Apparatus and method for creating probability-based radio map for cooperative intelligent robots
An apparatus for creating a radio map includes a radio signal acquiring unit that acquires information on radio signals between one or more cooperative intelligent robots, a radio environment modeling unit that estimates radio strength for each cell configuring the radio map from the information on radio signals acquired by the radio signal acquiring unit, and a radio map creating unit that classifies a communication region of each cell and models the radio map according to the radio strength for each cell estimated by the radio environment modeling unit.
1. An apparatus for creating a radio map in a communication system for cooperative intelligent robots including one or more routing robots for performing signal routing and a mission robot for performing a task, the apparatus being included in a leader robot of the one or more routing robots and comprising:
a radio signal acquiring unit that acquires information on radio signals between the cooperative intelligent robots;
a radio environment modeling unit that estimates radio strength for each cell of the radio map from the information on radio signals acquired by the radio signal acquiring unit; and
a radio map creating unit that classifies a communication region of each cell and models the radio map according to the radio strength for each cell estimated by the radio environment modeling unit,
wherein the one or more routing robots are cooperatively operated to securely establish an uninterrupted network between the cooperative intelligent robots by using the radio map to move to a communication region where communication between the cooperative intelligent robots is not disconnected, and
wherein the mission robot is configured to use the radio ma to search for a shortest path to a target in the communication region and move to the target.
2. The apparatus of claim 1 , wherein the radio signal acquiring unit carries a WPAN communication module and receives the information on radio signals from one or more neighboring robots.
3. The apparatus of claim 1 , wherein the information on radio signals includes radio strength, communication link quality, and a relative position.
4. The apparatus of claim 1 , wherein the radio map creating unit matches the radio map with a grid of an actual local map.
5. The apparatus of claim 1 , wherein the radio environment modeling unit calculates a radio environment variable (n) using an acquired movement distance of each robot and an acquired radio strength, and estimates a radio strength (L) in each grid cell while changing a distance value (d) to one or more grid cells of the radio map using the calculated radio environment variable (n).
6. The apparatus of claim 1 , wherein the radio environment modeling unit uses a maximum likelihood estimate (MLE) technique to estimate an average noise for noise modeling.
7. The apparatus of claim 1 , wherein the radio environment modeling unit uses a Cramer-Rao bound technique to estimate a noise distribution.
8. The apparatus of claim 1 , wherein the radio map creating unit receives a radio strength estimation value for each cell of the radio map from one or more other routing robots, and extracts a representative value from among radio strengths in consideration of a priority of the routing robots.
9. The apparatus of claim 1 , further comprising a radio map sharing unit that transmits the created radio map to the one or more routing robots and the mission robots.
10. A method of creating a radio map in a communication system for cooperative intelligent robots including one or more routing robots for performing signal routing and a mission robot for performing a task, the method being performed in a leader robot of the one or more routing robots and comprising:
acquiring information on radio signals between the cooperative intelligent robots;
estimating radio strength for each cell of the radio map from the acquired information on radio signals; and
classifying a communication region of each cell and modeling the radio map according to the estimated radio strength for each cell,
wherein the one or more routing robots are cooperatively operated to securely establish an uninterrupted network between the cooperative intelligent robots by using the radio map to move to a communication region where communication between the cooperative intelligent robots is not disconnected, and
wherein the mission robot is configured to use the radio map to search for a shortest path to a target in the communication region and move to the target.
11. The method of claim 10 , wherein the information on radio signals includes radio strength, communication link quality, and a relative position.
12. The method of claim 10 , further comprising matching the radio map with a grid of an actual local map.
13. The method of claim 10 , wherein the estimating of the radio strength includes:
calculating a radio environment variable (n) using an acquired movement distance of each robot and radio strength, and
estimating a radio strength value (L) in each grid cell while changing a distance value (d) to one or more grid cells of the radio map using the calculated, radio environment variable (n).
14. The method of claim 10 , wherein the creating of the radio map includes:
receiving a radio strength estimation value for each cell of the radio map from one or more other routing robots, and
extracting a representative value from among radio strengths in consideration of a priority of the routing robots.
15. The method of claim 10 , further comprising transmitting the created radio map to the one or more routing robots and the mission robot.