A real time shooting based survival game in which each player is for himself. Each player is equipped with a laser gun, a magazine full of ten bullets and a task to reach the centralized server that is continuously monitoring the entire game. The server may reward or penalize the player depending upon her/his performance and creates bombs to make the game more difficult and tricky.
Salient Features
- Centralized System : The game revolves around Raspberry Pi2 and which at any point of time, knows every attribute of each player and is the ultimate target to reach.
- Wireless Communication : Use of Xbee and Radio Frequencies to trigger Wireless communication and exchange of critical information is a key aspect of the game.
- Real-time Display : All critical information like the health, bullet count etc. are displayed using a LCD monitor, given to each player.
- Innovative Bullet Count : A reflection based shooting mechanism is incorporated to keep an accurate track of bullets of each player.
- Unpredictable gameplay : Pi controls the game, and randomly generates Mines, Health and Armour packets, thereby making it different every time.
Components Used :
Raspberry Pi2 LCD Display
Arduino Mega Light Dependent Resistors
Arduino Base Shield Grove LED Bars
Xbee Shield Buzzer
Xbee S1 Laser
Xbee Dongle LED
BLE Beacon
Softwares Used :
Arduino IDE
https://www.arduino.cc/en/Main/Software
XCTU for Xbee Configuration
https://www.digi.com/products/xbee-rf-solutions/xctu-software/xctu
Python - for the script on the Raspberry Pi
Each player was given a laser gun and a circuit to keep count of the shots fired from the laser. The Circuit consisted of a Light Dependent Resistor (LDR) in series with a normal ohmic resistor. Entire circuit was given 5V and potential across LDR was measured.
Since Laser is a very high intensity source, potential across LDR saw a quick increase from its previous value. This difference was measured and used to keep track of the bullets consumed.
Hardware Used: a.) Laser
b.) Light Dependent Resistor
c.) Led Bar to show player available bullets
Multiple LDRs were soldered in parallel to create a grid of light sensitive sensors such that, whenever laser fell on any one of them a spike in potential drop was observed detecting a hit.
An LED bar was used to show player (in real-time) her/his health. Alongside this was a buzzer that rang whenever hit. A long buzzer indicated that player is out of health.
Health Reduced due to:
a.) Bomb – Health was reduced by a 20 whenever player came close to a mine planted by the centralized server to prevent player from reaching it.
b.) Head-Shot – A major damage of 50 points is incurred whenever an opponent is able to hit a shot directly on the head. Since head is the most sensitive spot, a shot there results in maximum damage.
c.) Chest Shot – A normal damage of 10 points whenever any other sensor is hit if Armour is 0.
Library Link: https://github.com/Seeed-Studio/Grove_LED_Bar
- An LCD Bar was also used to display Health and Armour.
- The Armour will decrease whenever there is a chest shot but not when there is head shot.
- Also every 100 sec you will be rewarded with full Armour if you are alive till then while your health will remain same.
- There is Timer in the LCD Display itself that will count the time. Your health will not be affected if you have greater than 0 Armour unless it is a head shot.
It uses I2C as communication method with microcontroller for the display.
Library used: LiquidCrystal.h
//Initialize the library with number of interface pins LiquidCrystal lcd(12, 7, 6, 25, 24, 23, 22)
Some of the LiquidCrystal library function used were LiquidCrystal. begin (x,y); // set up the LCD's number of x columns and y rows:
LiquidCrystal. setCursor (x,y); //s et the cursor to column x, line y
LiquidCrystal. print (message); // prints the message on lcd display
LiquidCrystal. clear (); // Clear screen
Useful Link: https://www.arduino.cc/en/Tutorial/HelloWorld
Library Used: https://www.arduino.cc/en/Reference/LiquidCrystal
A network of XBees was created to ensure proper data transfer and game synchronization between each player and the centralized server.
Each Arduino had an Xbee shield and one Xbee that, was capable of sending and receiving data to the raspberry pi2. Raspberry pi2 had an Xbee dongle that enabled it to communicate using Serial libraries of python.
All Xbee were configured to communicate on Channel ‘C’ and were given a PAN ID of 1111. Each Xbee on Arduino had their DL as the address of the Xbee on pi. Xbee pi on the other had was able to send data to every other Xbee using its python library.
Pi used to receive data in the form of a Json Object that contains source info and data, making it easy for pi to classify data based on source. Strings contained particular tokens that helped pi decide necessary actions required. Script was written in such a way that pi knew every small thing that was happening in the game and hence updates were made in real-time.
Hm 10 BLE beacons were used to approximate the distance of each player from the server. The beacons were Bluetooth 4. beacons and RSSI value of signals was used to approximate the distance.
The beacon on pi was set to iBeacon mode using AT commands. Below are the AT commands used for the project:
AT AT+RESET AT+IMME AT+ROLE AT+IBEA AT+DISC? AT+DISI?
Every Arduino had a Beacon that, using DISI command and the address of that particular beacon finds the RSSI value or the percentage signal strength value, that is used to approximate the distance.
The knowledge of inter player distance allowed Pi to plot bombs and random health packages, making the game a more interesting and tricky!
Datasheet Link: http://fab.cba.mit.edu/classes/863.15/doc/tutorials/programming/blueto oth/bluetooth40_en.pdf
The centralized server we have been saying so far is nothing but raspberry pi. A python Script is run in Pi that contains a Class called Player. Each player has bullets, health and distance from server as parameters.
Pi has a Xbee dongle that receives the data from players and updates the parameters accordingly. Alongside this, pi also has a Beacon set in iBeacon mode to allow other beacons (on player arduino) to calculate approximate distance, allowing it to plant bombs in the game.
The bombs appear in circles as mine fields, they randomly appear for a particular time and inflicts a damage of 20 units to the person close to it.
Whenever a shot if fired of a player is hit, pi knows and accordingly makes the necessary updates, thereby being up-to-date all through the game.
A player wins the game if he is the first one to reach the pi.
Useful Link: https://github.com/nioinnovation/python-xbee
Follow the following points one by one to assemble all the hardware properly as per the declaration on the code.
1.) Each Arduino has two shields, placed one above the other:
a.) A Xbee Shield with a Xbee on it.
b.) A base Shield for other Sensors
2.) Put Health LED bar on D4 of the base Shield
3.) Put Bullet LED bar on D8 of the base Shield
4.) Put Buzzer on A0 of the base Shield
5.) Laser gun and Shooting targets ground will go to the ground or Arduino
6.) Power Laser Gun, and Shooting targets with 5V Vcc
7.) Put the third end of Laser Gun to A
8.) Put the third end of Targets to A5 and for head-shot A3.
9.) Beacon on each Arduino will be powered with 3.3 V and ground will be same as Arduino ground.
10.) Tx of Beacon will go to slot 19 (Rx1) and Rx of Beacon will go to slot 18(Tx1).
**This Being a Real-time outdoor game , it can be played anywhere you want. The world is your stage here. Although care should be taken as external power needs to be given to drive each Arduino board and corresponding sensors.
Due to internal reasons Python script for Raspberry Pi2 is not shared
Group consists of:
a.) Paritosh Mittal
b.) Mudit Agarwal
c.) Manoj Ghuhan A
d.) Kevin Pandya