Excavation inspection and clearance system

1 . An excavation inspection and clearance method comprising:

navigating an excavation with a plurality of autonomous agents;

generating a graph corresponding to the excavation, wherein edges correspond to pathways of the excavation along which the plurality of autonomous agents may travel and nodes correspond to junctions joining the pathways;

determining a search strategy using the graph;

searching, according to the search strategy and using one or more sensors of each of the plurality of autonomous agents, to identify at least one of persons and equipment in proximity of the plurality of autonomous agents while navigating the excavation; and

determining clear zones around each of the plurality of autonomous agents according to at least one of a lack of persons and a lack of equipment in proximity of the plurality of autonomous agents while navigating the excavation;

wherein a first autonomous agent of the plurality of autonomous agents monitors at least one of an edge and a node of one portion of the graph while a second autonomous agent of the plurality of autonomous agents creates and maintains a clear zone in another part of the graph;

wherein the graph includes a plurality of sub-graphs, cleared individually and monitored by an autonomous agent of the plurality of autonomous agents until two or more of the sub-graphs can be joined to become larger sub-graphs, and the entire graph is cleared, and

wherein the plurality of autonomous agents are configured to navigate the excavation such that the clear zones are maintained and can be joined to form a larger clear zone in the excavation.

2 . The excavation inspection and clearance method of claim 1 , further comprising receiving a map of the excavation.

3 . The excavation inspection and clearance method of claim 1 , further comprising determining a path through the graph for each of the plurality of autonomous agents such that the path creates and maintains a clear zone in the graph.

4 . The excavation inspection and clearance method of claim 1 , wherein the plurality of autonomous agents are configured to share their location with each other.

5 . The excavation inspection and clearance method of claim 1 , wherein the plurality of autonomous agents are configured to determine clear zones of the excavation recursively.

6 . The excavation inspection and clearance method of claim 1 , wherein a central server may control the plurality of autonomous agents.

7 . The excavation inspection and clearance method of claim 1 , wherein a master autonomous agent of the plurality of autonomous agents controls one or more other slave autonomous agents of the plurality of autonomous agents.

8 . The excavation inspection and clearance method of claim 1 , further comprising signaling the clear zone.

9 . The excavation inspection and clearance method of claim 1 , wherein the plurality of autonomous agents are configured to navigate, at least in part, according to data from the one or more sensors.

10 . The excavation inspection and clearance method of claim 1 , wherein each of the plurality of autonomous agents is configured to stay with a person upon identification of a person.

11 . The excavation inspection and clearance method of claim 1 , wherein the plurality of autonomous agents are configured to identify equipment.

12 . The excavation inspection and clearance method of claim 1 , wherein the one or more sensors comprise one or more distance/range sensors.

13 . The excavation inspection and clearance method of claim 1 , wherein the one or more sensors comprise one or more image sensors.

14 . The excavation inspection and clearance method of claim 1 , wherein the one or more sensors are be configured to generate three-dimensional data relating to the excavation.

15 . The excavation inspection and clearance method of claim 1 , wherein the plurality of autonomous agents comprise an inertial measurement unit (IMU) configured to sense position and orientation changes of the plurality of autonomous agents based on inertial acceleration.

16 . An excavation inspection and clearance system comprising:

a plurality of autonomous agents configured to:

navigate an excavation;

generate a graph corresponding to the excavation, wherein edges correspond to pathways of the excavation along which the plurality of autonomous agents may travel and nodes correspond to junctions joining the pathways;

determine a search strategy using the graph;

search, according to the search strategy and using one or more sensors of the plurality of autonomous agents, to identify at least one of persons and equipment in proximity of the plurality of autonomous agents, while navigating the excavation; and

determine clear zones around each of the plurality of autonomous agents according to at least one of a lack of persons and equipment in proximity of the plurality of autonomous agents while navigating the excavation;

wherein a first autonomous agent of the plurality of autonomous agents monitors at least one of an edge and a node of one portion of the graph while a second autonomous agent of the plurality of autonomous agents creates and maintains a clear zone in another part of the graph;

wherein the graph includes a plurality of sub-graphs, cleared individually and monitored by an autonomous agent of the plurality of autonomous agents until two or more of the sub-graphs can be joined to become larger sub-graphs, and the entire graph is cleared; and

wherein the plurality of autonomous agents are configured to navigate the excavation such that the clear zones are maintained and can be joined to form a larger clear zone in the excavation.