Revision 1997
Added auto-calibration for barcode reading.
| trunk/code/projects/linefollowing/lineFollow.h | ||
|---|---|---|
| 21 | 21 |
#define MAX_DURATION 20 |
| 22 | 22 |
//! Number of consecutive white barcode readings before a barcode reset. |
| 23 | 23 |
#define TIMEOUT_DURATION 1000 |
| 24 |
//! Anything lower than this value is white |
|
| 25 |
#define GREY_THRESHOLD 500 |
|
| 26 |
//! Anything higher than this value is black |
|
| 27 |
#define BLACK_THRESHOLD 750 |
|
| 28 | 24 |
|
| 29 | 25 |
#define NUM_READINGS 20 |
| 30 | 26 |
|
| trunk/code/projects/linefollowing/main.c | ||
|---|---|---|
| 40 | 40 |
usb_putc(13); |
| 41 | 41 |
}*/ |
| 42 | 42 |
|
| 43 |
int barCode; |
|
| 44 | 43 |
while(1) |
| 45 | 44 |
{
|
| 46 |
|
|
| 47 | 45 |
int barcode = lineFollow(190); |
| 48 | 46 |
|
| 49 | 47 |
if(barcode != NOBARCODE && barcode != LINELOST) |
| trunk/code/projects/linefollowing/lineFollow.c | ||
|---|---|---|
| 23 | 23 |
* 1 - print out buckets |
| 24 | 24 |
* 2 - print out line sensor readings |
| 25 | 25 |
*/ |
| 26 |
#define DBG_LINEFOLLOW 0
|
|
| 26 |
#define DBG_LINEFOLLOW 2
|
|
| 27 | 27 |
|
| 28 |
//! Anything lower than this value is white |
|
| 29 |
int GREY_THRESHOLD = 300; |
|
| 30 |
//! Anything higher than this value is black |
|
| 31 |
int BLACK_THRESHOLD = 750; |
|
| 32 |
|
|
| 28 | 33 |
int countHi = 0; |
| 29 | 34 |
int countLo = 0; |
| 30 | 35 |
int maxAvg, avg; |
| ... | ... | |
| 53 | 58 |
|
| 54 | 59 |
void lineFollow_init() |
| 55 | 60 |
{
|
| 56 |
int i, j; |
|
| 61 |
int i, j, curReading; |
|
| 62 |
int lowGrey = 1000, highGrey = 0, lowBlack = 1000, |
|
| 63 |
highBlack = 0; |
|
| 57 | 64 |
|
| 58 | 65 |
analog_init(0); |
| 59 | 66 |
encoders_init(); |
| ... | ... | |
| 69 | 76 |
} |
| 70 | 77 |
isReset[i] = 1; |
| 71 | 78 |
} |
| 79 |
|
|
| 80 |
// Calibrate thresholds |
|
| 81 |
orb_set_color(YELLOW); |
|
| 82 |
delay_ms(2000); |
|
| 72 | 83 |
|
| 84 |
orb_set_color(BLUE); |
|
| 85 |
|
|
| 86 |
for(i=0; i<100; i++) |
|
| 87 |
{
|
|
| 88 |
curReading = read_line(LEFT_SENSOR + 6); |
|
| 89 |
if(curReading < lowGrey) |
|
| 90 |
lowGrey = curReading; |
|
| 91 |
if(curReading > highGrey) |
|
| 92 |
highGrey = curReading; |
|
| 93 |
|
|
| 94 |
delay_ms(20); |
|
| 95 |
} |
|
| 96 |
|
|
| 97 |
orb_set_color(YELLOW); |
|
| 98 |
delay_ms(2000); |
|
| 99 |
|
|
| 100 |
orb_set_color(GREEN); |
|
| 101 |
|
|
| 102 |
for(i=0; i<100; i++) |
|
| 103 |
{
|
|
| 104 |
curReading = read_line(LEFT_SENSOR + 6); |
|
| 105 |
if(curReading < lowBlack) |
|
| 106 |
lowBlack = curReading; |
|
| 107 |
if(curReading > highBlack) |
|
| 108 |
highBlack = curReading; |
|
| 109 |
|
|
| 110 |
delay_ms(20); |
|
| 111 |
} |
|
| 112 |
|
|
| 113 |
orbs_set(0,0,0,0,0,0); |
|
| 114 |
|
|
| 115 |
GREY_THRESHOLD = lowGrey / 2; |
|
| 116 |
BLACK_THRESHOLD = (highGrey + lowBlack) / 2; |
|
| 117 |
|
|
| 118 |
usb_puts("Grey: ");
|
|
| 119 |
usb_puti(lowGrey); |
|
| 120 |
usb_puts(", ");
|
|
| 121 |
usb_puti(highGrey); |
|
| 122 |
usb_puts("\nBlack: ");
|
|
| 123 |
usb_puti(lowBlack); |
|
| 124 |
usb_puts(", ");
|
|
| 125 |
usb_puti(highBlack); |
|
| 126 |
usb_puts("\nThresholds: ");
|
|
| 127 |
usb_puti(GREY_THRESHOLD); |
|
| 128 |
usb_puts(", ");
|
|
| 129 |
usb_puti(BLACK_THRESHOLD); |
|
| 130 |
usb_puts("\n\n");
|
|
| 131 |
|
|
| 132 |
delay_ms(1500); |
|
| 133 |
|
|
| 73 | 134 |
//numLast = { {0, 0, 0, NUM_READINGS}, {0, 0, 0, NUM_READINGS} };
|
| 74 | 135 |
} |
| 75 | 136 |
|
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