I Guess I'm an Electrical Engineer now.

So Matt Hart passed off the arm to me (Matt Tannenbaum) this week for a final wiring. There were two main hurdles to cross; the wiring of two relays to act as polarity reversing relays and finding a way to safely trigger those relays using the arduino (+5v vs. +12v)

First things first was to make the arm look like an arm, a sleeve was added, as well as a few mechanical tweaks to make it work better.

Next came the actual wiring. Two 40amp, 12v relays were wired in a polarity switching configuration.

One this was connected and soldiered, two NPN transistors were used as switches to allow the arduino to switch a 7.5v regulated supply.

From here, it's just final assembly.

 We made a quick stand to hold all of the components

 Basic placement to get a feeling for size

 We lacked the necessary parts to attach the lever arm to the motor the correct way to it was fudged a bit. it is working so far. 

 Had to create a quick mounting plate for the motor, the mill made quick work of it. 

 Limit switch one, we added this to help tell the arduino where the armature is at all times. 

Limit switch two, once again this is to help keep track of the armature

 All assembled

Wiring Schematic

How does one wire a dap-bot? Using Fritzing of course!

Quick sketch of our final idea for moving the armature.

Final fabrication will be competed over the weekend.
Final CAD will be posted soon for your viewing pleasure. 

Fabrication!

Here is our current revision of the linkage we are planning to use. it is make of 0.25" angle aluminium. 

The next step was to secure the foam fist to the part of the linkage that is made to extend out. We came up with the idea to use spray expanding insulation to secure the fist to the piece of aluminium. 

After a night of curing the foam insulation expanded nicely and is holding the fist to the piece of angle nicely. 

Unfortunately over night the rid we had set up to hold the metal straight broke and it set slightly angled. This should not be to much of an issue. 

After shaving a bit of the foam off we decided to integrate. Its looking promising. 

Thursday Lab Update

BRUINS!
Bruins logo finished in Solid Works and ready to print! It's 5 inches in diameter and will be positioned on the front of the fist, ring style.

Final design for the arm. The arm will rock in a back and forth motion with the foam fist positioned at the end. Parts will be made out of aluminum. The project is coming along smoothly!

Ultrasonic sensors came in the mail today, Brandon was pretty excited. integration of code and hardware can begin soon. 

The foam fist also came in the mail today! mounting brackets are being design so the fist can be attached to the movement linkage. 

FIST BUMP2

rev.1a

DapsBot beta code.

#include <Servo.h> 

const int buttonPin = 2;     // the number of the pushbutton pin

const int pingPin = 7;

int buttonState = 0;         // variable for reading the pushbutton status

Servo myservo;  // create servo object to control a servo 

void setup() {

  

  Serial.begin(9600); // initialize serial communication:

  myservo.attach(9);  // attaches the servo on pin 9 to the servo object 

  // initialize the pushbutton pin as an input:

  pinMode(buttonPin, INPUT);

}

void loop()

{

  // establish variables for duration of the ping, 

  // and the distance result in inches and centimeters:

  long duration, cm;

  // The PING))) is triggered by a HIGH pulse of 2 or more microseconds.

  // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:

  pinMode(pingPin, OUTPUT);

  digitalWrite(pingPin, LOW);

  delayMicroseconds(2);

  digitalWrite(pingPin, HIGH);

  delayMicroseconds(5);

  digitalWrite(pingPin, LOW);

  // The same pin is used to read the signal from the PING))): a HIGH

  // pulse whose duration is the time (in microseconds) from the sending

  // of the ping to the reception of its echo off of an object.

  pinMode(pingPin, INPUT);

  duration = pulseIn(pingPin, HIGH);

  buttonState = digitalRead(buttonPin);

  // convert the time into a distance

  cm = microsecondsToCentimeters(duration);

  

  Serial.print(cm);

  Serial.print("cm");

  

  delay(100);

  if( cm < 10){

      myservo.write(180);                  // sets the servo position according to the scaled value 

      while( buttonState == HIGH){

      }

      myservo.write(0);

  }

  

}

long microsecondsToCentimeters(long microseconds)

{

  // The speed of sound is 340 m/s or 29 microseconds per centimeter.

  // The ping travels out and back, so to find the distance of the

  // object we take half of the distance travelled.

  return microseconds / 29 / 2;

}

Link to The Github gist-

https://gist.github.com/teamteamname/7472152

DapsBot

Ever had the problem where you do something awesome, but there's no one around to give you proper daps? Well suffer no longer, with the DapsBot just throw that fist out and away a proper dap.

 Stay tuned for more.

Etch a Sketch Clock