CS452 - Real-Time Programming - Spring 2011

Lecture 19 - Projects

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1. Exam
2. Broken trains

Milestones

1. Tracking & Route Finding

What you are expected to do

• One locomotive on the track:
  • Give the locomotive a destination & speed at the terminal.
    • `Destination' means `x cm past switch/sensor y, travelling in direction z'
    • The part of the train from which measurements are made is the track contact, which is attached to one of the trucks. (The original definition of a truck is a unit consisting of several wheels, which supports part of a vehicle. Each locomotive locomotive has two four wheel trucks; an eighteen wheel semi-trailer has three trucks, a two wheel truck at the front of the tractor, an eight wheel truck at the back of the tractor, and a second eight wheel truck at the back of the trailer.)
  • Your application knows where the train is at all times.
    • `Where the train is' means destination, as defined above, plus
    • direction and velocity of the train.
    • Important terminology
      • The velocity of a train is the rate at which it moves along the track, measured in centimetres/second. Velocity is normally signed, and the easiest way of doing the math is to make track segments directed
      • The speed of a train is the number written to the train controller when you change how fast the train is going.
      • The most important part of the first milestone is creating the ability to give a train a particular velocity by altering its speed. This is called having a calibration of the train.
  • Train finds the shortest route to the destination and travels to it.
• This should be robust against malfunctioning sensors and switches
• To do this you need
  • Calibration. Calibration is the primary goal of the first milestone.
  • Route creation. To get good performance in your complete project it is essential that your route-finding should include routes in which the train changes direction.
• It is possible to complete this assignment without achieving what you project needs simply by running the trains very slowly. We expect you to have the trains running fairly quickly -- speed 8 to 12 -- during the milestone demo.

2. Avoiding

What you are expected to do

• Two or three locomotives on the track:
  • Give each locomotive a destination & speed at the terminal.
  • They find non-conflicting routes to their destinations and travel to them.
  • Your application knows where the trains are at all times.
• This should be robust against malfunctioning sensors and switches
  • Locomotives should not collide
  • Locomotives should not fuse into one when they get too close together
• To do this you need
  • Adaptive route finding
  • A track reservation system

Projects

1. Train style

Give trains roles and objectives. For example,

• Passenger train travels on a repetitive route meeting a schedule.
• Freight train travels to random destinations as fast as possible.
• Objective is to deliver as much freight as possible while keeping a passenger train on time.

Another example,

• Trains are taxis.
• When a load appears they race to see if they can get it.

Another example,

• Trains are buses, which travel long routes from one place on the track to another.
• At the end of the route is a scheduled trip to a different location.
• When a bus is late arriving, the dispatcher must find another, unused bus to leave at the scheduled leaving time.

2. Game style: AI

The track is a graph.

• Several different ways to choose vertices and edges

Many games are played on graphs

• Checkers, snakes & ladders, maze games, etc.
• Implement a graph game played on the track graph.

For example, watchmen and bandit.

• One train is the bandit, which tries to move from one hide-out to another.
• The other trains are watchmen, who try to prevent the bandit from getting to a hide-out once he is out in the open.

Another example, PAC man

• One train tries to cover as much track as possible.
• Other trains try to trap him so that he can't get reservations that would allow him to keep moving.

3. Game style: interactive

In the games you play for pleasure, the user normally controls one or more of the game entities.

• the bandit
• the trapping trains

Students often want to make an interactive project. It has been done successfully in the past, but constructing a usable interface is a real challenge

Return to:

• Bill Cowan's lecture notes for CS452 in s11
• Bill Cowan's Spring 2011 CS452 page
• Bill Cowan's CS452 page
• Bill Cowan's teaching page
• Bill Cowan's home page