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4.11.1 Example Project 1 – Adding Field Elements to an Existing System

[Please note that the solution given here is for this example only. Other viable solutions may be possible and each must be evaluated for a given project.]

A $10 million project to add 30 full matrix changeable message signs [assuming $330,000 per sign] to an existing system that had five identical signs already deployed. No changes are needed to the existing central or field equipment. The system was initially designed to accommodate these additional signs so no additional software is needed. Assumptions are: 1] the communications and power for the signs have already been deployed under a previous construction project, 2] the initial system has been completed and the system is working, 3] the contractor will deploy the signs, poles and foundations, controllers, and wire the controllers into the signs, 4] the agency will add configuration information about the signs at the central computer, and 5] the construction costs have been included in the cost of the signs.

In this example, even though this is a high dollar amount, little systems engineering is needed because the risks are low and no decisions or trade studies are required. This same example can be applied to many current ITS projects such as adding: field masters and traffic signals to a traffic signal control system, cameras to an existing surveillance system, or detectors to an existing detection system. Adding elements to existing systems which do not require additional design, coding, or development [other than the construction design needed for the signs and controllers at each location] would require the minimum amount of formal systems engineering. However, it is recommended that updates to existing plans and reviews be performed to ensure that the original design and implementation is not adversely affected as a result of adding the elements.

Process Step Estimated Level of Effort Check list of supporting activities Check list of issues Check list of risks Examples

Feasibility Study

None

     

Completed and approved as part of the original project.

  • Planning

Low

check Risk mgmt
check Config mgmt
 
check Ensure that the plan[s] is up to date and still applicable.
 
check Changes in staff, stakeholders or institutions, construction, or vendor that may have occurred between the time of the original development and the deployment of these elements.
check Vendor defects
 

Update of the Deployment Plan and Integration Plans. Construction risks were low and no changes to the designs needed. The system can be configured to accommodate the additional signs. Vendor has good internal processes. The sign is his standard product.

Development of a Concept of Operations and Validation Plan

None

     

Reuse of the Validation Plan

Development of System Level Requirements and Verification Plans

None

   

 

Reuse of the Verification Plan

Development of High Level Design/Sub-system Requirements and Verification Plans

None

     

Reuse of the Verification Plan

Development of Component Level Design

None

     

COTS product

Hardware/Software Development

None –

Low

check Technical Review
 
check That the host configuration software is operational and can accommodate the additional signs
 
check Software was not checked out in the original implementation for additional signs
 

COTS product

Original design and implementation included the additional signs

Unit verification

None

     

Vendor performed

Unit Integration

None

     

Vendor performed

Sub-system verification

Low

check Technical Review
 
check Verify that controller, signs, and communications are working
 
check Defective signs, controller, communications or interface.
 

Signs and interfaces were checked out and verified at the factory, review of verification data

Sub-system Integration

Low

check Technical Review
 
check Coordination of integration activities, integration of controller with communications
check Integration of signs and controller
check Controller is integrated and working with communications
check Integration of signs and controllers
 

Use of the same interfaces that were used before. Integration issues will only occur if defects occur in manufacturing of the signs.

System verification

Medium

check Technical Review
 
check Verify that the host software is configured properly and all functionality is verified on all signs. [Regression] testing on the initial signs may be needed
 
check The added signs, or exercising the host software, uncovered a defect that was not known at time of initial integration and verification
 

Re-use of original acceptance Verification Plans – 30 signs to verify

Deployment

Medium

check Technical Review
 
check How the signs will be deployed
check The resources needed
check Normal construction issues
 
check Deployment in a timely manner
check Lack of resources to deploy the 30 signs.
 

Per the Deployment Plan

Validation

None

     

Validation on original project

Operations & Maintenance

Low

  • Conf. Mgt.
  • Synchronize the new system configuration with any updates to software, patches, user manuals, and fixes with documentation
  • Loss of the alignment of the documentation with the physical configuration of the system will provide a loss in system integrity.

Update user's manuals, as-builds, and software documentation if needed.

 

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