SEG4110 UML Design Assignment- Traffic Monitor and Simulation System

Create a system with the following requirements.

The purpose of this system is to allow a municipality to model the traffic flows in a network of streets. The system is used in three phases. In the first phase, the traffic engineers model the actual road network. In the second phase, they install cameras and observe the actual flow of vehicles through the network, recording this data for later playback. In the third phase they make modifications to the modelled road network, and then use the recorded vehicle data to simulate flows of vehicles over the modified roads, in order to see if their improvements would make a difference (in terms of reducing delays)

For the purposes of your project, you cannot set up cameras and watch traffic, so you will simulate the data about actual traffic.

The road network to be modelled includes the following elements: A roadway is made up of directional-segments connected by nodes. A directional-segment consists of a set of lanes, in which traffic flows in one direction. A normal two-lane road, has two single--lane directional-segments, flowing in opposite directions.

A directional segment has a length, a speed limit, a start point (a GPS coordinate) an an end-point (a GPS coordinate). Each lane can have one or more neighbouring lanes that vehicles move into or come from. A directional segment can also have a driveway count and a driveway business indicator. These are used in simulation to control how frequently vehicles enter and exit the segment from driveways along its side (or parking spots).

A node can be an intersection, a network entry point, a network exit point, or a segment state change point.

A network entry point is simply a place where vehicles 'magically' enter the system from outside (i.e. beyond the network of roads being modelled). When simulating the network, you will have to create imaginary vehicles to enter at these points. A network exit point is similar, except it is where traffic passes out of the network being simulated. Note that imaginary vehicles can also enter and exit at driveways.

A segment state change point is where two directional segments join, but some property of the segments differs. For example, the speed limit changes, the driveway intensity changes, the number of lanes changes etc.

An intersection is where more than two directional-segments are joined, so that traffic can flow from lanes in one segment to lanes in another. An intersection has a traversal time, the average amount of time it takes traffic to get across the intersection.

Whenever traffic can flow from one set of lanes to another set (at an intersection or segment state change point) this is recorded as follows: Each lane has a set of outgoing lanes, and a set of incoming lanes.

The data recorded from the cameras is processed and recorded as follows: Each vehicle flow has the following information: The vehicle's length and series of vehicle-node-encounters. Each vehicle-node-encounter records the node, the time the vehicle arrived at the node, the time the vehicle left the node, the lane the vehicle came from (or null meaning from outside the network) and the lane the vehicle moved to (or null if it moved outside the system). A vehicle is said to arrive at a node when it arrives at at a traffic jam, waiting to get through the node. When vehicles enter or exit from driveways, this is also recorded, but only at the first node at which the vehicle is 'noticed'; this is because the cameras only watch the nodes, not all along each segment.-

The system should be able to calculate data about total stop delay (the amount of time spent waiting in traffic jams), total delay (amount of time that vehicles spent going lower than the speed limit, or intersection traversal time), and other similar data.

For the purposes of this project you don't have to create a graphical view of the traffic, but you should be able to 'play back' the movements of vehicles, printing out a line of information as a vehicle moves through a node. You should also be able to print out textually details about each element and each vehicle. You are also not required to create the component of the system whereby the engineers add lanes, or improve intersections to see if this can redice delay, however, model your system assuming that this would be the next phase of development.

Additional details are up to you. You may discover that the above requirements are unsatisfactory. If so, explain any changes you had to make.

Last update to this page: Tuesday, 02-Aug-2011 17:43:11 EDT