Three-dimensional localization of a device within a grain bin

A method of three-dimensional localization of a robot in an enclosed bulk store for granular material, the method comprising:

• wirelessly transmitting, from a master unit, a first localization signal;
• independently receiving, by each lateration unit of a plurality of lateration units distributed about outside an area of an enclosed bulk store within which the robot is to be localized, the first localization signal;
• responsive to and upon receipt of the first localization signal at each lateration unit of the plurality of lateration units, independently starting a timer at each lateration unit, such that a plurality of timers are independently started;
• responsive to and upon receipt of the first localization signal by the robot, wirelessly transmitting a second localization signal for receipt by the plurality of lateration units, wherein the second localization signal is sent responsive to and upon receipt of the first localization signal;
• and
• responsive to and upon independently receiving the second localization signal at each lateration unit of the plurality of lateration units:
• stopping the timer at each lateration unit at the independent time of receipt of the second lateration unit at each lateration unit;
• and
• independently wirelessly transmitting, from each lateration unit, a timer count signal to a localization unit, the timer count signal identifying the transmitting lateration unit and a count of its timer upon receipt of the second lateration signal;
• receiving, at a localization unit located remotely from the lateration units, the respective timer count signals from each of the plurality of lateration units;
• and
• utilizing, by the lateration unit, the plurality of timer counts from the received timer count signals along with respective distances between the master unit and each lateration unit of the plurality of lateration units to three-dimensionally localize the robot via time-of-flight lateration.