root / trunk / code / projects / linefollowing / lineFollow.c @ 1842
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#include "lineFollow.h" |
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#define NOBARCODE -2 |
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#define CODESIZE 2 |
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int countHi = 0; |
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int countLo = 0; |
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int maxAvg, avg;
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int barCode[ CODESIZE ];
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int barCodePosition=0; |
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void lineFollow_init()
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{ |
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analog_init(0);
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lost = 0;
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} |
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int lineFollow()
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{ |
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int colors[6]; |
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int position;
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updateLine(colors); |
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position = lineLocate(colors); |
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//not on line
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if(position == NOLINE)
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{ |
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if(lost++>20) |
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{ |
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orb2_set_color(GREEN); |
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motors_off(); |
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return LINELOST;
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} |
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} |
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//on line
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else
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{ |
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position*=30;
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orb2_set_color(ORB_OFF); |
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motorLeft(min(SPEED+position, 255));
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motorRight(min(SPEED-position, 255));
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lost=0;
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} |
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updateBarCode(); |
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return getBarCode();
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} |
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int getBarCode(){
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if(barCodePosition!=CODESIZE) return NOBARCODE ; |
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int temp = 0; |
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int i;
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for(i=0; i<CODESIZE; i++) |
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temp += (barCode[i] << i); |
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barCodePosition = 0;
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return temp;
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} |
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void updateLine(int* values) |
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{ |
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for(int i = 0; i<5; i++) |
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values[i] = assignColor(i, updateIR(i)); |
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} |
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int updateIR(int n) |
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{ |
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//maps the sensors to the analog input ports
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int ports[5] = {13, 12, 3, 2, 9}; |
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return analog_get10(ports[n]);
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} |
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int assignColor(int port, int analog) |
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{ |
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if (analog < 150) |
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return WHITE;
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else
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return BLACK;
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} |
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int lineLocate(int* colors) |
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{ |
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int i;
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int wsum = 0; |
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int count=0; |
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for(i = 0; i<5; i++) |
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{ |
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count+=(colors[i]+1)/2; |
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wsum += (i)*colors[i]; |
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} |
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if(count==0) |
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return NOLINE;
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return (wsum/count)-4; |
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} |
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void updateBarCode()
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{ |
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//maps the sensors to the analog input ports
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int ports[2] = {8,1}; |
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int current[2]; |
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// current[0] = analog_get10(8);
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current[1] = analog_get10(1); |
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// usb_puti(analog_get10(8));
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// usb_putc('\t');
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usb_puti(analog_get10(1));
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usb_putc('\n');
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if(current[1]>500) |
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{ |
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if(countHi++==0) |
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{ |
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avg = 500;
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maxAvg = 500;
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} |
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else
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{ |
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avg = 3*avg + current[1]; |
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avg/=4;
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maxAvg = max(maxAvg, avg); |
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} |
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} |
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else if(countHi>10) |
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{ |
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if(countLo++>15) |
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{ |
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countHi=countLo=0;
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// if(maxAvg>825)orb1_set_color(RED);
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// else orb1_set_color(BLUE);
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barCode[barCodePosition++] = (maxAvg > 825 ? 2:1)-1; |
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} |
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} |
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else countHi/=2; |
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if(countHi==0)countLo=0; |
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} |
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int min(int x, int y){return x>y ? y : x;} |
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int max(int x, int y){return x<y ? y : x;} |
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void motorLeft(int speed){ |
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speed-=127;
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if(speed>=0)motor_l_set(FORWARD, 160+speed*95/128); |
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else motor_l_set(BACKWARD, 160-speed*95/127); |
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} |
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void motorRight(int speed){ |
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speed-=127;
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if(speed>=0)motor_r_set(FORWARD, 160+speed*95/128); |
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else motor_r_set(BACKWARD, 160-speed*95/127); |
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} |
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