Wex, the One Eyed Watcher

Picture of Wex, the One Eyed Watcher

Wex detects your location with ultrasonic sensors then follows you with his one flashing eye.  His red "heartbeat" can be seen through his mouth.
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Step 1:

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Parts needed include:

Two ping ultrasonic sensors
Futaba s3103 servo
Radio Shack 276-0016 7 color led
Radio Shack  276-036 flashing red led
9 volt battery
480 ohm resistor
680 ohm resistor
Metal duct tape
Super glue
Case (print 3d parts--use a printing service to print them--make your own case)

The software "looks to the left--turn left if something there"
       "look to the right--turn right if something there"
       "look straight if nothing to the left or right"

#include <Servo.h>

Servo myservo;
const int pingPin = 7;
const int pingPin2 = 9;
long duration;
long duration1;

void setup ()
void loop ()
  pinMode (pingPin, OUTPUT);
  digitalWrite (pingPin, LOW);
  delayMicroseconds (2);
  digitalWrite (pingPin, HIGH);
  delayMicroseconds (5);
  digitalWrite (pingPin, LOW);
  pinMode (pingPin, INPUT);
  duration = pulseIn (pingPin, HIGH);
  if (duration <5000)
 // else
    pinMode (pingPin2, OUTPUT);
  digitalWrite (pingPin2, LOW);
  delayMicroseconds (2);
  digitalWrite (pingPin2, HIGH);
  delayMicroseconds (5);
  digitalWrite (pingPin2, LOW);
  pinMode (pingPin2, INPUT);
  duration1 = pulseIn (pingPin2, HIGH);
  if (duration1 <5000)
  if (duration >5000 and duration1 >5000)


Step 2:

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Print the case--expect shrinkage cracks.

Step 3:

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Cut up plastic scraps into a can.

Step 4:

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Add acetone (fingernail polish removal section of stores) and stir. Fill the cracks and let dry.

Step 5:

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Fasten Ping sensors to the triangular ear pieces.  Add wire wrap wire to the Ping pins. Super glue the ears to the case.

Step 6:

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Drill 1/8 inch holes in the "one eye eye" case for the Ping wires.

Step 7:

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Route the wires through the side of the case.

Step 8:

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Press the eye stalk on the servo and make sure the assembly fits in the case (if you use a different servo motor--the mounting slot in the case will have to be set up differently).

Step 9:

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Add a red wire wrap wire to the center lead of the 7 color led.
cool project, very life-like! I especially like the 3d printed feet. what did you print this on? do you have any tips to avoid shrinkage cracking on such a large enclosure?
MikeTheMaker (author)  amandaghassaei1 year ago
I printed with a MakerBot Replicator. Set a platform temperature of 110 degrees and close off the sides and front of the machine to prevent drafts (and reduce cracks). I only had the sides closed (paper taped over sides) and the open front may have contributed to the cracks. At 6 hours per print, I wasn't ready to retry on this particular piece :)

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