals. These signals are transmitted at a particular frequency and a baud rate. A receiver can receive these signals only if it is configured for that frequency.
A four channel encoder/decoder pair has also been used in this system. The input signals, at the transmitter side, are taken through four switches while the outputs are monitored on a set of four LEDs corresponding to each input switch. The circuit can be used for designing Remote Appliance Control system. The outputs from the receiver can drive corresponding relays connected to any household appliance.
This circuit utilizes the RF module (Tx/Rx) for making a wireless remote, which could be used to drive an output from a distant place. RF module, as the name suggests, uses radio frequency to send signals. These signals are transmitted at a particular frequency and a baud rate. A receiver can receive these signals only if it is
configured for that frequency.
Motor Driver for AGV:In our project we are using relays to build motor driver kit. In this driver circuit we use four relays to drive a single motor i.e. we are using eight relays to drive two motors.
The circuit diagram motor driver is as shown below.
Motor Driver Circuit
As we see in fig. we get output at port y0, y1, y2 & y3 from PLC. This output of PLC gives -24V output. Which is connected to one terminal of relay coil. At other terminal we provide +24V supply. We give +24V to all positive terminal of relay coil. We use two relays to each output port of PLC. Out of them y0 & y2 are used to forward
motor and other are y1 & y3 are used to reverse motor. To forward left motor we use relay1 & relay2. We connect the NO terminal of relay1 to positive terminal of motor. Also NO terminal of relay2 to negative terminal of motor.
The common terminal of relay1 is connected to +12V supply and common terminal of relay2 is connected to -12V supply.
To reverse left motor we use relay3 & relay4. The NO terminal of relay3 is connected to positive terminal of motor and NO terminal of relay4 is connected to negative terminal of motor. The common terminal of relay3 is connected to -12V supply and common terminal of relay4 is connected to +12V supply.
Similarly we made connection for right motor.
APPLICATIONS of AGV :
Raw Material Handling:
AGVs are commonly used to transport raw materials such as paper, steel, rubber, metal, and plastic. This includes transporting materials from receiving to the
warehouse, and delivering materials directly to production lines.
Work-in-Process movement is one of the first applications where automated guided vehicles were used, and includes the repetitive movement of materials throughout the manufacturing process. AGVs can be used to move material from the warehouse to production/processing lines or from one process to another.
Pallet handling is an extremely popular application for AGVs as repetitive movement of pallets is very common in manufacturing and distribution facilities. AGVs can
move pallets from the palletizer to stretch wrapping to the warehouse/storage and/or to the outbound shipping docks.
Finished Product Handling:
Moving finished goods from manufacturing to storage or shipping is the final movement of materials before they are delivered to customers. These movements often
require the gentlest material handling because the products are complete and subject to damage from rough handling. Because AGVs operate with precisely controlled navigation and acceleration and deceleration this minimizes the potential for damage making them an excellent choice for this type of application.
Automatic loading of trailers is a relatively new application for automated guided vehicles and becoming increasingly popular. AGVs are used to transport and load
pallets of finished goods directly into standard, over-the-road trailers without any special dock equipment. AGVs can pick up pallets from conveyors, racking, or staging lanes and deliver them into the trailer in the specified loading pattern.
AGVs are used to transport rolls in many types of plants including paper mills, converters, printers, newspapers, steel producers, and plastics manufacturers.
AGVs can store and stack rolls on the floor, in racking, and can even automatically load printing presses with rolls of paper.
Paper and Print:
AGVs can move paper rolls, pallets, and waste bins to provide all routine material movement in the production and warehousing (storage/retrieval) of paper,
newspaper, printing, corrugating, converting, and plastic film.
Food and Beverage:
AGVs can be applied to move materials in food processing (such as the loading of food and/or trays into sterilizers) and at the “end of line,” linking the
palletizer, stretch wrapper, and the warehouse. AGVs can load standard, over-the-road trailers with finished goods, and unload trailers to supply raw materials or packaging materials to the plant. AGVs can also store and retrieve pallets in the warehouse.