There's not really much to put here, mainly because it's so simple. Literally ryan's build, with a SRF04 hot glued on the front, wired up to the nano. It's just the code that's going to be a bitch. I haven't tried turning it, only going forwards and backwards, so that'll be fun. 

I'm pretty proud of this one- I was ONE jumper wire short. i needed a female to male one, but i couldn't find it, so i soldered a wire to the end of a single female header, and covered it with heat shrink. 

One more thing, i have a newfound hate for those cheap little servos. I think i've had to replace two, just because the gears wear down or something. Maybe i should cnc some metal ones...

I suck at coding, so thanks to this project: #Bracelet Dodges Obstacles, i'll be using that to base my code off of:

#define echo 8
#define trig 7
long duration,distance;

void setup() {
  
  Serial.begin(9600);
  pinMode(echo,INPUT);
  pinMode(trig,OUTPUT);
  pinMode(5,OUTPUT);
}

void loop() {
  
digitalWrite(trig,LOW);
delayMicroseconds(2);
digitalWrite(trig,HIGH);
delayMicroseconds(10);
digitalWrite(trig,LOW);

duration=pulseIn(echo,HIGH);
distance=(duration/(2*29));

if(distance>=500 || distance<=0){
  Serial.println("____");
  }
else{
  Serial.print(distance);
  Serial.println("cm.");
  digitalWrite(5,LOW);
}
if(distance<=45 && distance>=1){// distance in which the bracelet vibrates, you can edit according to your need

  digitalWrite(5,HIGH);
  Serial.println("Alarm!!!");
}
delay(400);
}