發送短信 : Fast loop closure detection via binary content

  _  _     _____     ____     _    _    ______   
 | \| ||  |  ___||  |  _ \\  | || | || |      \\ 
 |  ' ||  | ||__    | |_| || | || | || |  --  // 
 | .  ||  | ||__    | .  //  | \\_/ || |  --  \\ 
 |_|\_||  |_____||  |_|\_\\   \____//  |______// 
 `-` -`   `-----`   `-` --`    `---`   `------`