Define and describe the attributes of Fixed Automation.
Fixed automation is used where the sequence of processing is fixed by the equipment configuration si fixed by the process.
Initial equipment cost is high but the cost is justified as they production rate is high and so the cost will be spread over many units.
Example: Printing press, tin foil manufacture
Define and describe the attributes of Programmable Automation.
•The configuration of the equipment must accommodate changes in the operation sequence. The operation sequence is controlled by a programme allowing new programs to be prepared and hence new sequences operated to produce new products.
•There is considerable investment in more general purpose equipment, such as industrial robots and there is a lower production rate in comparison to fixed automation ease of re-configurability suits batch production.
•Each time a system is reconfigures there is a corresponding cost and down-time with regards to re-programming, resetting tools and fixtures.
Define and describe the attributes of flexible automation.
•Flexible automation is an extension of programmable automation.
•It is capable of producing a variety of parts with no time lost for changeover.
•This can be done by using all manner of general purpose equipment.
•The system can produce various combinations of products at once.
Example: CNC lathe or CNC mill
Reasons for automation
•To increase labour productivity
•To reduce labour cost
•To mitigate the effects of labour shortage (the case in developed countries)
•To reduce or eliminate the manual or clerical tasks
•To improve worker safety
•To improve product quality
•To reduce the time elapsed between the customer order and product delivery
•To accomplish processes that can not be done manually
•To avoid the high cost of not automating
Reasons to use humans.
1.The task is technologically too difficult to automate
2.The product life cycle is short
3.The product is customized
4.To cope with variation in demand
5.To reduce risk of product failure
Humans are more flexible than any automated machines and can sometimes be much less expensive.
Manual labour is still very much required in...
2.Programming and computer operations
3.Engineering project work
Human advantage vs machine advantage
- Sense unexpected stimuli
- Adapt to change
- Develop new solutions
- Cope with abstract problems
- Generalise from observations
- Make difficult decisions based on incomplete data
- Perform repetative tasks consistently
- Store large amounts of data
- Retrieve data from memory reliably
- Apply high forces and power
- Make routine descisions quickly
- Perform simple decisions quickly
What does USA stand for?
Understand- the existing process
Comprehend the process in all details
Set the relationship between the input and the output
Simplify- the process
Check the purpose of each step
Check if the step is necessary
Check if the technology for each step is suitable
Can steps be combined or done simultaneously?
Automate- the process
Only after the processes are simplified, automation can be considered.
The 10 strategies for automation.
1.Specialisation of operations
4.Integration of operations
6.Improved material handling and storage
8.Process control and optimization
9.Plant operations control
10.Computer integrated manufacturing
Automation Migration Strategy
Phase 1: Manual production (quick and low cost tooling to get started)
Phase 2: Automated production (use of single station automated cells operating independently)
Phase 3: Automated integrated production (using multi-station automated cells operating independently)