David's line following code from the LVBots competition, 2015.
Dependencies: GeneralDebouncer Pacer PololuEncoder mbed
Fork of DeadReckoning by
main.cpp@20:dbec34f0e76b, 2014-02-27 (annotated)
- Committer:
- DavidEGrayson
- Date:
- Thu Feb 27 19:46:35 2014 +0000
- Revision:
- 20:dbec34f0e76b
- Parent:
- 19:a11ffc903774
- Child:
- 21:c279c6a83671
Broke up driveHome into two functions.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
DavidEGrayson | 0:e77a0edb9878 | 1 | #include <mbed.h> |
DavidEGrayson | 8:78b1ff957cba | 2 | #include <Pacer.h> |
DavidEGrayson | 19:a11ffc903774 | 3 | #include <math.h> |
DavidEGrayson | 0:e77a0edb9878 | 4 | |
DavidEGrayson | 8:78b1ff957cba | 5 | #include "motors.h" |
DavidEGrayson | 8:78b1ff957cba | 6 | #include "encoders.h" |
DavidEGrayson | 9:9734347b5756 | 7 | #include "leds.h" |
DavidEGrayson | 8:78b1ff957cba | 8 | #include "pc_serial.h" |
DavidEGrayson | 9:9734347b5756 | 9 | #include "test.h" |
DavidEGrayson | 12:835a4d24ae3b | 10 | #include "reckoner.h" |
DavidEGrayson | 16:8eaa5bc2bdb1 | 11 | #include "buttons.h" |
DavidEGrayson | 0:e77a0edb9878 | 12 | |
DavidEGrayson | 10:e4dd36148539 | 13 | int __attribute__((noreturn)) main() |
DavidEGrayson | 2:968338353aef | 14 | { |
DavidEGrayson | 2:968338353aef | 15 | pc.baud(115200); |
DavidEGrayson | 2:968338353aef | 16 | |
DavidEGrayson | 2:968338353aef | 17 | // Enable pull-ups on encoder pins and give them a chance to settle. |
DavidEGrayson | 9:9734347b5756 | 18 | encodersInit(); |
DavidEGrayson | 9:9734347b5756 | 19 | motorsInit(); |
DavidEGrayson | 16:8eaa5bc2bdb1 | 20 | buttonsInit(); |
DavidEGrayson | 4:1b20a11765c8 | 21 | |
DavidEGrayson | 8:78b1ff957cba | 22 | // Test routines |
DavidEGrayson | 9:9734347b5756 | 23 | //testMotors(); |
DavidEGrayson | 10:e4dd36148539 | 24 | //testEncoders(); |
DavidEGrayson | 12:835a4d24ae3b | 25 | //testLineSensors(); |
DavidEGrayson | 16:8eaa5bc2bdb1 | 26 | //testReckoner(); |
DavidEGrayson | 17:2df9861f53ee | 27 | //testButtons(); |
DavidEGrayson | 20:dbec34f0e76b | 28 | //testDriveHome(); |
DavidEGrayson | 20:dbec34f0e76b | 29 | testFinalSettleIn(); |
DavidEGrayson | 2:968338353aef | 30 | |
DavidEGrayson | 4:1b20a11765c8 | 31 | while(1) |
DavidEGrayson | 4:1b20a11765c8 | 32 | { |
DavidEGrayson | 9:9734347b5756 | 33 | |
DavidEGrayson | 0:e77a0edb9878 | 34 | } |
DavidEGrayson | 0:e77a0edb9878 | 35 | } |
DavidEGrayson | 12:835a4d24ae3b | 36 | |
DavidEGrayson | 12:835a4d24ae3b | 37 | void updateReckonerFromEncoders() |
DavidEGrayson | 12:835a4d24ae3b | 38 | { |
DavidEGrayson | 12:835a4d24ae3b | 39 | while(encoderBuffer.hasEvents()) |
DavidEGrayson | 12:835a4d24ae3b | 40 | { |
DavidEGrayson | 12:835a4d24ae3b | 41 | PololuEncoderEvent event = encoderBuffer.readEvent(); |
DavidEGrayson | 12:835a4d24ae3b | 42 | switch(event) |
DavidEGrayson | 12:835a4d24ae3b | 43 | { |
DavidEGrayson | 17:2df9861f53ee | 44 | case ENCODER_LEFT | POLOLU_ENCODER_EVENT_INC: |
DavidEGrayson | 17:2df9861f53ee | 45 | reckoner.handleTickLeftForward(); |
DavidEGrayson | 17:2df9861f53ee | 46 | break; |
DavidEGrayson | 17:2df9861f53ee | 47 | case ENCODER_LEFT | POLOLU_ENCODER_EVENT_DEC: |
DavidEGrayson | 17:2df9861f53ee | 48 | reckoner.handleTickLeftBackward(); |
DavidEGrayson | 17:2df9861f53ee | 49 | break; |
DavidEGrayson | 17:2df9861f53ee | 50 | case ENCODER_RIGHT | POLOLU_ENCODER_EVENT_INC: |
DavidEGrayson | 17:2df9861f53ee | 51 | reckoner.handleTickRightForward(); |
DavidEGrayson | 17:2df9861f53ee | 52 | break; |
DavidEGrayson | 17:2df9861f53ee | 53 | case ENCODER_RIGHT | POLOLU_ENCODER_EVENT_DEC: |
DavidEGrayson | 17:2df9861f53ee | 54 | reckoner.handleTickRightBackward(); |
DavidEGrayson | 17:2df9861f53ee | 55 | break; |
DavidEGrayson | 12:835a4d24ae3b | 56 | } |
DavidEGrayson | 12:835a4d24ae3b | 57 | } |
DavidEGrayson | 12:835a4d24ae3b | 58 | } |
DavidEGrayson | 17:2df9861f53ee | 59 | |
DavidEGrayson | 19:a11ffc903774 | 60 | float magnitude() |
DavidEGrayson | 19:a11ffc903774 | 61 | { |
DavidEGrayson | 19:a11ffc903774 | 62 | return sqrt((float)reckoner.x * reckoner.x + (float)reckoner.y * reckoner.y); |
DavidEGrayson | 19:a11ffc903774 | 63 | } |
DavidEGrayson | 19:a11ffc903774 | 64 | |
DavidEGrayson | 20:dbec34f0e76b | 65 | float dotProduct() |
DavidEGrayson | 20:dbec34f0e76b | 66 | { |
DavidEGrayson | 20:dbec34f0e76b | 67 | float s = (float)reckoner.sin / (1 << 30); |
DavidEGrayson | 20:dbec34f0e76b | 68 | float c = (float)reckoner.cos / (1 << 30); |
DavidEGrayson | 20:dbec34f0e76b | 69 | float magn = magnitude(); |
DavidEGrayson | 20:dbec34f0e76b | 70 | if (magn == 0){ return 0; } |
DavidEGrayson | 20:dbec34f0e76b | 71 | return ((float)reckoner.x * c + (float)reckoner.y * s) / magn; |
DavidEGrayson | 20:dbec34f0e76b | 72 | } |
DavidEGrayson | 20:dbec34f0e76b | 73 | |
DavidEGrayson | 18:b65fbb795396 | 74 | // The closer this is to zero, the closer we are to pointing towards the home position. |
DavidEGrayson | 18:b65fbb795396 | 75 | // It is basically a cross product of the two vectors (x, y) and (cos, sin). |
DavidEGrayson | 19:a11ffc903774 | 76 | float determinant() |
DavidEGrayson | 18:b65fbb795396 | 77 | { |
DavidEGrayson | 18:b65fbb795396 | 78 | // TODO: get rid of the magic numbers here (i.e. 30) |
DavidEGrayson | 18:b65fbb795396 | 79 | float s = (float)reckoner.sin / (1 << 30); |
DavidEGrayson | 18:b65fbb795396 | 80 | float c = (float)reckoner.cos / (1 << 30); |
DavidEGrayson | 19:a11ffc903774 | 81 | return (reckoner.x * s - reckoner.y * c) / magnitude(); |
DavidEGrayson | 19:a11ffc903774 | 82 | } |
DavidEGrayson | 19:a11ffc903774 | 83 | |
DavidEGrayson | 19:a11ffc903774 | 84 | int16_t reduceSpeed(int16_t speed, int16_t reduction) |
DavidEGrayson | 19:a11ffc903774 | 85 | { |
DavidEGrayson | 19:a11ffc903774 | 86 | if (reduction > speed) |
DavidEGrayson | 19:a11ffc903774 | 87 | { |
DavidEGrayson | 19:a11ffc903774 | 88 | return 0; |
DavidEGrayson | 19:a11ffc903774 | 89 | } |
DavidEGrayson | 19:a11ffc903774 | 90 | else |
DavidEGrayson | 19:a11ffc903774 | 91 | { |
DavidEGrayson | 19:a11ffc903774 | 92 | return speed - reduction; |
DavidEGrayson | 19:a11ffc903774 | 93 | } |
DavidEGrayson | 18:b65fbb795396 | 94 | } |
DavidEGrayson | 18:b65fbb795396 | 95 | |
DavidEGrayson | 20:dbec34f0e76b | 96 | void driveHomeAlmost(); |
DavidEGrayson | 20:dbec34f0e76b | 97 | void finalSettleIn(); |
DavidEGrayson | 20:dbec34f0e76b | 98 | |
DavidEGrayson | 20:dbec34f0e76b | 99 | void driveHome() |
DavidEGrayson | 20:dbec34f0e76b | 100 | { |
DavidEGrayson | 20:dbec34f0e76b | 101 | driveHomeAlmost(); |
DavidEGrayson | 20:dbec34f0e76b | 102 | finalSettleIn(); |
DavidEGrayson | 20:dbec34f0e76b | 103 | } |
DavidEGrayson | 20:dbec34f0e76b | 104 | |
DavidEGrayson | 20:dbec34f0e76b | 105 | void driveHomeAlmost() |
DavidEGrayson | 18:b65fbb795396 | 106 | { |
DavidEGrayson | 18:b65fbb795396 | 107 | led1 = 1; led2 = 1; led3 = 0; led4 = 0; |
DavidEGrayson | 18:b65fbb795396 | 108 | |
DavidEGrayson | 18:b65fbb795396 | 109 | bool dir = false; |
DavidEGrayson | 18:b65fbb795396 | 110 | uint16_t transitions = 0; |
DavidEGrayson | 18:b65fbb795396 | 111 | Timer timer; |
DavidEGrayson | 18:b65fbb795396 | 112 | timer.start(); |
DavidEGrayson | 19:a11ffc903774 | 113 | |
DavidEGrayson | 19:a11ffc903774 | 114 | const int16_t maxSpeed = 300; |
DavidEGrayson | 19:a11ffc903774 | 115 | |
DavidEGrayson | 19:a11ffc903774 | 116 | while(1) |
DavidEGrayson | 18:b65fbb795396 | 117 | { |
DavidEGrayson | 18:b65fbb795396 | 118 | updateReckonerFromEncoders(); |
DavidEGrayson | 19:a11ffc903774 | 119 | |
DavidEGrayson | 19:a11ffc903774 | 120 | float magn = magnitude(); |
DavidEGrayson | 19:a11ffc903774 | 121 | |
DavidEGrayson | 19:a11ffc903774 | 122 | if (magn < (1<<17)) |
DavidEGrayson | 18:b65fbb795396 | 123 | { |
DavidEGrayson | 19:a11ffc903774 | 124 | // We are within 8 encoder ticks, so go to the next step. |
DavidEGrayson | 19:a11ffc903774 | 125 | break; |
DavidEGrayson | 19:a11ffc903774 | 126 | } |
DavidEGrayson | 19:a11ffc903774 | 127 | |
DavidEGrayson | 19:a11ffc903774 | 128 | float det = determinant(); |
DavidEGrayson | 19:a11ffc903774 | 129 | |
DavidEGrayson | 19:a11ffc903774 | 130 | { |
DavidEGrayson | 19:a11ffc903774 | 131 | bool nextDir = det > 0; |
DavidEGrayson | 18:b65fbb795396 | 132 | if (nextDir != dir) { transitions++; } |
DavidEGrayson | 18:b65fbb795396 | 133 | dir = nextDir; |
DavidEGrayson | 18:b65fbb795396 | 134 | } |
DavidEGrayson | 18:b65fbb795396 | 135 | |
DavidEGrayson | 19:a11ffc903774 | 136 | int16_t speedLeft = maxSpeed; |
DavidEGrayson | 19:a11ffc903774 | 137 | int16_t speedRight = maxSpeed; |
DavidEGrayson | 19:a11ffc903774 | 138 | if (magn < (1<<20)) // Within 64 encoder ticks of the origin, so slow down. |
DavidEGrayson | 18:b65fbb795396 | 139 | { |
DavidEGrayson | 19:a11ffc903774 | 140 | int16_t reduction = (1 - magn/(1<<20)) * maxSpeed; |
DavidEGrayson | 19:a11ffc903774 | 141 | speedLeft = reduceSpeed(speedLeft, reduction); |
DavidEGrayson | 19:a11ffc903774 | 142 | speedRight = reduceSpeed(speedRight, reduction); |
DavidEGrayson | 19:a11ffc903774 | 143 | } |
DavidEGrayson | 19:a11ffc903774 | 144 | |
DavidEGrayson | 19:a11ffc903774 | 145 | if (det > 0) |
DavidEGrayson | 19:a11ffc903774 | 146 | { |
DavidEGrayson | 19:a11ffc903774 | 147 | speedLeft = reduceSpeed(speedLeft, det * 1000); |
DavidEGrayson | 18:b65fbb795396 | 148 | } |
DavidEGrayson | 18:b65fbb795396 | 149 | else |
DavidEGrayson | 18:b65fbb795396 | 150 | { |
DavidEGrayson | 19:a11ffc903774 | 151 | speedRight = reduceSpeed(speedRight, -det * 1000); |
DavidEGrayson | 18:b65fbb795396 | 152 | } |
DavidEGrayson | 19:a11ffc903774 | 153 | motorsSpeedSet(speedLeft, speedRight); |
DavidEGrayson | 18:b65fbb795396 | 154 | } |
DavidEGrayson | 18:b65fbb795396 | 155 | |
DavidEGrayson | 20:dbec34f0e76b | 156 | motorsSpeedSet(0, 0); |
DavidEGrayson | 20:dbec34f0e76b | 157 | } |
DavidEGrayson | 20:dbec34f0e76b | 158 | |
DavidEGrayson | 20:dbec34f0e76b | 159 | void finalSettleIn() |
DavidEGrayson | 20:dbec34f0e76b | 160 | { |
DavidEGrayson | 20:dbec34f0e76b | 161 | led1 = 1; led2 = 1; led3 = 1; led4 = 0; |
DavidEGrayson | 19:a11ffc903774 | 162 | |
DavidEGrayson | 20:dbec34f0e76b | 163 | const int16_t settleSpeed = 200; |
DavidEGrayson | 20:dbec34f0e76b | 164 | const int16_t settleModificationStrength = 100; |
DavidEGrayson | 20:dbec34f0e76b | 165 | |
DavidEGrayson | 20:dbec34f0e76b | 166 | Timer timer; |
DavidEGrayson | 20:dbec34f0e76b | 167 | timer.start(); |
DavidEGrayson | 20:dbec34f0e76b | 168 | |
DavidEGrayson | 20:dbec34f0e76b | 169 | // State 0: rotating |
DavidEGrayson | 20:dbec34f0e76b | 170 | // State 1: Trying to get into final orientation: want [cos, sin] == [1<<30, 0]. |
DavidEGrayson | 20:dbec34f0e76b | 171 | uint8_t state = 0; |
DavidEGrayson | 20:dbec34f0e76b | 172 | |
DavidEGrayson | 19:a11ffc903774 | 173 | while(1) |
DavidEGrayson | 19:a11ffc903774 | 174 | { |
DavidEGrayson | 20:dbec34f0e76b | 175 | updateReckonerFromEncoders(); |
DavidEGrayson | 20:dbec34f0e76b | 176 | |
DavidEGrayson | 20:dbec34f0e76b | 177 | float dot = dotProduct(); |
DavidEGrayson | 20:dbec34f0e76b | 178 | int16_t speedModification = -dot * settleModificationStrength; |
DavidEGrayson | 20:dbec34f0e76b | 179 | if (speedModification > settleModificationStrength) |
DavidEGrayson | 20:dbec34f0e76b | 180 | { |
DavidEGrayson | 20:dbec34f0e76b | 181 | speedModification = settleModificationStrength; |
DavidEGrayson | 20:dbec34f0e76b | 182 | } |
DavidEGrayson | 20:dbec34f0e76b | 183 | else if (speedModification < -settleModificationStrength) |
DavidEGrayson | 20:dbec34f0e76b | 184 | { |
DavidEGrayson | 20:dbec34f0e76b | 185 | speedModification = -settleModificationStrength; |
DavidEGrayson | 20:dbec34f0e76b | 186 | } |
DavidEGrayson | 20:dbec34f0e76b | 187 | |
DavidEGrayson | 20:dbec34f0e76b | 188 | if (state == 0 && timer.read_ms() >= 6000 && reckoner.cos > (1 << 29)) |
DavidEGrayson | 19:a11ffc903774 | 189 | { |
DavidEGrayson | 20:dbec34f0e76b | 190 | led1 = 1; led2 = 0; led3 = 1; led4 = 0; |
DavidEGrayson | 20:dbec34f0e76b | 191 | state = 1; |
DavidEGrayson | 20:dbec34f0e76b | 192 | } |
DavidEGrayson | 20:dbec34f0e76b | 193 | |
DavidEGrayson | 20:dbec34f0e76b | 194 | int16_t rotationSpeed; |
DavidEGrayson | 20:dbec34f0e76b | 195 | if (state == 1) |
DavidEGrayson | 20:dbec34f0e76b | 196 | { |
DavidEGrayson | 20:dbec34f0e76b | 197 | float s = (float)reckoner.sin / (1 << 30); |
DavidEGrayson | 20:dbec34f0e76b | 198 | rotationSpeed = -s * 300; |
DavidEGrayson | 20:dbec34f0e76b | 199 | } |
DavidEGrayson | 20:dbec34f0e76b | 200 | else |
DavidEGrayson | 20:dbec34f0e76b | 201 | { |
DavidEGrayson | 20:dbec34f0e76b | 202 | rotationSpeed = settleSpeed; |
DavidEGrayson | 20:dbec34f0e76b | 203 | } |
DavidEGrayson | 20:dbec34f0e76b | 204 | |
DavidEGrayson | 20:dbec34f0e76b | 205 | int16_t speedLeft = -rotationSpeed + speedModification; |
DavidEGrayson | 20:dbec34f0e76b | 206 | int16_t speedRight = rotationSpeed + speedModification; |
DavidEGrayson | 20:dbec34f0e76b | 207 | motorsSpeedSet(speedLeft, speedRight); |
DavidEGrayson | 19:a11ffc903774 | 208 | } |
DavidEGrayson | 20:dbec34f0e76b | 209 | |
DavidEGrayson | 20:dbec34f0e76b | 210 | led1 = 1; led2 = 1; led3 = 1; led4 = 1; |
DavidEGrayson | 20:dbec34f0e76b | 211 | motorsSpeedSet(0, 0); |
DavidEGrayson | 18:b65fbb795396 | 212 | } |