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

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Text this: Navigation of free-ranging automated guided vehicles by solving the hyperbolic loci of the differential times-of-flight from ultrasonic beacons