Difference between revisions of "System Architecture Design"
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'''Process''' | '''Process''' | ||
| − | + | Prepare the Design Constraints. Consider these topics: | |
| + | '''The price of the product.''' | ||
| + | Consider how much the product must cost. This includes sales price, development cost, HW cost, etc. | ||
| + | |||
| + | '''Development time.''' | ||
| + | |||
| + | Consider the time it must take to develop the system-to-be. | ||
| + | |||
| + | When can the production start? When can the sale start? | ||
| + | |||
| + | '''Performance.''' | ||
| + | |||
| + | Consider the performance of the product when it is to be used. Is it an expensive high quality product or is it a low price product which is to be sold in large quantities?. If it is a product for which a customer has paid a large amount of money, then no defects are accepted. Is the system-to-be a product which must be safe in use, optimal performance is necessary and malfunctions are not accepted. Examples could be: Electronically controlled wheelchairs, systems for use in hospitals, etc. | ||
| + | |||
| + | Another important aspect is which part of the world it is planned to sell the product-to-be. Different countries have different legislations. If you are planning to sell the system-to-be in European countries you must test your product in compliance with EU regulation and consequently mark your product with the CE certification. | ||
| + | |||
| + | '''Reliability and lifetime.''' | ||
| + | |||
| + | The reliability and lifetime must be considered. Is the system-to-be a product which must be safe to use, then it is necessary that the reliability and lifetime are high and no failures are accepted. Examples could be: Electronically controlled wheelchairs, systems for use in hospitals, etc. | ||
| + | |||
| + | '''Already developed parts.''' | ||
| + | |||
| + | If it is important to use already developed parts, these must be considered early in the project phase, because it will have an effect on the selection of the technical platform. It is not certain that these parts fit completely into the system-to-be. You have to consider how they worked in previous projects. Do they fit into the new project? Was the design as wished or did some parts have defects? Are they good enough or do you have to design new parts? | ||
| + | |||
| + | '''Service and maintenance''' | ||
| + | |||
| + | Consider service and maintenance. No matter how well- developed the system-to-be is, it will sometimes fail or must be maintained. Maintenance can be different sorts of adjustments of the system-to-be. Sometimes replacing old HW or changing SW. | ||
| + | |||
| + | '''Type of System.''' | ||
| + | |||
| + | Consider which type of system is wanted. | ||
| + | |||
| + | It is possible to design systems containing much or little electronics. The more electronics the more features are normally possible. The choice could be a system that contains no electronics at all. It is, for instance, possible to construct a heating installation with no electronics and where the parts used are purely mechanical featuring only a few adjustment possibilities. It is also possible to construct a heating installation containing much electronics. In this case there are many adjustment possibilities, and it will be easy to guide the user. | ||
| + | |||
| + | ===Partitioning=== | ||
| + | |||
| + | There is several ways to partition the general blocks from the architectural block diagram into software and hardware parts. In EUDP we recommend to follow the instructions given at [[Design Partitioning]]. | ||
| + | |||
| + | Having defined the most effective partitioning prepare the necessary class diagrams to describe the software partition and corresponding diagrams for the hardware. | ||
== Why == | == Why == | ||
| + | |||
| + | In order to find the most effective partitioning that at the same time respects the constraints and gives the best value for the customer it is essential to define the constraints for the project. Without proper definition of the constraints the design space is wide, but may not give the customer the best value. | ||
| + | |||
| + | ==Example== | ||
Revision as of 08:29, 3 September 2012
Contents
What
An overall system architecture divided into hardware and software specifications
How
The dish
An overall system architecture divided into hardware and software specifications
Ingredients
- General Architecture Analyse artefacts
Process
Prepare the Design Constraints. Consider these topics:
The price of the product.
Consider how much the product must cost. This includes sales price, development cost, HW cost, etc.
Development time.
Consider the time it must take to develop the system-to-be.
When can the production start? When can the sale start?
Performance.
Consider the performance of the product when it is to be used. Is it an expensive high quality product or is it a low price product which is to be sold in large quantities?. If it is a product for which a customer has paid a large amount of money, then no defects are accepted. Is the system-to-be a product which must be safe in use, optimal performance is necessary and malfunctions are not accepted. Examples could be: Electronically controlled wheelchairs, systems for use in hospitals, etc.
Another important aspect is which part of the world it is planned to sell the product-to-be. Different countries have different legislations. If you are planning to sell the system-to-be in European countries you must test your product in compliance with EU regulation and consequently mark your product with the CE certification.
Reliability and lifetime.
The reliability and lifetime must be considered. Is the system-to-be a product which must be safe to use, then it is necessary that the reliability and lifetime are high and no failures are accepted. Examples could be: Electronically controlled wheelchairs, systems for use in hospitals, etc.
Already developed parts.
If it is important to use already developed parts, these must be considered early in the project phase, because it will have an effect on the selection of the technical platform. It is not certain that these parts fit completely into the system-to-be. You have to consider how they worked in previous projects. Do they fit into the new project? Was the design as wished or did some parts have defects? Are they good enough or do you have to design new parts?
Service and maintenance
Consider service and maintenance. No matter how well- developed the system-to-be is, it will sometimes fail or must be maintained. Maintenance can be different sorts of adjustments of the system-to-be. Sometimes replacing old HW or changing SW.
Type of System.
Consider which type of system is wanted.
It is possible to design systems containing much or little electronics. The more electronics the more features are normally possible. The choice could be a system that contains no electronics at all. It is, for instance, possible to construct a heating installation with no electronics and where the parts used are purely mechanical featuring only a few adjustment possibilities. It is also possible to construct a heating installation containing much electronics. In this case there are many adjustment possibilities, and it will be easy to guide the user.
Partitioning
There is several ways to partition the general blocks from the architectural block diagram into software and hardware parts. In EUDP we recommend to follow the instructions given at Design Partitioning.
Having defined the most effective partitioning prepare the necessary class diagrams to describe the software partition and corresponding diagrams for the hardware.
Why
In order to find the most effective partitioning that at the same time respects the constraints and gives the best value for the customer it is essential to define the constraints for the project. Without proper definition of the constraints the design space is wide, but may not give the customer the best value.
