Guys in this lesson we show how you can use linear regression to more accurately calibrate turns for our robot car. We will take you through the math step-by-step, and then show how to code up the results. If you want to play along at home, you can get your Elegoo Robot Car HERE.
For your convenience, the code we developed in the lesson is included below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 | int ENA=5; int ENB=6; int IN1=7; int IN2=8; int IN3=9; int IN4=11; float d; int degRot; int left; int right; float v; void setup() { // put your setup code here, to run once: Serial.begin(9600); pinMode(ENA,OUTPUT); pinMode(ENB,OUTPUT); pinMode(IN1,OUTPUT); pinMode(IN2,OUTPUT); pinMode(IN3,OUTPUT); pinMode(IN4,OUTPUT); digitalWrite(ENA,HIGH); digitalWrite(ENB,HIGH); } void loop() { int wv; v=1.2; wv=(v-.35)/.0075; left=wv; right=wv; setSpeed(left,right); forward(5, v); turnRight(180, wv); forward(5, v); //calR(wv); //forward(8,v); //v=1.5; //wv=(v-.35)/.0075; //left=wv; //right=wv; //setSpeed(left,right); //backward(8,v); while(1==1){ } } void setSpeed(int leftVal,int rightVal){ analogWrite(ENA,leftVal); analogWrite(ENB,rightVal); } void forward(float d, float v){ float t; digitalWrite(IN1,HIGH); digitalWrite(IN2,LOW); digitalWrite(IN3,LOW); digitalWrite(IN4,HIGH); t=d/v*1000; delay(t); stopCar(); } void backward(float d, float v){ float t; digitalWrite(IN1,LOW); digitalWrite(IN2,HIGH); digitalWrite(IN3,HIGH); digitalWrite(IN4,LOW); t=d/v*1000; delay(t); stopCar(); } void turnRight(int deg, int wv){ float t; stopCar(); delay(100); analogWrite(ENA,125); analogWrite(ENB,125); digitalWrite(IN1,HIGH); digitalWrite(IN2,LOW); digitalWrite(IN3,HIGH); digitalWrite(IN4,LOW); t=(deg+6)/136.29*1000.; Serial.println(deg); delay(t); stopCar(); analogWrite(ENA,wv); analogWrite(ENB,wv); } void turnLeft(int deg, int wv){ float t; analogWrite(ENA,125); analogWrite(ENB,125); digitalWrite(IN1,LOW); digitalWrite(IN2,HIGH); digitalWrite(IN3,LOW); digitalWrite(IN4,HIGH); t=(deg+6)/136.29*1000.; Serial.println(deg); Serial.println(deg); delay(t); stopCar(); analogWrite(ENA,wv); analogWrite(ENB,wv); } void stopCar(){ digitalWrite(IN1,LOW); digitalWrite(IN2,LOW); digitalWrite(IN3,LOW); digitalWrite(IN4,LOW); } void calF(){ digitalWrite(IN1,HIGH); digitalWrite(IN2,LOW); digitalWrite(IN3,LOW); digitalWrite(IN4,HIGH); delay(5000); stopCar(); } void calB(){ digitalWrite(IN1,LOW); digitalWrite(IN2,HIGH); digitalWrite(IN3,HIGH); digitalWrite(IN4,LOW); delay(5000); stopCar(); } void calR(int wv){ stopCar(); analogWrite(ENA,125); analogWrite(ENB,125); digitalWrite(IN1,HIGH); digitalWrite(IN2,LOW); digitalWrite(IN3,HIGH); digitalWrite(IN4,LOW); delay(3000); analogWrite(ENA,wv); analogWrite(ENB,wv); stopCar(); } void calL(int wv){ analogWrite(ENA,125); analogWrite(ENB,125); digitalWrite(IN1,LOW); digitalWrite(IN2,HIGH); digitalWrite(IN3,LOW); digitalWrite(IN4,HIGH); delay(5000); analogWrite(ENA,wv); analogWrite(ENB,wv); stopCar(); } |