1.File: C:\Program Files\Robotics Academy\RobotC\sample programs\RCX\arushi\robot_
/////////////////////////////////////////////////////////////////////////
//
// This is the Program to control the Robot Head
// Program By: Arushi Raghuvanshi
// Date: Oct 2006
//
/////////////////////////////////////////////////////////////////////////
// Define the sensor constants to use later in the program for readability
const tSensors touchSensor = (tSensors) S2; //touch Sensor
const tSensors leftLightSensor = (tSensors) S3; //light sensor
const tSensors rightLightSensor = (tSensors) S1; //light sensor
// Define Global Variables for use in the program
int M[4][4]; // This is the 4x4 matrix for the gate
int iState[4]; // This is 4x1 matrix for the input state
int oState[4]; // This is 4x1 matrix for the output state
bool a, b; // a and b are two inputs, mapped to some combination of sen
bool P, Q; // P and Q are two outputs, mapped to some combination of mo
void setMatrixM()
{
// Initialize the matrix for the gate
// The program behavior changes just by changing this matrix
// This matrix here is a simple identity matrix
// implying that inputs are directly connected to outputs
M[0][0] = 1; M[0][1] = 0; M[0][2] = 0; M[0][3] = 0;
M[1][0] = 0; M[1][1] = 1; M[1][2] = 0; M[1][3] = 0;
M[2][0] = 0; M[2][1] = 0; M[2][2] = 1; M[2][3] = 0;
M[3][0] = 0; M[3][1] = 0; M[3][2] = 0; M[3][3] = 1;
}
void setInputState()
{
// Initialize the input matrix, by looking at the input variables a and b
iState[0] = !a & !b; //00
iState[1] = !a & b; //01
iState[2] = a & !b; //10
iState[3] = a & b; //11
}
void multiplyMatrix()
{
// do the regular matrix multiplation of M with iState to get matrix oState
int i, j;
for (i=0; i<4; i++)
{
oState[i] = 0;
for (j=0; j<4; j++)
{
oState[i] = oState[i] + (M[i][j] * iState[j]);
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2.File: C:\Program Files\Robotics Academy\RobotC\sample programs\RCX\arushi\robot_
}
// if the value is negative, set it to positive, since sign is lost in
// measurement of quantum gate output
if (oState[i] < 0)
oState[i] = oState[i] * (-1);
}
}
void interpretOutputState()
{
// interpret oState matrix in terms of P and Q actions
int total=0;
int i=0;
int oneCounter=0;
int x=0;
// First reset P & Q
P = false;
Q = false;
// first count how many ones
total = oState[0] + oState[1] + oState[2] + oState[3];
// probablity of each '1's in the matrix is equally randomized
// following routine returs a number from 0 to total-1
// so if the total # of ones are 2, then the following routine
// returns either 0 or 1, with equal probability
if (total > 1 )
x = random(total-1);
else
x = 0;
// Now out of the oState entries that have a value of '1', we pick
// an the entry based on the random value above
for (i=0; i<4; i++)
{
if (oState[i] != 0)
{
if (x == oneCounter)
{
// set the action flags, use the value of i to calculate P and Q
switch (i)
{
case 0 : P = false; Q = false; break;
case 1 : P = false; Q = true; break;
case 2 : P = true; Q = false; break;
case 3 : P = true; Q = true; break;
}
// the above switch/case can also be replaced with following two state
// P = (bool) i/2;
// Q = (bool) i%2;
break; // got a match, break out of for loop
}
oneCounter++;
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3.File: C:\Program Files\Robotics Academy\RobotC\sample programs\RCX\arushi\robot_
}
}
}
// Following two routines are the only routines that are specific to
// a particular robot design
void executeAction()
{
// P and Q are either true or false based on output matrix
// This routine translates P and Q into motor actions
// Port A is attached to base motor, rotates the head, can move at normal spee
// Port B has two motors attached, moves both eyebrows - needs to move at low
// Port C has 3 motors attached - moves 2 eyes and mouth -
// This needs to move at low power, and also need to move back & fo
// so has to know previous state
if (P)
{
// turn the head right, wait a while, and turn it back straight
motor[motorA] = 100; wait1Msec(700);
motor[motorA] = -100; wait1Msec(700); motor[motorA] = 0;
}
else
{
// do not rotate the head
motor[motorA] = 0;
}
if (Q)
{
// Move eyebrows back and forth
motor[motorB] = 15; wait1Msec(250);
motor[motorB] = -15; wait1Msec(100); motor[motorB] = 0;
// Move eyes and mouth, and come back to normal position
motor[motorC] = 30; wait1Msec(500);
motor[motorC] = -30; wait1Msec(500); motor[motorA] = 0;
}
else
{
// do not change any facial expressions
motor[motorB] = 0;
motor[motorC] = 0;
}
}
void checkSensors()
{
// This routine checks the value of sensors and sets the variables a and b
// Check for a significant difference (10%) between left light sensor and righ
// To test, shine a flashlight in front of left sensor
if (SensorValue(leftLightSensor) > (SensorValue(rightLightSensor)+10))
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4.File: C:\Program Files\Robotics Academy\RobotC\sample programs\RCX\arushi\robot_
a = true;
else
a = false;
// Check if either of the touch sensors are pressed
// Both touch sensors are attached to same port and are OR'ed
if (SensorValue(touchSensor) == 1 )
b = true;
else
b = false;
ClearSensorValue(leftLightSensor);
ClearSensorValue(rightLightSensor);
ClearSensorValue(touchSensor);
}
// This is the main program
task main()
{
// Initialize sensor types, connected to three ports
SetSensorType(leftLightSensor, sensorReflection);
SetSensorType(rightLightSensor, sensorReflection);
SetSensorType(touchSensor, sensorTouch);
// Clear all sensors
ClearSensorValue(leftLightSensor);
ClearSensorValue(rightLightSensor);
ClearSensorValue(touchSensor);
// Initialize all motors to 0 - stopped
motor[motorA] = 0;
motor[motorB] = 0;
motor[motorC] = 0;
// Set the matrix for the gate
setMatrixM();
while (true)
{
PlayTone(220, 10); //debugging tool - Plays a 220hz tone for 1 second
wait1Msec(1000); //wait 5 seconds before next cycle
checkSensors(); //Check Sensors and set input variables
setInputState(); //Create input matrix
multiplyMatrix(); //Compute output matrix
interpretOutputState(); //Determine what actions to do
executeAction(); //Execute those actions
PlayTone(990, 50); //debugging tool - Plays a 330hz tone for 1 second
wait1Msec(3000); //wait 5 seconds before next cycle
}
}
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