Systems and Control Flashcards
QRM?
Quick response manufacturing
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AMT?
Advanced manufacturing technology
Quick response manufacturing - ADVANTAGES?
Lower working capital needed (stock minimised)
Quicker response attractive to potential clients - gain larger market share
Reduces cost of quality - minimises waste
Quick response manufacturing - DISADVANTAGES?
More reliance on suppliers to react to demand - poor supply could result in inability to meet demand
Large demand changes can cause problems - may be unable to high production volume efficiently
Requires role changes - may cause friction
Concurrent manufacturing?
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House of quality?
Customer requirements - list of requirements (surveys etc)
Technical requirements - measurable product characteristics
Planning matrix - importance of requirements and competitor performance
Interrelationship matrix - relationship between customer and technical requirements
Technical correlation - if technical requirements compromise design
Technical priorities / benchmarks / targets - quality targets against specification measured
FMS?
Flexible manufacturing systems
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Flexible manufacturing systems - ADVANTAGES?
Increased productivity (automation)
Shorter lead time
Lower labour costs
Improved quality (automated)
Flexible manufacturing systems - DISADVANTAGES?
High set up costs
Require lots of planning
CIM?
Computer integrated manufacture
Systems that combines separate technologies - all teams can share information and communicate
Includes designing in CAD, planning most efficient workflow, controlling operations of machines, ordering stock and invoicing customers
Computer integrated manufacture - DISADVANTAGES?
Dependence on computer data to integrate in operations - compatibility problems with different CIM brands
Data may become corrupt - cause machinery to malfunction (product data management system used)
PDM?
Product data management systems
Manages product data passing from design to manufacture
Includes 3D models, CAD drawings, CNC programs etc
When change made to 1 database - changes everything (tracks changes)
Product data management - ADVANTAGES?
Reduced time to market (data instantly available)
Improved productivity
Improved control - assures everyone working on latest version
ERP?
Enterprise resource planning systems
Integrates all departments and data onto 1 computer
Links data from different departments together - all information needed instantly available (customer credit rating, product stock level, delivery schedule)
Enterprise resource planning management systems - ADVANTAGES?
More information kept up to data without errors
Enterprise resource planning management systems - DISADVANTAGES?
Expensive set up
Lots of training required
Dependent on all departments working together
Lean manufacturing and JIT
No warehouses full of materials waiting to be used (arrive when needed)
Product produced when needed
JIT: right materials/components arrive at right time in the right amount
Reduces waste and overstocking = efficient
Relies on accurate data/forecasts - error could stop production
5 stages of lean manufacturing?
Value - focus on what customer is prepared to pay for Value system - Flow Pull Perfection
Pull tools - Kanban?
Cards indicate when to ‘pull’ materials through production
‘Pull’: producing in response to demand
‘Push’: producing whether or not they’re needed
Production Kanban: operations to be carried out
Transportation Kanban: location it needs to go
Kanban - ADVANTAGES?
Reduces number of work in progress products
Restricts supply until it’s needed
Perfection tools - Kaizen?
Small changes made to production process to give improvements
Carried out on regular basis - continuous improvement
Flexible manufacturing cells?
Grouping similar products into families - processed on the same equipment = manufacture sped up
Product progressively processed from 1 workstation to another
Modular - cell can be closed to be upgraded (another can take its place)
Types of manufacturing cells?
Functional: perform specific function - cutting holes, milling Group technology (mixed model): operations for different product lines Product focused: focus on 1 product - manufactured through series of operations
CAQ?
Computer aided quality control systems
Coordinate measuring machine (CMM) - accurate measurements:
-probe: touches surface to determine size
-optical/laser: checks size and creates 3D image
Optical character recognition: recognises writing
Barcode readers: ensure correct components go together
Computer aided manufacture - ADVANTAGES?
Greater control over production - allows fully automated production
No humans = safer working environment - less risk, lower costs, improved productivity, accuracy, fewer errors
Flexible production - CNC machinery can be reprogrammed quickly (reduced set up)
Production can be determined by demand - can react quickly
Improved productivity and reliability - machines more consistent in maintaining high quality
Reduced manufacturing time - most efficient production determined by software
Computer aided manufacture - DISADVANTAGES?
Expensive start up cost
Causes unemployment (less human involvement)
Lower worker morale - machine babysitting jobs
Automated material handling systems?
Transportation of materials and components
Stages: unloading from truck, move to assembly line, testing etc
Need specialist equipment for each stage (unloading requires fork-lift truck)
Automated systems use robots and replace humans - work automatically (without significant intervention)
Downsizes workforce
ASRS?
Automated storage and retrieval systems
Robotic system - sorts, stores and retrieves items in warehouse
Computer controls transportation
Stock stored in racking systems
Selects correct component from rack, retrieve it by crane and place in conveyor/automated guided vehicle
Lowers labour costs and gives employees skills to control system
AGV?
Automated guided vehicle
Moves parts between machines
Independently powered vehicles guided by frequency wires buried in floor or laser guided navigation
Automated guided vehicle - TYPES?
Towing - pull trailers
Unit load - decks …?
Pallet - transport palletised loads (wood grid floor)
Fork lift - lift loads at different heights
Light load - transport light loads through light manufacturing environment (work in areas of little space)
Assembly line - adaption of light load …
Impact of manufacturing technologies on employment?
Reduction of workforce - machines increasingly efficient
Doesn’t eliminate skilled professionals (product designers)
Computers increase skill required - CAD etc
Production lines have become more automated - staff need more skill flexibility (multi-skilled)
Manufacturing is creative - everything needs to be designed (more efficient = save money or helping it sell more)
Robots in automated manufacturing systems?
Computer systems control industrial machinery - replacing human operators
Manipulates and transports parts/tools to manufacture
More flexible than CNC machines
Can assemble work and complete processes such as welding
Equipped with sensory feedback (vision)
Will intelligently work with humans to judge when it’s safe to operate - to need for guards
Levels of complexity of manufacturing robot tasks?
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Robots for manufacturing - ADVANTAGES?
Ideal for repetitive tasks requiring precision
Used in hazardous environments not suitable for humans
Can carry heavy loads
Reprogrammable - flexible in responding to change
Programmed once - used forever
No human error (losing concentration)
Work continually - cost effective
Robots for manufacturing - DISADVANTAGES?
Can’t learn or make decisions when the required data doesn’t exist
Not as flexible as humans - harder to program
Very expensive
Humans can’t enter robot working areas (safety)
High cost making robot cells safe
Different robot brands work differently - maintenance crew need different specialist training for each
No standard robot programming language - problems working between different brands
Industrial applications of artificial intelligence?
Exhibit human intelligence
Learn and adapt through experience
Expert systems?
Apply reasoning skills to reach a conclusion (process large amounts of data)
Simulations generate realistic simulated worlds where design testing can be done (no physical prototyping)
Combined with voice recognition - designers could talk to computer to solve problem (act as coworker)
Autonomous robots?
Robots could learn the skills needed for any particular environment - rather than programming for each specific repetitive task
Must manipulate and ‘feel’ objects like humans - typical robots have 6 degrees of freedom - perform small range of tasks
Human type hands have 20 degrees and touch sensors with AI systems - decide best way to manipulate object
Flow chart?
Schematic representation of a process
Indicates what should happen at each stage
Open loop control system?
No feedback information on quality at each stage
Process continues without interference from control system - even when output changes
Can’t detect / correct errors in the process
Used in basic processes - low cost
Closed loop control system?
Feedback makes decisions about changes to process
Improved tracking of performance
Early detection of faults
Require no human intervention - automatic
