smart stick for blind people
#define trigPin 9 #define echoPin 8 #define Buzzer1 5 //active int sound = 250 ; void setup () { Serial . begin ( 9600 ); pinMode (trigPin, OUTPUT); pinMode (echoPin, INPUT); pinMode (Buzzer1, OUTPUT); } void loop () { Serial . begin ( 9600 ); long duration, distance; digitalWrite (trigPin, LOW); delay ( 2 ); digitalWrite (trigPin, HIGH); delay ( 10 ); digitalWrite (trigPin, LOW); duration = pulseIn (echoPin, HIGH); distance = (duration/ 2 ) / 29.1 ; digitalWrite (Buzzer1, LOW); if (distance< 20 ) { digitalWrite (Buzzer1, HIGH); delay ( 2000 ); } if (di...