Hello everyone, I encountered a problem in my project, my project about a smart robot car with Arduino Uno with ESP8266 board , when I wrote the stopping condition of the car in the loop method does not stop but continues to move automatically and does not stop, how do I stop the car permanently in this case? #define speedPinR 3 #define RightDirectPin1 12 #define RightDirectPin2 11 #define speedPinL 6 #define LeftDirectPin1 7 #define LeftDirectPin2 8 #define LPT 2 int sensor=A0; #define SERVO_PIN 9 #define Echo_PIN 2 #define Trig_PIN 10 #define BUZZ_PIN 13 #define FAST_SPEED 250 #define SPEED 120 #define TURN_SPEED 200 #define BACK_SPEED1 255 #define BACK_SPEED2 90 #define USE_ARDUINO_INTERRUPTS true int Threshold = 550; int leftscanval, centerscanval, rightscanval, ldiagonalscanval, rdiagonalscanval; const int distancelimit = 30; const int sidedistancelimit = 30; int distance; int numcycles = 0; const int turntime = 250; const int backtime = 300; int thereis; Servo head; /*motor control*/ void go_Advance(void) //Forward { digitalWrite(RightDirectPin1, HIGH); digitalWrite(RightDirectPin2, LOW); digitalWrite(LeftDirectPin1, HIGH); digitalWrite(LeftDirectPin2, LOW); } void go_Left() //Turn left { digitalWrite(RightDirectPin1, HIGH); digitalWrite(RightDirectPin2, LOW); digitalWrite(LeftDirectPin1, LOW); digitalWrite(LeftDirectPin2, HIGH); } void go_Right() //Turn right { digitalWrite(RightDirectPin1, LOW); digitalWrite(RightDirectPin2, HIGH); digitalWrite(LeftDirectPin1, HIGH); digitalWrite(LeftDirectPin2, LOW); } void go_Back() //Reverse { digitalWrite(RightDirectPin1, LOW); digitalWrite(RightDirectPin2, HIGH); digitalWrite(LeftDirectPin1, LOW); digitalWrite(LeftDirectPin2, HIGH); } void stop_Stop() //Stop { digitalWrite(RightDirectPin1, LOW); digitalWrite(RightDirectPin2, LOW); digitalWrite(LeftDirectPin1, LOW); digitalWrite(LeftDirectPin2, LOW); set_Motorspeed(0, 0); } /*set motor speed */ void set_Motorspeed(int speed_L, int speed_R) { analogWrite(speedPinL, speed_L); analogWrite(speedPinR, speed_R); } void buzz_ON() //open buzzer { for (int i = 0; i < 100; i++) { digitalWrite(BUZZ_PIN, LOW); delay(2);//wait for 1ms digitalWrite(BUZZ_PIN, HIGH); delay(2);//wait for 1ms } } void buzz_OFF() //close buzzer { digitalWrite(BUZZ_PIN, HIGH); } void alarm() { buzz_ON(); buzz_OFF(); } /*detection of ultrasonic distance*/ int watch() { long echo_distance; digitalWrite(Trig_PIN, LOW); delayMicroseconds(5); digitalWrite(Trig_PIN, HIGH); delayMicroseconds(15); digitalWrite(Trig_PIN, LOW); echo_distance = pulseIn(Echo_PIN, HIGH); echo_distance = echo_distance * 0.01657; //how far away is the object in cm //Serial.println((int)echo_distance); return round(echo_distance); } //Meassures distances to the right, left, front, left diagonal, right diagonal and asign them in cm to the variables rightscanval, //leftscanval, centerscanval, ldiagonalscanval and rdiagonalscanval (there are 5 points for distance testing) String watchsurrounding() { /* obstacle_status is a binary integer, its last 5 digits stands for if there is any obstacles in 5 directions, for example B101000 last 5 digits is 01000, which stands for Left front has obstacle, B100111 means front, right front and right ha */ int obstacle_status = B100000; centerscanval = watch(); if (centerscanval < distancelimit) { stop_Stop(); alarm(); obstacle_status = obstacle_status | B100; } head.write(120); delay(100); ldiagonalscanval = watch(); if (ldiagonalscanval < distancelimit) { stop_Stop(); alarm(); obstacle_status = obstacle_status | B1000; } head.write(170); //Didn't use 180 degrees because my servo is not able to take this angle delay(300); leftscanval = watch(); if (leftscanval < sidedistancelimit) { stop_Stop(); alarm(); obstacle_status = obstacle_status | B10000; } head.write(90); //use 90 degrees if you are moving your servo through the whole 180 degrees delay(100); centerscanval = watch(); if (centerscanval < distancelimit) { stop_Stop(); alarm(); obstacle_status = obstacle_status | B100; } head.write(40); delay(100); rdiagonalscanval = watch(); if (rdiagonalscanval < distancelimit) { stop_Stop(); alarm(); obstacle_status = obstacle_status | B10; } head.write(0); delay(100); rightscanval = watch(); if (rightscanval < sidedistancelimit) { stop_Stop(); alarm(); obstacle_status = obstacle_status | 1; } head.write(90); //Finish looking around (look forward again) delay(300); String obstacle_str = String(obstacle_status, BIN); obstacle_str = obstacle_str.substring(1, 6); return obstacle_str; //return 5-character string standing for 5 direction obstacle status } void auto_avoidance() { ++numcycles; if (numcycles >= LPT) { //Watch if something is around every LPT loops while moving forward stop_Stop(); String obstacle_sign = watchsurrounding(); // 5 digits of obstacle_sign binary value means the 5 direction obstacle status Serial.print("begin str="); Serial.println(obstacle_sign); if ( obstacle_sign == "10000") { Serial.println("SLIT right"); set_Motorspeed(FAST_SPEED, SPEED); go_Advance(); delay(turntime); stop_Stop(); } else if ( obstacle_sign == "00001" ) { Serial.println("SLIT LEFT"); set_Motorspeed(SPEED, FAST_SPEED); go_Advance(); delay(turntime); stop_Stop(); } else if ( obstacle_sign == "11100" || obstacle_sign == "01000" || obstacle_sign == "11000" || obstacle_sign == "10100" || obstacle_sign == "01100" || obstacle_sign == "00100" || obstacle_sign == "01000" ) { Serial.println("hand right"); go_Right(); set_Motorspeed(TURN_SPEED, TURN_SPEED); delay(turntime); stop_Stop(); } else if ( obstacle_sign == "00010" || obstacle_sign == "00111" || obstacle_sign == "00011" || obstacle_sign == "00101" || obstacle_sign == "00110" || obstacle_sign == "01010" ) { Serial.println("hand left"); go_Left();//Turn left set_Motorspeed(TURN_SPEED, TURN_SPEED); delay(turntime); stop_Stop(); } else if ( obstacle_sign == "01111" || obstacle_sign == "10111" || obstacle_sign == "11111" ) { Serial.println("hand back right"); go_Left(); set_Motorspeed( FAST_SPEED, SPEED); delay(backtime); stop_Stop(); } else if ( obstacle_sign == "11011" || obstacle_sign == "11101" || obstacle_sign == "11110" || obstacle_sign == "01110" ) { Serial.println("hand back left"); go_Right(); set_Motorspeed( SPEED, FAST_SPEED); delay(backtime); stop_Stop(); } else Serial.println("no handle"); numcycles = 0; //Restart count of cycles } else { set_Motorspeed(SPEED, SPEED); go_Advance(); // if nothing is wrong go forward using go() function above. delay(backtime); stop_Stop(); } //else Serial.println(numcycles); distance = watch(); // use the watch() function to see if anything is ahead (when the robot is just moving forward and not looking around it will test the distance in front) if (distance distancelimit) { thereis = 0; } //Count is restarted if (thereis > 25) { Serial.println("final stop"); stop_Stop(); // Since something is ahead, stop moving. thereis = 0; } } void stopCar(){ set_Motorspeed(0, 0); } void setup() { /*setup L298N pin mode*/ pinMode(RightDirectPin1, OUTPUT); pinMode(RightDirectPin2, OUTPUT); pinMode(speedPinL, OUTPUT); pinMode(LeftDirectPin1, OUTPUT); pinMode(LeftDirectPin2, OUTPUT); pinMode(speedPinR, OUTPUT); stop_Stop();//stop move /*init HC-SR04*/ pinMode(Trig_PIN, OUTPUT); pinMode(Echo_PIN, INPUT); /*init buzzer*/ pinMode(BUZZ_PIN, OUTPUT); digitalWrite(BUZZ_PIN, HIGH); buzz_OFF(); digitalWrite(Trig_PIN, LOW); /*init servo*/ head.attach(SERVO_PIN); head.write(90); delay(2000); Serial.begin(9600); } void loop() { auto_avoidance(); int msensor =analogRead(sensor); if(msensor>90 || msensor<200){ Serial.println("car want self-stop automatically "); go_Right(); stopCar(); } delay(20); }```

Hmmm. You haven't exactly given us all the data... Could you post code...?

void loop() { auto_avoidance(); int msensor =analogRead(sensor); if(msensor>90 || msensor<200){ Serial.println("car want self-stop automatically "); go_Right(); stopCar(); } delay(20); }

Hello, do yourself a favour and please read How to get the best out of this forum and modify your 2 post accordingly - esp. posting ALL the code, with code tags... You might not get any further answer otherwise.

[image] rana007: if(msensor>90 || msensor<200){ Serial.println("car want self-stop automatically "); go_Right(); stopCar(); } So you want any value between 91 and 199 to do the go right and stop thing...?

yes ,and otherwise the car will compelete driving.

otherwise, the car will complete driving

post ALL the code.. not just bits of it. You sure this is supposed to be an OR (||)... or an AND (&&)... ? [image] rana007: msensor>90 || msensor<200 This will ALWAYS be true!

I put all code ,but in if condition I write || because I just need one value.

Loop problem in method calling

Projects Programming

J-M-L November 12, 2021, 5:22pm 2

a big kick in the car may be ?

for more ideas, do yourself a favour and please read How to get the best out of this forum and modify your post accordingly (including code tags and necessary documentation of your ask).

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Loop problem in method calling

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