Lab Session 11: End course project preparation

Date: 25. November 2010

Duration of activity: 4 hours

Group members participating : Michaël Ludmann, Guillaume Depoyant, Anders Dyhrberg, Michal Owsinski.

I. A project we want do to?

I.a Uni Ball Vehicle
General Description:
A car similar to the LegWay project, but only having one ball as a wheel instead of regular wheels [1]. 


Hardware Required:
Only one NXT is required.

Sensors and actuators:
Three motors are required, and accelerometer and tilt sensors i various configurations.
- A special wheel with at specific size and rubber coating will be required for the right traction and system response.


Communication:
No PC program or communication is required.


Key Issues:
- The will only be one NXT brick and one embedded SW for this project. The main complexities for this project will be regarding the mechanical structure of the robot. Getting the right wheel, and figuring out what the right wheel would be. And figuring out the physics of the robot and designing, what most likely would be a quite complicated PID algorithm for balance.

I.b Alarm Dispatch Central

General Description:

We will build a small city, and an alarm dispatch central to help lego people in distress. N citizens are driving randomly around the city, following LEGO roads, while looking for LEGO people in distress. The map of the city is known by the central (i.e. the PC) and when a citizen detects a LEGO person it reports the coordinates to the alarm dispatch central. Then the central sends an ambulance using the shortest path based on the known map. The ambulance is self-driving, without further help.

The concept could be extended with different situations leading to different dispatch units like police cars, fire fighters, etc.

This idea could actually lead to a simulation of a real-world situation.

Hardware Required:

• Minimum 2 NXT bricks with an option to include many more. 
• One for an ambulance, that can go and rescue lego men 
• One for a citizen that can detect a lego man that have had an accident.

Sensors and actuators:

• Ambulance:
• 2x motors
• Ultrasonic sensor
• Touch sensor (to avoid collision)
• Sound and light
• Citizen:
• 2x motors
• Ultra sensor
• Touch sensor (to avoid collision)
• Sound and light
• Color sensor and or sound to detect citizen in distress.

Communication:

- A PC program is used. This is the alarm dispatch central which registers the emergency call from the citizen and dispatch the ambulance. Both communication with the PC using Bluetooth.

Key Issues:

• We need to implement a model of the city in the Dispatch Unit (PC)
• Citizens need to follow the roads
• Citizens need to detect the Lego Person in distress (using color sensor, will limit other colors not to be present during while scenario is running)
• The citizens need to avoid running into the ambulance (task priority)
• The ambulance need to follow roads base on a pre decided path (will require autonomus adjusting base on an pre decided plan)
• We need to implement a shortest path algorithem base on the reported coordinates and the layout of the city.
• Generally there is so many exceptions that could occur in this project, that we would need to decide on the key parts of this system that we want to address in order to reach the goal.

I.c Anti-terrorists game

General Description:
A simple game with two human players, each controlling one NXT. One is the terrorist who has to place a bomb in the game field, while the other is the counter-terrorist unit trying to locate and defuse the bomb before the time expires.

Players cannot see the playfield but only what their robot see through the camera mounted one the car.

Hardware Required:

• Minimum 3 NXT bricks with an option to include many more. 
• 1x for the terrorist unit
• 1x for the counter terrorist unit
• 1x NXT for the bomb
• 1x infrared ball for the bomb
• 2x computers, one for each player
• 2x games controllers (Xbox or Playstation pads)
• 2x Android Phones

Sensors and actuators:

• Terrorist:
• 3x motors (2 wheels, one arm to release the bomb)
• 1x camera, ultrasound/touch sensor for collision detection
• CTU: 
• 3x motors (2 wheels, one arm)
• 1x camera
• 1x infrared sensor (to detect the ball),
• 1x ultrasound and/or touch sensor (for collision detection)
• Bomb:
• 1x touch sensor (to detect when the infrared ball on top of the NXT bomb has fallen)

Communication:

Two communication forms will be required.

• Each unit will be connected to a PC during the entire game (hence 2 pc's required). The communication is based on bluetooth, and is used for sending instructions from the GamePad to the Robots, controlling the actuators.
• The mobile phones will be connected to pc's streaming their video using a Wireless Ethernet connection. 

Key Issues:

• To deal with streaming the camera images to the computers while displaying informations about the sensors readings on players screens and allowing them to control the robots in real time. (Will require dedicated SW for the Android Phones)
• We need to implement a GamePad driver for the PC to control the units. (This is fairly easily achieved using key mapping on the PC. Mapping GamePad press to Keyboard Press)
• The mechanical release of the BOMB from the terrorist unit could turn out to be problematic. Same could the for the deactivation mechanized used by the CTU.
• We would have to experiment with the game play in order to keep it balanced, and fun for all players.
• We have to make a program for the PC side to show the Video Stream from the robots.
• We need to find/design a god play field for the game. We currently are expecting to use a city model available to us, used for tank strategy game[2].
• (Optional control feature) An obvious extension to the game would be to use the Wireless Ethernet on the camera phones to control the robot, by forward the instructions from to NXT using bluetooth, in order to extend the range from theoreticaly 10m  to 100m. 

II. Project Decision and Workplan

Postponed until next session after our evaluation with Ole Caprani.

V. References
[1] http://spectrum.ieee.org/automaton/robotics/robotics-software/042910-a-robot-that-balances-on-a-ball
[2] http://www.rezultat.dk/UNDERHOLDNING/BATTLESTATION/spiltyper.htm