johnny-five/eg/boe-test-servos.js

Firmata based Arduino Programming Framework.

var five = require("../lib/johnny-five.js"),
    board, Navigator, bot, left, right, sonar, scanner, servos,
    expandWhich, reverseDirMap, scale;

reverseDirMap = {
  right: "left",
  left: "right"
};

scale = function( speed, low, high ) {
  return Math.floor( five.Fn.map( speed, 0, 5, low, high ) );
};


/**
 * Navigator
 * @param {Object} opts Optional properties object
 */
function Navigator( opts ) {

  // Boe Navigator continuous are calibrated to stop at 90°
  this.center = opts.center || 90;

  this.servos = {
    right: new five.Servo({ pin: opts.right, type: "continuous" }),
    left: new five.Servo({ pin: opts.left, type: "continuous" })
  };

  this.direction = opts.direction || {
    right: this.center,
    left: this.center
  };

  this.speed = opts.speed == null ? 0 : opts.speed;

  this.history = [];
  this.which = "forward";
  this.isTurning = false;

  setTimeout(function() {
    this.fwd(1).fwd(0);
  }.bind(this), 10);
}

/**
 * move
 * @param  {Number} right Speed/Direction of right servo
 * @param  {Number} left  Speed/Direction of left servo
 * @return {Object} this
 */
Navigator.prototype.move = function( right, left ) {

  // Quietly ignore duplicate instructions
  if ( this.direction.right === right &&
        this.direction.left === left ) {
    return this;
  }

  // Servos are mounted opposite of each other,
  // the values for left and right will be in
  // opposing directions.
  this.servos.right.move( right );
  this.servos.left.move( left );

  // Store a recallable history of movement
  this.history.push({
    timestamp: Date.now(),
    right: right,
    left: left
  });

  // Update the stored direction state
  this.direction.right = right;
  this.direction.left = left;

  return this;
};


// TODO: DRY OUT!!!!!!!


/**
 * forward Move the bot forward
 * fwd Move the bot forward
 *
 * @param  {Number}0-5, 0 is stopped, 5 is fastest
 * @return {Object} this
 */
Navigator.prototype.forward = Navigator.prototype.fwd = function( speed ) {
  speed = speed == null ? 1 : speed;

  var scaled = scale( speed, this.center, 110 );

  this.speed = speed;
  this.which = "forward";

  return this.move( this.center - (scaled - this.center), scaled );
};

/**
 * reverse Move the bot in reverse
 * rev Move the bot in reverse
 *
 * @param  {Number}0-5, 0 is stopped, 5 is fastest
 * @return {Object} this
 */
Navigator.prototype.reverse = Navigator.prototype.rev = function( speed ) {
  speed = speed == null ? 1 : speed;

  var scaled = scale( speed, this.center, 110 );

  this.speed = speed;
  this.which = "reverse";

  console.log( scaled, this.center - (scaled - this.center) );

  return this.move( scaled, this.center - (scaled - this.center) );
};

/**
 * stop Stops the bot, regardless of current direction
 * @return {Object} this
 */
Navigator.prototype.stop = function() {
  this.speed = this.center;
  this.which = "stop";

  return this.move( this.center, this.center );
};

/**
 * right Turn the bot right
 * @return {Object} this
 */

/**
 * left Turn the bot lefts
 * @return {Object} this
 */


[ "right", "left" ].forEach(function( dir ) {
  Navigator.prototype[ dir ] = function() {
    var actual = this.direction[ reverseDirMap[ dir ] ];

    if ( !this.isTurning ) {
      this.isTurning = true;
      this.move( actual, actual );

      // Restore direction after turn
      setTimeout(function() {

        this[ this.which ]( this.speed );
        this.isTurning = false;

      }.bind(this), 750);
    }

    return this;
  };
});

expandWhich = function( which ) {
  var parts, translations;

  translations = [
    {
      f: "forward",
      r: "reverse",
      fwd: "forward",
      rev: "reverse"
    },
    {
      r: "right",
      l: "left"
    }
  ];

  if ( which.length === 2 ) {
    parts = [ which[0], which[1] ];
  }

  if ( !parts.length && /\-/.test(which) ) {
    parts = which.split("-");
  }

  return parts.map(function( val, i ) {
    return translations[ i ][ val ];
  }).join("-");
};

Navigator.prototype.pivot = function( which, time ) {
  var actual, directions, scaled;

  scaled = scale( this.speed, this.center, 110 );
  which = expandWhich( which );

  directions = {
    "forward-right": function() {
      this.move( this.center, scaled );
    },
    "forward-left": function() {
      this.move( this.center - (scaled - this.center), this.center );
    },
    "reverse-right": function() {
      this.move( scaled, this.center );
    },
    "reverse-left": function() {
      this.move( this.center, this.center - (scaled - this.center) );
    }
  };

  directions[ which ].call( this, this.speed );

  setTimeout(function() {

    this[ this.which ]( this.speed );

  }.bind(this), time || 1000 );

  return this;
};


board = new five.Board();
board.on("ready", function() {

  sonar = new five.Sonar({
    pin: "A2",
    freq: 100
  });
  sonar.on("change", function() {
    console.log( "Object is " + this.inches + "inches away" );
  });

  scanner = new five.Servo(12);
  scanner.sweep();

  this.repl.inject({
    // create a bot, right servo = pin 10, left servo = pin 11
    b: new Navigator({ right: 10, left: 11 })
  });
});