def self.position_convert(pos)
    lat = pos.latitude
    lng = pos.longitude

    lat = (lat * 0xffffff) + 90
    puts lat

    bytes = []
    bytes << lat % 256
    bytes << (lat % 256**2) - bytes[0]
    bytes << lat - bytes[0] - bytes[1]
    y bytes
    bytes.pack('a3a3')
  end