Automated material handling org PEC UNIVERSITY TECHNOLOGY
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Transcript of Automated material handling org PEC UNIVERSITY TECHNOLOGY
AUTOMATED MATERIAL HANDLING
SUMITTTED BY
MANMEET SINGH
13209015
M.E (MECHANICAL)
FIRST YEAR
SUBMITTED TO
Dr. SANJEEV KUMAR
MATERIALHANDLING
WHAT IS MATERIAL HANDLING
Movement Storage Protection Control (Of material throughout
manufacturing) And distribution process including
consumption and disposal. Includes (raw material ,work in progress ,sub
assemblies ,finished assemblies)
MATERİAL HANDLİNG ACCOUNTS FOR:
25% of all employees, 55% of all factory space, 87% of production time 15-70% of the total cost of a manufactured product
PRINCIPLES OF MATERIAL HANDLING1) Planning Principle
(needs, desirable option ,consultation, performance)
2) Standardization Principle3) Work Principle
(minimized without sacrificing productivity)
4) Ergonomic Principle (safety, eliminate repetitive jobs )
5) Unit Load Principle6) Space Utilization Principle7) System Integration Principle8) Automation Principle9) Environment Principle (energy, impact, hazard)
10) Life Cycle Cost Principle
OBJECTIVES OF MATERIAL HANDLING
Reduce manufacturing cycle time Reduce delays, and damage Promote safety and improve working conditions Maintain or improve product quality Promote productivity Material should move as short a distance as possible Use gravity Move more material at one time Automate material handling Promote increased use of facilities Promote the use of building cube Purchase versatile equipment Develop a preventive maintenance program Maximize the equipment utilization etc.
CONSIDERATIONS IN MATERIAL HANDLING SYSTEM DESIGN
Material characteristics Flow rate Routing Scheduling Plant layout
MATERIAL CHARACTERISTICS
Category Measures
1. Physical state2. Size3. Weight4. Shape5. Condition6. Safety risk and risk
of damage
Solid, liquid, or gasVolume; length, width, heightWeight /piece, weight/unit volumeLong and flat, round, square, etc.Hot, cold, wet, etc.Explosive, flammable, toxic; fragile, etc.
FLOW RATE
Manual handlingHand trucks
Powered trucksUnit load AGV
ConveyorsAGV train
High
Low
LongShort Move Distance
Quantity of material moved
Conveyors
PLANT LAYOUT
Layout Type Characteristics Typical MH Equipment
Fixed – position
Process
Product
Large product size, low production rate
Variation in product and processing, low and medium production rates
Limited product variety, high production rate
Cranes, hoists, industrial trucks
Hand trucks, forklift trucks, AGVs
Conveyors for product flow, trucks to deliver components to stations.
ROUTING AND SCHEDULING
Routing - pick-up and drop-off locations, move distances, routing variations, conditions along the route (surface, traffic, elevation)
Scheduling - timing of each delivery Prompt delivery when required Use of buffer stocks to mitigate against late
deliveries
CATEGORIES OF MATERIAL HANDLING EQUIPMENT
1. Material transport equipment - to move materials inside a factory, warehouse, or other facility
2. Storage - to store materials and provide access to those materials when required
3. Unitizing equipment - refers to (1) containers to hold materials, and (2) equipment used to load and package the containers
4. Identification and tracking systems - to identify and keep track of the materials being moved and stored
UNIT LOAD PRINCIPLE (UNİTİZİNG)
In general, the unit load should be as large as practical for the material handling system that will move and store it A unit load is the mass that is to be moved or
otherwise handled at one time Reasons for using unit loads in material
handling: Multiple items handled simultaneously Required number of trips is reduced Loading/unloading times are reduced Product damage is decreased
UNIT LOAD CONTAINERS
(a) Wooden pallet, (b) pallet box, (c) tote box
MATERIAL TRANSPORT EQUIPMENT
Industrial trucks AGVs Robots Monorails and other rail guided vehicles Conveyors Cranes and hoists
AUTOMATION IN MATERIAL HANDLING
WHY USE AUTOMATION IN MATERIAL HANDLING
1. To increase labor productivity2. To reduce labor cost3. To mitigate the effects of labor shortages4. To reduce or remove routine manual and
clerical tasks5. To improve worker safety6. To improve product quality7. To reduce manufacturing lead time8. To accomplish what cannot be done
manually9. To avoid the high cost of not automating
AUTOMATED GUIDED VEHICLES
1. AUTOMATED GUIDED VEHICLE
What is AGV ?Material handling system that uses independently operated, Self-propelled vehicles, Guided along defined pathways. Increase efficiency and reduce costs by helping
to automate a manufacturing facility or warehouse.
Carry loads or tow objects behind them in trailers. The trailers can be used to move raw materials or finished product.
The AGV can also store objects on a bed. some AGVs use fork lifts to lift objects for storage.
AGVs are employed in nearly every industry, including, paper, metals, newspaper and general manufacturing.
HISTORY Developed by AM Barrett Jr in 1954
(overhead wire to guide a modified towing truck pulley in a grocery warehouse)
1973,Volvo developed AGV to serve assembly platforms for moving car bodies through its final assembly plants.
Today the AGV plays an important role in the design of new factories and warehouses.
COMPONENTS OF AGV Vehicle Guided path Control unit Computer interface
AGV TYPES
Driver less trains Pallet trucks Unit load carriers
DRIVER LESS TRAINS Consists of towing vehicle, which is the AGV that pulls. One or more trailers forming a train. Heavy payloads. Large distances like in a warehouse. With or without intermediate pick-up and drop-off points
along its path.
DRIVER LESS TRAIN
PALLET TRUCKS
shift palletized loads along programmed path.
the vehicle is backed into the loaded pallet by act of human operator that steers the truck and uses the forks to lift the load vaguely.
The human operator will then drive the pallet truck to its route, program its destination and the vehicle will then automatically travel to the preprogrammed destination for unloading.
Capacity -several thousand kilograms and some are capable of handling two pallets.
PALLET TRUCKS
UNIT LOAD CARRIER
These are used to move unit loads from one station to another.
Light load AGVs, up to 250 kg or less.
UNIT LOAD CARRIER
VEHICLE GUIDANCE TECHNOLOGY
Imbedded guide wires Paint strips (Optical navigation system) Magnetic tape navigation systems Self guided vehicles (Laser triangulation
navigation system)
1. IMBEDDED GUIDE WIRES
•Faster and safer•More accurate•Less costly•Simpler and less programming required
CHOOSING APPROPRIATE PATH IN WIRE GUIDED SYSTEM
Use different frequency generators for different paths.
Guide wires leading into the two separate paths at the switch have different frequency
At switch vehicle reads identification code of destination frequency and follows it.
Same frequency throughout
At switch power is turned off in all other branches except the one that the vehicle is to travel on.
Frequency select method
Path select method
Less costly More accurate and
safer Less programming
Energy consumption Embedded system Less flexible than
other types
Advantages Drawbacks
2. PAINT STRIPS (OPTICAL NAVIGATION SYSTEM)
Chemical or tape strip is fixed or painted to the floor which contain fluorescent particles that reflect UV light source from vehicle
Vehicle has an onboard sensor which allows it to detect the path.
Not typically used in plants or warehouses because floor line needs to be cleaned or reapplied as it deteriorates with time.
Useful in environment where guide wires in the floor surface is not practical.
can be easily removed and relocated if the course needs to change.
It also does not involve the expense of cutting the factory or warehouse floor for the entire travel route.
"passive" system since it does not require the guide medium to be energized as wire does.
less expensive
Repaint Cannot be used in
dirty conditions
Advantage Drawback
3. MAGNETIC TAPE/GRID NAVIGATION SYSTEMS
Magnetic tape is adhered on the surface of the floor
A sensor on underside of vehicle detects the magnetic tape
Can operate off tape path
Similar to wire guidance
4. SELF GUIDED (LASER TRIANGULATION NAVIGATION SYSTEM)
Most popular method of AGV navigation. Operate without continuously defined
pathways. Use combination of dead reckoning
(capability of a vehicle to follow a given route in the absence of a defined pathway) and beacons located throughout the plant, which can be identified by on board sensors.
Continuously verify position by comparing the calculated position with one or more known position
HOW ARE THE VEHICLES POWERED? TYPES OF BATTERIES, INDUCTIVE POWER AND FUEL CELLS
1. Most common batteries Flooded lead acid Sealed batteries NiCad Lithium ion 2. Inductive power – vehicle receives power from
plate(s) embedded in the floor. Used in some applications that require less flexibility
3. Fuel cells – performing well in limited scale use in AGVs.
The best choice of battery is based on your application. Talk to your AGV supplier to determine which battery is best for your application.
VEHICLE MANAGEMENT
Two aspects of vehicle management: Traffic control - to minimize interference
between vehicles and prevent collisions1. Forward (on-board vehicle) sensing2. Zone control
Vehicle dispatching1. On-board control panel2. Remote call stations3. Central computer control
1. ON BOARD SENSING
One or more sensors on vehicle Which detect presence of other vehicles ,
obstacle , or humans near by. More effective in straight path ,less effective
at turns, convergence points.
2. ZONE CONTROL
Zone control to implement blocking system. Zones A, B, and D are blocked. Zone C is free. Vehicle 2 is blocked from entering Zone A by vehicle 1. Vehicle 3 is free to enter Zone C.
VEHICLE DISPATCHING
1. On board control panel Manual vehicle control and programming Lowest level of sophistication Flexibility
2. Remote call station Press button at load unload stations Programmed destination with on board panel
3. Central computer control Automatic dispatching Central computer issues commands Current location information of each AGV Radio frequency commonly used for
communication
VEHICLE SAFETY FEATURES
Travelling speed(< human normal walking speed) Automatic stopping of vehicle if it strays more
than a short distance(50-150mm) –ACQUISITION DISTANCE
Obstacle detection Emergency bumper Warning lights ,bells , alarms etc
bumper
APPLICATIONS
Material transport Storage application: Integration with AS/RS Assembly line application Flexible manufacturing system Office mail delivery Hospital material transport: meal tray,
medical supplies
ROBOTS
2. INDUSTRIAL ROBOT DEFINED
A general-purpose, programmable machine possessing certain human like characteristics
Hazardous work environments Repetitive work cycle Consistency and accuracy Difficult handling task for humans Multi shift operations Reprogrammable, flexible Interfaced to other computer systems
INDUSTRIAL ROBOT APPLICATIONS
1. Material handling applications Material transfer – pick-and-place, palletizing Machine loading and/or unloading
2. Processing operations Welding Spray coating Cutting and grinding
3. Assembly and inspection
MATERIAL HANDLING APPLICATIONS This category includes the following:
Part Placement Palletizing and/or depalletizing Machine loading and/or unloading Stacking and insertion operations
The robot must have following features to facilitate material handling: The manipulator must be able to lift the parts safely. The robot must have the reach needed. The robot’s controller must have a large enough memory
to store all the programmed points so that the robot can move from one location to another.
The robot must have the speed necessary for meeting the transfer cycle of the operation.
1. PART PLACEMENT
o The basic operation in this category is the relatively simple pick-and-place operation.
o This application needs a low-technology robot of the cylindrical coordinate type.
o Only two, three, or four joints are required for most of the applications.
o Pneumatically powered robots are often utilized
2. PALLETIZING AND/OR DEPALLETIZING
o The applications require robot to stack parts one on top of the other, that is to palletize them, or to unstack parts by removing from the top one by one, that is depalletize them.
o Example: process of taking parts from the assembly line and stacking them on a pallet or vice versa.
3. MACHINE LOADING AND/OR UNLOADING:
Robot transfers parts into and/or from a production machine. There are three possible cases:1. Machine loading in which the robot loads parts into a
production machine, but the parts are unloaded by some other means.
Example: a press working operation, where the robot feeds sheet blanks into the press, but the finished parts drop out of the press by gravity.
2. Machine loading in which the raw materials are fed into the machine without robot assistance. The robot unloads the part from the machine assisted by vision or no vision.
Example: bin picking, die casting, and plastic molding 3. Machine loading and unloading that involves both loading
and unloading of the work parts by the robot. The robot loads a raw work part into the process ad unloads a finished part. Example: Machine operation
4. STACKING AND INSERTION OPERATION
In the stacking process the robot places flat parts on top of each other, where the vertical location of the drop-off position is continuously changing with cycle time.
In the insertion process robot inserts parts into the compartments of a divided carton.
RAIL GUIDED VEHICLES
3. RAIL-GUIDED VEHICLES
Self-propelled vehicles that ride on a fixed-rail system
Vehicles operate independently and are driven by electric motors that pick up power from an electrified rail
Fixed rail system Overhead monorail - suspended overhead
from the ceiling On-floor - parallel fixed rails, tracks generally
protrude up from the floor Routing variations are possible: switches,
turntables, and other special track sections
OVERHEAD MONORAIL
CONVEYORS
4. CONVEYOR SYSTEMS
Large family of material transport equipment designed to move materials over fixed paths, usually in large quantities or volumes
1. Non ‑ powered Materials moved by human workers or by
gravity
2. Powered Power mechanism for transporting materials is
contained in the fixed path, using chains, belts, rollers or other mechanical devices
CONVEYOR TYPES
1. Roller2. Skate ‑ wheel 3. Belt4. In‑ floor towline
1. ROLLER CONVEYOR
Pathway consists of a series of rollers that are perpendicular to direction of travel
Loads must possess a flat bottom to span several rollers
Powered rollers rotate to drive the loads forward
Un-powered roller conveyors also available
2. SKATE-WHEEL CONVEYOR
Similar in operation to roller conveyor but use skate wheels instead of rollers
Lighter weight and unpowered
Sometimes built as portable units that can be used for loading and unloading truck trailers in shipping and receiving
3. BELT CONVEYOR Continuous loop
with forward path to move loads
Belt is made of reinforced elastomer
Support slider or rollers used to support forward loop
Two common forms: Flat belt (shown) V-shaped for bulk
materials
4. IN-FLOOR TOW-LINE CONVEYOR
Four-wheel carts powered by moving chains or cables in trenches in the floor
Carts use steel pins (or grippers) to project below floor level and engage the chain (or pulley) for towing
This allows the carts to be disengaged from towline for loading and unloading
POWERED CONVEYOR OPERATIONS AND FEATURES
Types of motions1. Continuous - conveyor moves at constant
velocity2. Asynchronous - conveyor moves with stop-
and-go motion They stop at stations, move between stations
Another classification of conveyors:1. Single direction2. Continuous loop3. Recirculating
(a) Single direction conveyor
(b) Continuous loop conveyor
CRANES AND HOISTS
5. CRANES AND HOISTS
Handling devices for lifting, lowering and transporting materials, often as heavy loads
Cranes Used for horizontal movement of materials
Hoists Used for vertical lifting of materials
Cranes usually include hoists so that the crane-and-hoist combination provides Horizontal transport Vertical lifting and lowering
BRIDGE CRANE
GANTRY CRANE------TYPES---- Double gantry Half gantry Cantilever
gantry
Half gantry
JIB CRANE
ANALYSIS OF MATERIAL TRANSPORT SYSTEMS
1. Charting techniques in material handling2. Vehicle based system3. Conveyor analysis
ANALYSIS OF MATERIAL TRANSPORT SYSTEMS
Analysis of vehicle-based systems From-to charts and network diagrams Types of systems: industrial trucks, AGVS, rail-
guided vehicles, and asynchronous conveyor operations
CHARTING TECHNIQUES IN MATERIAL HANDLING (FROM –TO CHART)
FROM
TO 1 2 3 4 5
1 0 9/50 5/120 6/205 0
2 0 0 0 0 9/80
3 0 0 0 2/85 3/170
4 0 0 0 0 8/85
5 0 0 0 0 0
FROM –TO CHART showing flow rates, (loads per hr/travel distance)
Flow diagram showing material deliveries between load/unload stations
ANALYSIS VEHICLE BASED SYSTEM
Tc = delivery cycle time (min/del) TL = time to load (min)—0.75 min Tu = time to unload (min)---0,5 min Ld = distance b/w load to unload
(110m) Le = distance b/w unload to load
(80 m) v = vehicle velocity (50 m/min)
Tc ideal value because it ignores Traffic congestion Reliability problems etc
LOAD
UNLOAD
5540
20
20
Direction of AGV
Guide path
AGV
Tc = TL +[Ld/v ]+ [Le/v] + Tu
Tc= 0.75 + [110/50]+[80/50]+ 0.5Tc= 5.05 min
1. RATE OF DELIVERIES PER VEHICLE Possible time loss include1) Availability ( A) -proportion of total shift time that te
vehicle is operational and not broken down or being repaired)
2) Traffic congestion ( Tf)- blocking, waiting in queue etc
Many vehicles Tf decreases ,value ranges from 0.85 to 1
3) Efficiency (E)-of manual drivers if any(worker efficiency)
if not apply is taken as unity (1) AT = available time (min/hr per vehicle)
Rdv = rate of deliveries per vehicle (del/hr per
vehicle)
AT = 60× A × Tf × E
Rdv = AT Tc 1
2. NUMBER OF VEHICLES REQUIRED
Rf = specified delivery schedule or total delivery requirements (del/ hr per vehicle)
WL = Work load(min/hr) n = number of vehicle required
n = WL AT
n = Rf Rdv
2
From 1 and 2
LIMITATIONS OF AUTOMATED MATERIAL HANDLING SYSTEMS
Additional investment Lack of flexibility Vulnerability to downtime whenever there is
breakdown Additional maintenance staff and cost Cost of auxiliary equipment. Space and other requirements
ENDTHANK YOU