Intersection Safety Camera System

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Intersection Safety Camera System

• The OOtumlia Police Service has contracted you to
  develop software for controlling their
  Intersection Safety Camera System. All the
  hardware is already available high speed
  cameras, sensors buried beneath the roadway,
  computer equipment (controller), hard disk
  storage devices, time and date device, and an
  internal computer Ethernet network connecting
  each traffic light site to the central office
  database, which is located near City Hall.

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Intersection Safety Camera System
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Intersection Safety Camera System

• How the Intersection Safety Camera Works
• The intersection safety camera is usually located
  about 20 meters back from the intersection. This
  is to allow the photographs to be taken of the
  rear of the vehicle that is violating the red
  light. The camera is connected to the traffic
  signal control box and to two sensors buried in
  the roadway. One sensor is installed near the
  stop line, and the second sensor is about two
  meters back from the first.

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Intersection Safety Camera System

• How the Intersection Safety Camera Works
• When the light turns red, the sensors become
  active. A vehicle travelling over the sensor
  triggers the camera unit and two photographs are
  taken. The first picture is of the vehicle
  outside the intersection during the red phase.
  The picture will show that the traffic light is
  red. The second picture shows the vehicle
  actually in the intersection and must show that
  the light is still red for an offence to have
  been committed.

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Intersection Safety Camera System

• During the red phase, the camera must take the
  first picture within 0.1 ms of a car crossing the
  first sensor, and the second picture must be
  taken before 0.1 ms after the car has crossed the
  second sensor.
• Traffic light photos are required to be stored in
  the central database. However, a backup of the
  photos should be maintained at the traffic light
  site.

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Intersection Safety Camera System

• Draw a UML architecture (component) diagram model
  of your design for the above system.
• Draw a UML deployment diagram to indicate which
  components are co-located.
• Identify a particular software architecture (from
  textbook section 9.6) that resembles your design,
  and provide justification for its use, i.e.,
  explain why it is appropriate to use it.

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Intersection Safety Camera System

• Draw a UML class diagram of your design for the
  sensors, cameras, and controller at the traffic
  camera site. Assume all your components
  interface through software.
• Identify any item (i.e. Interfaces) in your
  system that you have designed for re-use by
  someone else in another system.
• Identify any re-usable technology that you have
  re-used in your system.

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Intersection Safety Camera System

• Draw a UML Sequence Diagram showing the actors
  (offending vehicle), objects and messages
  involved in the capture of a violator.
• Draw a UML State Diagram describing the states,
  state transitions, events, and actions involved
  in capturing a violator.