Robot apparatus for detecting direction of sound source to move to sound source and method for operating the same

• US 6,308,114 B1
• Filed: 12/19/2000
• Issued: 10/23/2001
• Est. Priority Date: 04/20/1999
• Status: Expired due to Fees

• Current Assignee: In-Kwang Kim
• Original Assignee: In-Kwang Kim
• Inventors: Kim, In-Kwang
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): Marc, McDieunel, Marc, McDieunel
• Application Number:
  US09/719,866
• Time in Patent Office: 308 Days
• Field of Search: 700/245, 700/159, 700/174, 700/2, 700/9, 700/195, 340/679, 340/680, 340/683, 340/686.5, 702/185, 702/182, 702/150, 736/23, 704/260, 446/175, 318/507, 701/23
• US Class Current: 700/245
• CPC Class Codes: G01S 5/22 Position of source determined by co-ordinating a plurality of position lines defined by path-difference measurements G01S5/28 takes precedence

Abstract

A robot apparatus for detecting a sound signal outputted from a sound signal generating unit to move to a position of the sound signal generating device, wherein the sound signal has a specific pattern, includes: at least three sound receiving unit (114) for receiving the sound signal; a phase difference detecting unit (118) for detecting a phase difference between each sound signal from the sound receiving unit (114); a processing unit (125) for determining a position of the sound generating unit using the phase difference, to generate a moving control signal; and a moving unit (130) for moving the robot apparatus in response to the moving control signal.

Claims

1. A robot apparatus for detecting a sound signal outputted from a sound signal generating means to move to a position of the sound signal generating means, wherein the sound signal has a specific pattern, the robot apparatus comprising:

at least three sound receiving means for receiving the sound signal outputted from the sound signal generating means;

a phase difference detection means for detecting a phase difference between each sound signals from the sound receiving means;

a processing means for determining a position of the sound generating means using the phase difference, to generate a moving control signal; and

a moving means, in response to the moving control signal, for moving the robot apparatus to the position of the sound generating means.

2. The robot apparatus as recited in claim 1, wherein the sound receiving means includes a first, a second and a third receivers, each being disposed in an equilateral triangle form and being arranged to make maximum phase difference of sound signals received through the receivers to be within a half the frequency of the sound signal.

3. The robot apparatus as recited in claim 2, wherein the phase difference detection means includes:

a first amplifying and filtering unit for amplifying and filtering a first signal outputted from the first receiver;

a second amplifying and filtering unit for amplifying and filtering a second signal outputted from the second receiver;

a third amplifying and filtering unit for amplifying and filtering a third signal outputted from the third receiver;

a sound-pattern detection unit for receiving an output signal of the first amplifying and filtering unit and a clock having a predetermined period and outputting a detection signal in case where a period of the output signal is constant for a predetermined time; and

a phase detection unit, in response to the detection signal, for receiving output signals of the first, the second and the third amplifying and filtering units to detect phase differences between each output signal, and for outputting detected phase difference and interrupt signal which allows the phase difference data to be outputted to an exterior.

4. The robot apparatus as recited in claim 3, wherein the sound-pattern detection means includes:

an edge detector for detecting rising and falling edges of the first signal, to output pulse signals;

a pulse interval counter for receiving the clock and counting intervals between the pulse signals to output count value;

a setup period determinator for receiving the pulse signals from the edge detector and the count value from the pulse interval counter and determining whether a period of the first signal is constant or not;

a detection signal generator for receiving the pulse signals and a detection value from the setup period determinator and detecting whether the first signal is continuously inputted at a predetermined period, to output a detection signal; and

a clear signal generator for receiving the clock and an output signal of the edge detector to clear the detection signal outputted from the detection signal generator.

5. The robot apparatus as recited in claim 4, wherein the edge detector includes:

a first inverter for inverting the first signal;

a D flip flop for outputting a signal having a period corresponding to half the period of an output signal of the first inverter;

a plurality of second inverters, serially coupled to each other, for delaying an output signal of the D flip flop; and

an exclusive OR (XOR) gate for XORing the output signal of the D flip flop and an output signal of the second inverter.

6. The robot apparatus as recited in claim 5, wherein the pulse interval counter includes:

a plurality of third inverters, serially coupled to each other, for delaying the output signal of the edge detector;

a counter for counting an output signal of the third inverters to output count values to a first and a second output terminals in response to a signal inputted to a clock terminal;

a first AND gate for ANDing signals outputted from the first and the second output terminals of the counter;

a fourth inverter for inverting an output signal of the first AND gate;

a second AND gate for ANDing an output signal of the fourth inverter and the clock, to output an output signal to an clock terminal of the counter; and

a third AND gate for ANDing the output signal of the second output terminal of the counter and the output signal of the fourth inverter.

7. The robot apparatus as recited in claim 6, wherein the setup period determinator includes a first D flip flop having a clock terminal receiving the output signal of the edge detector, an input terminal receiving the output signal of the pulse interval counter, and inverting output terminal and non-inverting output terminal for respectively outputting output signals to the detection signal generator.

8. The robot apparatus as recited in claim 7, wherein the clear signal generator includes:

a second counter for counting the clock inputted through a clock terminal and outputting output signals through a first and a second output terminals;

a fourth AND gate for ANDing the output signals outputted from the first and the second output terminals of the second counter, to output an output signal to the clear terminal of the second D flip flop contained in the setup period determinator; and

an OR gate for ORing the output signal of the fourth AND gate and the output signal of the edge detector, to output an output signal to the clear signal of the second counter.

9. The robot apparatus as recited in claim 8, wherein the detection signal generator includes:

a third counter for counting a signal inputted through a clock terminal and outputting output signals through a first and a second output terminals, whose clear terminal is coupled to the non-inverting output terminal of the second D flip flop of the setup period determinator;

a fifth AND gate for ANDing the output signals of the first and the second output terminals of the third counter, to output the detection signal;

a fourth inverter for inverting an output signal of the fifth AND gate; and

a sixth AND gate for ANDing an output signal of the non-inverting output terminal of the second D flip flop contained in the setup period determinator, the clock and an output signal of the fourth inverter, to output an output signal to the clock terminal of the third counter.

10. The robot apparatus as recited in claim 3, wherein the phase difference detector includes:

a clock counting unit for receiving two of the output signals from the first, the second and the third amplifying and filtering means and counting the number of second clocks during rising edges of the two output signals, to output each phase difference data;

a clear signal generating unit for receiving one signal of the two signals, to generate a clear signal, for clearing the clock counting unit; and

an interrupt signal generating unit, in response to the detection signal, for generating an interrupt signal for indicating a read timing of each phase difference data.

11. The robot apparatus as recited in claim 10, wherein the clear signal generating unit includes:

a first D flip flop having a clock terminal receiving one signal of the two signals and an input terminal coupled to a non-inverting terminal of the first D flip flop;

an inverter for inverting the one signal of the two signal; and

a first AND gate for ANDing an output signal of the inverter and an output signal of the non-inverting terminal of the D flip flop.

12. The robot apparatus as recited in claim 11, wherein the clock counting unit includes:

a second D flip flop having an input terminal coupled to a power terminal, a clock terminal coupled to one signal of the two signal, and a clear terminal coupled to the other signal of the two signal;

a second AND gate for ANDing the second clock, an output signal of the non-inverting output terminal of the second D flip flop, and an output signal of the non-inverting output terminal of the first D flip flop; and

a counter having a clock terminal coupled to an output terminal of the second AND gate and a clear terminal coupled to an output terminal of the first AND gate of the clear signal generating unit.

13. The robot apparatus as recited in claim 12, wherein the interrupt signal generating unit includes a third AND gate for ANDing one signal of the two signals, an output signal of the non-inverting output terminal of the first D flip flop contained in the clear signal generating unit, and the detection signal, to generate the interrupt signal.

14. The apparatus as recited in claim 1, wherein the sound receiving means includes at least four receivers, each being disposed in an equilateral triangle form.

15. The robot apparatus as recited in claim 1, further comprising a movement-direction detection means, wherein the movement-direction detection means includes an electronic compass for detecting a current movement direction of the robot apparatus by detecting an earth'"'"'s magnetic field and an analog-to-digital converter for converting an analog value detected from the electronic compass into a digital value.

16. The robot apparatus as recited in claim 15, wherein the electronic compass includes a first magnetic-field detector for detecting a X-direction of the earth'"'"'s magnetic field and a second magnetic-field detector for detecting a Y-direction of the earth'"'"'s magnetic field, the first and the second magnetic-field detectors being disposed in parallel to each other, each magnetic-field detector having two hole sensors coupled with ferrites, respectively.

17. The robot apparatus as recited in claim 15, wherein each magnetic-field detector includes:

a first hole sensor coupled between the power terminal and a ground terminal;

a second hole sensor coupled between the power terminal and the ground terminal; and

an amplifier having a non-inverting input terminal coupled to an output terminal of the first hole sensor, an inverting input terminal coupled to an output terminal of the second hole sensor through a first resistor, a second resistor and a capacitor being coupled in parallel between the inverting input terminal and an output terminal, a third resistor being serially coupled between the non-inverting input terminal and the ground terminal.

18. A method for operating a robot apparatus for detecting a sound signal outputted from a sound signal generating means to move to a position of the sound signal generating mean, wherein the sound signal has a specific pattern, the method comprising the steps of:

a) determining whether an operation mode is set up;

b) if the operation mode is not set up, setting up a standby mode to sense and trace a human body being within a predetermined distance;

c) if the operation mode is set up, determining kinds of operation mode; and

d) according to the operation mode, clearing a predetermined area by using an information of a plane structure obtained by searching and analyzing the plane structure, docking to a charger by searching the charger generating a sound signal when a battery of the robot is discharged, searching a sound source for generating a sound signal and performing a guard operation.

19. The method as recited in claim 18, wherein the step d) includes the steps of:

d1) if the operation mode is a plane structure search and analysis mode, searching and analyzing the plane structure by detecting a left, a right and a front distance;

d2) if the operation mode is a sound source search mode, search a sound direction to move to a sound direction, and searching and docking to the charger to charge the battery;

d3) if the operation mode is a guard operation mode, performing a guard operation after passing a predetermined time when an operation command is transmitted; and

d4) if the operation mode is an automatic clearing mode, clearing a predetermined area according to the information of the plane structure obtained through search and analysis of the plane structure.

20. The method as recited in claim 19, wherein the step d1) includes the steps of:

d11) performing an initial operation to search and move to a near wall, calculating a left, a right, and a front distance;

d12) after performing the initial operation, detecting a distance between a robot'"'"'s body and a left, a right, and a front distance, and a movement direction, to determine a current status of the robot apparatus by using an information associated with a detected distance and movement direction;

d13) setting up an operation by using a determined current status and a previous status;

d14) performing an operation which is set up at the step d13), and correcting a movement direction if the robot apparatus moves to an undesired direction; and

d15) after correcting the movement direction, according to whether or not the plane structure is a closed-loop by using a coverage distance and direction, preventing the robot apparatus from continuously moving around a specific object and repeating the step d12).

21. The method as recited in claim 20, wherein the step d15) includes the steps of:

d151) analyzing whether or not the plane structure to be searched is the closed-loop by using the coverage distance and direction;

d152) if it is determined that the plane structure is not the closed-loop, preventing the robot apparatus from continuously moving around the specific object; and

d153) if it is determined that the plane structure is the closed-loop, finishing an operation of the plane structure search and analysis.

22. The method as recited in claim 20, wherein the step d12) includes the steps of:

d121) detecting a front distance between the robot'"'"'s body and a wall disposed at a current movement direction;

d122) detecting a left distance between the robot'"'"'s body and the current movement direction;

d123) detecting a right distance between the robot'"'"'s body and a current movement direction;

d124) detecting a current movement direction to obtain an information used to change the robot'"'"'s movement status;

d125) determining a current movement distance status by using a detected front distance;

d126) determining a current movement distance status by using a detected left distance; and

d127) determining a current movement distance status by using a detected right distance.

23. The method as recited in claim 22, wherein each of the steps d125) to d127) includes the steps of:

d1251) determining whether or not the detected distance is smaller than a predetermined first reference distance;

d1252) if the detected distance is smaller than the predetermined first reference distance, determining the detected distance as a first near distance status;

d1253) if the detected distance is not smaller than the predetermined first reference distance, determining whether or not the detected distance is smaller than a predetermined second reference distance;

d1254) if the detected distance is equal to or larger than the predetermined first reference distance and smaller than the predetermined second reference distance, determining the detected distance as a second near distance status;

d1255) if the detected distance is equal to or larger than the predetermined first reference distance and not smaller than the predetermined second reference distance, determining whether or not the detected distance is equal to or larger than the predetermined second distance and smaller than a predetermined third reference distance;

d1256) if the detected distance is equal to or larger than the predetermined second reference distance and smaller than the predetermined third reference distance, determining the detected distance as a third near distance status; and

d1257) if the detected distance is equal to or larger than the predetermined second reference distance and not smaller than the predetermined third reference distance, determining the detected distance as a far distance status.

24. The method as recited in claim 20, wherein the step d14) includes the steps of:

d141) moving forward the robot apparatus by rotating a left motor and a right motor by a predetermined number in a forward direction, wherein the left and the right motors determine a moving speed and a direction of the robot apparatus;

d142) detecting a forward direction of the robot'"'"'s body by using the electronic compass mounted to the robot apparatus, to correct a movement direction when the robot apparatus collides with a ground and a obstacle; and

d143) determining whether an error value between the detected forward direction value at the step d142) and an original forward direction value is smaller than a predetermined minimum direction error value, to rotate the robot'"'"'s body to have the forward direction value equal to the original forward direction value.

25. The method as recited in claim 24, wherein the step d143) includes the steps of:

d1431) determining whether the error value between the detected forward direction value at the step d142) and the original direction forward direction value is smaller than the minimum direction error value;

d1432) if the error value is not smaller than the minimum direction error value at the step d1431), rotating the robot'"'"'s body to have the forward direction value to the original forward direction value; and

d1433) if the error value is smaller than the minimum direction error value at the step d1431), finishing a step of correcting the robot'"'"'s direction when the robot apparatus moves forward.

26. The method as recited in claim 20, wherein the step d14) includes the steps of:

d141) moving backward the robot apparatus by rotating a left motor and a right motor by a predetermined number in a backward direction, wherein the left and the right motors determine a moving speed and a direction of the robot apparatus;

d142) detecting a backward direction of the robot'"'"'s body to correct a movement direction when the robot apparatus collides with a ground and a obstacle; and

d143) determining whether an error value between a detected backward direction value at the step d142) and an original backward direction value is smaller than a predetermined minimum direction error value, to rotate the robot'"'"'s body to have the backward direction value equal to the original backward direction value.

27. The method as recited in claim 26, wherein the step d143) includes the steps of:

d1431) determining whether the error value between the detected backward direction value at the step d142) and the original direction backward direction value is smaller than the minimum direction error value;

d1432) if the error value is not smaller than the minimum direction error value at the step d1431), rotating the robot'"'"'s body to have the backward direction value equal to the original backward direction value; and

d1433) if the error value is smaller than the minimum direction error value at the step d1431), finishing a step of correcting the robot'"'"'s direction in a backward movement.

28. The method as recited in claim 20, wherein the step d14) includes the steps of:

d141) setting up an initial value of a forward/backward direction to ‘

0’

, and setting up the number of correction to ‘

0’

;

d142) increasing the number of correction one by one, detecting a current direction of the robot'"'"'s body to store a detected value of the current direction of the robot'"'"'s body, and calculating an angle difference between a target direction and the detected value of the current direction of the robot'"'"'s body;

d143) according as whether the angle difference is smaller than ‘

0’

, turning left or right the current movement direction;

d144) detecting the current direction of the robot'"'"'s body by using the electronic compass mounted to the robot apparatus, to correct an error of a turned direction of the robot'"'"'s body;

d145) according as whether a difference between a detected movement direction of the robot'"'"'s body and a target direction is smaller than a predetermined minimum-direction error value, calculating a difference between a stored previous movement direction of the robot'"'"'s body and a detected current movement direction, and determining whether or not a calculated difference is greater than the predetermined minimum-direction error value;

d146) if the calculated difference is greater than the predetermined minimum-direction error value, moving backward or forward to a predetermined minimum distance according as whether the forward/backward direction value is set to ‘

0’

; and

d147) if the calculated difference is nor greater than the minimum-direction error value, changing the forward/backward direction value, and giving an alarm depending on whether the number of correction is greater than a predetermined reference number of correction.

29. The method as recited in claim 28, wherein the step d143) includes the steps of:

d1431) determining whether the calculated angle difference is smaller than ‘

0’

;

d1432) if the calculated angle difference is smaller than ‘

0’

, changing the angle difference to a positive value greater than ‘

0’

;

d1433) turning right the robot'"'"'s body by rotating the left motor in a forward direction by the angle difference and rotating the right motor in a reverse direction by the angle difference; and

d1434) if the calculated angle difference is not smaller than ‘

0’

, turning left the robot'"'"'s body by rotating the left motor in a reverse direction by the angle difference and rotating the right motor in a forward direction by the angle difference.

30. The method as recited in claim 29, wherein the step d2) includes the steps of:

d21) setting an initial value of a negative-direction movement mode to ‘

0’

;

d22) detecting a movement direction and distances between the robot'"'"'s body and walls disposed at a left, right and front side, and determining a current status of the robot apparatus by using information on a detected distance and a movement direction;

d23) setting a sound-source search operation for searching a sound source according to a sound source search mode;

d24) according to a detour mode, performing a setup operation or moving to a direction of the sound source; and

d25) performing a battery charge for a predetermined time or setting a detour mode for detouring an obstacle disposed in a direction of the sound source, depending on a robot'"'"'s docking to the sound source.

31. The method as recited in claim 30, wherein the step d23) includes the steps of:

d231) determining whether the current movement status of the robot apparatus is the detour mode;

d232) if the current movement status is the detour mode, setting up commands with respect to a right-side priority mode for moving along a right-side wall and a left-side priority mode for moving along a left-side wall, respectively; and

d233) if the current movement status is not the detour mode, detecting a sound direction and a distance between the robot'"'"'s body and the sound source.

32. The method as recited in claim 31, wherein the step d232) includes the steps of:

d2321) determining whether the current status is the right-side priority mode or the left-side priority mode;

d2322) if the current status is the right-side priority mode, setting commands according to the right-side priority mode; and

d2323) if the current status is the left-side priority mode, setting commands according to the left-side priority mode.

33. The method as recited in claim 30, wherein the step d24) includes the steps of:

d241) determining whether the current status is the detour operation mode;

d242) if the current status is the detour operation mode, performing a setup operation;

d243) if the current status is not the detour mode, detecting a movement direction of the robot'"'"'s body by using the electronic compass;

d244) rotating the robot'"'"'s body to a direction of the sound source according to a detected movement direction of the robot'"'"'s body;

d245) moving forward in a direction of the sound source by a predetermined minimum distance; and

d246) if a distance between the robot'"'"'s body and the sound source is a near distance, stopping an operation of a forward movement to sense the sound source or obstacles disposed at a front side.

34. The method as recited in claim 33, wherein the step d246) includes the steps of:

d2461) after moving until a distance between a current position and the sound source becomes a minimum distance, detecting a front distance from the current position of the robot'"'"'s body;

d2462) determining whether the detected front distance is equal to the distance status;

d2463) if the detected front distance is equal to the distance status, stopping a forward movement of the robot apparatus; and

d2464) if the detected front distance is not equal to the distance status, repeating the step d245).

35. The method as recited in claim 34, wherein the step d25) includes the steps of:

d251) performing a sound source search and determining whether the robot apparatus is docked to the sound source;

d252) if it is determined that the robot apparatus is docked to the sound source, performing a battery charge for a predetermined time and detecting a current position of the sound source and storing a detected position of the sound source; and

d253) if it is determined that the robot apparatus is not docked to the sound source, setting a detour mode for detouring an obstacle disposed in a direction of the sound source, and repeating the step d2).

36. The method as recited in claim 35, wherein the step d251) includes the steps of:

d2511) determining whether the operation mode of the robot apparatus is the detour mode;

d2512) if it is determined that the operation mode is not the detour mode, performing an initialization of a detour operation, depending on whether the detected front distance is the near distance;

d2513) if it is determined that the operation mode is the detour mode, setting a current coordinate by adding a X coordinate of X and a previous X coordinate, depending on whether the movement distance of the robot apparatus is equal to or greater than a predetermined reference minimum distance required for a detour operation analysis;

d2514) if the current coordinate is smaller than a minimum value of X components, extracting the minimum value as a minimum coordinate of the current coordinate, and if the current coordinate is greater than a maximum value of X components, extracting the maximum value as a maximum coordinate of the current coordinate;

d2515) determining whether a current status of the robot apparatus is the right-side priority mode or the left-side priority mode by using an extracted minimum and the maximum values of the current coordinate;

d2516) if it is determined that the current status is the right-side priority mode, setting the sound-direction movement mode depending on whether a value of the current coordinate i s greater than a value corresponding to a half the minimum value of X axis; and

d2517) if it is determined that the current status is the left-side priority mode, setting the sound-direction movement mode depending on whether a value of the current coordinate is smaller than a value corresponding to a half the maximum value of X axis.

37. The method as recited in claim 36, wherein the step d2512) includes the steps of:

d25121) determining whether the detected front distance is equal to a distance between the robot apparatus and the sound source;

d25122) if it is determined that the detected front distance is equal to the distance between the robot'"'"'s body and the sound source, changing to a detour operation mode, and initializing a maximum and a minimum value of the X coordinate to ‘

0’

;

d25123) detecting the sound direction;

d25124) setting the detected sound direction as a coordinate of Y axis and a current position of the robot as a starting point; and

d25125) if it is determined that the detected front distance is not equal to the distance to the sound source, keeping on the sound direction movement mode and finishing the detour operation.

38. The method as recited in claim 36, wherein the step d2513) includes the steps of:

d25131) determining whether the movement distance of the robot apparatus is equal to or greater than the predetermined reference minimum distance;

d25132) if it is determined that the movement distance of the robot apparatus is equal to or greater than the predetermined reference minimum distance, setting a current coordinate by adding a X coordinate to a previous X coordinate, wherein the X coordinate is set according to the direction; and

d25133) if it is determined that the movement distance of the robot apparatus is smaller than the predetermined reference minimum distance, keeping on the sound direction movement mode and finishing a detour operation.

39. The method as recited in claim 36, wherein the step d2516) includes the steps of:

d25161) determining whether a value of the current coordinate is greater than a value corresponding to a half the minimum coordinate;

d25162) if the value of the current coordinate is greater than the value corresponding to the minimum coordinate, setting the sound direction movement mode; and

d25163) if the value of the current coordinate is not greater than the value corresponding to the minimum coordinate, keeping on the detour operation mode.

40. The method as recited in claim 39, wherein the step d2517) includes the steps of:

d25171) determining whether the value of the current coordinate is smaller than a value corresponding to a half the maximum coordinate;

d25172) if it is determined that the value of the current coordinate is smaller than the value corresponding to the half the maximum coordinate, setting the sound direction movement mode; and

d25173) if it is determined that the value of the current coordinate is not smaller than the value corresponding to the half the maximum coordinate, keeping on the detour operation mode.

41. The method as recited in claim 28, wherein the step d145) includes the steps of:

d1451) determining whether a difference between the calculated movement direction of the robot'"'"'s body and the target movement direction is smaller than a predetermined minimum-direction error value;

d1452) if the calculated difference is smaller than the minimum-direction error value, stopping a turning operation of the robot'"'"'s body;

d1453) if the calculated difference is not smaller than the minimum-direction error value, determining whether a difference between a detected value of the robot'"'"'s movement direction and a detected current value of the robot'"'"'s movement direction is greater than the minimum-direction error value;

d1454) if the calculated difference is greater than the minimum-direction error value, repeating the step d146); and

d1455) if the calculated difference is not greater than the minimum-direction error value, repeating the step d147).

42. The method as recited in claim 28, wherein the step d146) includes the steps of:

d1461) determining whether the forward/backward direction value is set to ‘

0’

;

d1462) if the forward/backward direction value is set to ‘

0’

, moving backward by the predetermined minimum distance; and

d1463) if the forward/backward direction value is not set to ‘

0’

, moving forward by the predetermined minimum distance and repeating the step d141).

43. The method as recited in claim 42, wherein the step d147) includes the steps of:

d1471) if the forward/backward direction value is ‘

1’

, changing the forward/backward direction value to ‘

0’

, and if the forward/backward direction value is ‘

0’

, changing the forward/backward direction value to ‘

1’

, thereby changing the current direction inversely;

d1472) determining whether the number of correction is greater than the reference number of correction;

d1473) if the number of correction is greater than the reference number of correction, re-setting the number of correction to ‘

0’

; and

d1474) if the number of correction is not greater than the reference number of correction, repeating the step d146).

44. The method as recited in claim 20, wherein the step d15) includes the steps of:

d151) determining whether a moving distance from the initial creation is greaser than a predetermined minimum distance required for analysis of the plane structure;

d152) if the moving distance is greater than the minimum distance, analyzing a coverage distance;

d153) extracting segments corresponding to components of the movement direction;

d154) by adding angles between extracted segments and a next segment, analyzing a closed-loop when an added angle is substantially 360°

;

d155) by analyzing whether a length of a long segment among the extracted segments is accorded with a directivity, if accorded, determining whether the plane structure is the closed-loop having the added angle of substantially 360°

; and

d156) in case of the closed-loop, finishing the step of analyzing the plane structure.

45. The method as recited in claim 19, wherein the step b3) includes the steps of:

b31) if a predetermined time is passed after an operation command for indicating a guard operation mode is transmitted, performing a guard operation mode;

b32) detecting a first front distance between a current position of the robot apparatus and an object disposed at a front side, a first left-side distance between the current position of the robot apparatus and an object disposed at a left side, and a first right-side distance between the current position of the robot apparatus and an object disposed at a right side;

b33) storing the first front distance, the first left-side distance and the first right-side distance;

b34) detecting a second front distance, a second left-side distance and a second right-side distance;

b35) comparing the first front distance, the first left-side distance and the right-side distance with the second front distance, the second left-side distance and the right-side distance, respectively, performing a first alarm depending on whether the robot apparatus is moved or not; and

b36) under the first alarm, analyzing an inputted voice data for identity, and performing an alarm depending on whether an analyzed voice data is a previously registered voice data.

46. The method as recited in claim 45, wherein the step b35) includes the steps of:

b351) checking whether the position of the robot apparatus is changed or not;

b352) if it is checked the position of the robot apparatus is changed, performing the first alarm;

b353) if it is checked at the step b352) that the position of the robot apparatus is not changed, checking whether the human body is detected;

b354) if it is checked at the b353) that the human body is not detected, repeating the step b34); and

b355) if it is checked at the step b353) that the human body is detected, repeating the step b352).

47. The method as recited in claim 46, wherein the step b36) includes the steps of:

b361) under the first alarm, analyzing the inputted voice data for identity;

b362) checking whether or not the analyzed voice data is a previous registered voice data;

b363) if it is checked that the inputted voice data is not the previously registered voice data, operating the alarm; and

b364) if it is checked that the inputted voice data is the previously registered voice data, performing the step b32).

48. The method as recited in claim 18, wherein the step b) includes the steps of:

b1) detecting a sound signal generated from an exterior, and checking whether or not the generated sound signal is detected;

b2) if the generated sound signal is detected, moving toward a sound source generating the sound signal;

b3) if the generated sound signal is not detected, checking whether or not the human body is detected;

b4) if the human body is detected, sensing a direction of the human body and moving to the direction of the human body;

b5) if the human body is not detected, checking a scan number performed to sense the human body and checking the sense of the human body in the range of 360°

depending on whether the scan number is greater than a predetermined reference scan number;

b6) if the human body is detected at the step b5), repeating the step b4); and

b7) if the human body is not detected at the step b5), moving to a wall or a corner after a predetermined time from the sense of the human body, and then maintaining a standby status.

49. The method as recited in claim 48, wherein the step b4) includes the steps of:

b41) checking whether the sensed direction of the human body is more than two;

b42) if it is checked that the sensed direction of the human body is more than two, moving to a human body sensed in a direction closest to a direction of previous movement or track; and

b43) if it is checked that the sensed direction of the human body is one, moving to the sensed direction.

50. The method as recited in claim 48, wherein the step b5) includes the steps of:

b51) checking a scan number performed to sense a human body and determining whether or not a checked scan number is greater than the predetermined reference scan number;

b52) if it is determined that the checked scan number is greater than the predetermined scan number, checking whether a human body is detected in the range of 360°

;

b53) if thie human body is detected at the step b52), repeating the step b4);

b54) if the human body is detected at the step b52), repeating the step b7); and

b55) if it is determined that the checked scan number is not greater than the predetermined reference scan number, repeating the step b3).

51. The method as recited in claim 50, wherein the step b7) includes the steps of:

b71) determining whether or not the predetermined time is passed after detection of the human body;

b72) if it is determined that the predetermined time is passed, moving to a wall or a corner and then maintaining a standby status; and

b73) if it is determined that the predetermined time is not passed, repeating the step b1).

52. The method as recited in claim 18, if added angles between segments obtained through a plane structure analysis is substantially less than 360°

, turning as much as 90° and

then moving forward until a front distance becomes a predetermined reference near distance and initializing an entire system.

53. The method as recited in claim 18, wherein a portion to which a sensor for detecting a human body is mounted is rotated, to thereby detect and trace a motionless human body.

54. The method as recited in claim 18, wherein, if a front distance, a left-side distance and a right-side distance are a near distance, and a sum of the left-side distance and the right-side distance is greater than a minimum space required to rotate the robot'"'"'s body, the robot is turned left as much as 90°

, and

wherein, if the front distance, the left-side distance and the right-side distance are a near distance and a sum of the left-side distance and the right-side distance is not greater than a minimum space required to rotate the robot apparatus, a backward movement operation is set.

55. The method as recited in claim 54, wherein the front distance and the left-side distance are the near distance and the right-side distance is a far distance, turning a right as much as 90°

and then setting a forward movement operation.

56. The method as recited in claim 55, wherein, if the front distance is a near distance, the left-side distance is a far distance and the right-side distance is a near distance, turning left as much as 90°

and setting a forward movement operation.

57. The method as recited in claim 56, wherein, if the front distance is a near distance, the left-side distance is a far distance and the right-side is a far distance, and if a previous operation is a turning left as much as 90°

, turning left as much as 90° and

setting a forward movement operation,

wherein, if the front distance, the left-side distance and the right-side distance are far distances, and if a previous operation is a turning right as much as 90° and

a moving forward, turning left as much as 90° and

then setting a forward movement operation, and

wherein, if a previous front distance, a previous left-side distance and a previous right-side distance are far distances, if a previous operation is not a turning right as much as 90° and

not a moving forward, turning right as much as 90° and

then setting a forward movement operation.

58. The method as recited in claim 57, wherein, if a current front distance is a far distance, a left-side distance is a near distance and a right-side distance is a near distance, and if a previous operation is a backward movement or a turning left as much as 90°

, and if a sum of the current left-side distance and the current right-side distance is greater than a minimum space required to rotate the robot apparatus, setting a turning left as much as 90°

,

wherein, if the current front distance is a far distance, the left-side distance is a near distance and a right-side distance is a near distance, and if a previous operation is not a turning left as much as 90° and

the previous operation is a backward movement operation, setting a backward movement operation, and

wherein, if the current front distance is a far distance, a left-side distance is a near distance and a right-side distance is a near distance, and if a previous operation is not a backward movement operation, setting a forward movement operation.

59. The method as recited in claim 58, wherein, if the current front distance is a far distance, a left-side distance is a near distance and a right-side distance is a far distance, and if a previous operation is a backward movement operation, setting a left as much as 90°

, and

wherein, if the current front distance is a far distance, the current left distance is a near distance and the current right distance is a far distance, and if a previous operation is not a backward movement operation, turning right as much as 90° and

then setting a forward movement operation.

60. The method as recited in claim 59, wherein, if the current front distance and the current left-side distance are far distances and a right-side distance is a near distance, and if a previous operation is a backward movement operation, setting a turning left as much as 90°

,

wherein, if the robot apparatus is able to rotate in the current right-side distance and a previous front distance and a previous left-side distance are far distances and the right-side distance is a near distance, and if a previous operation is a forward movement operation, turning left as much as an angle corresponding to an inverse tangent of a value obtained by dividing a movement distance by a difference between a predetermined minimum unit angle or a current right distance and a previous right distance, and then setting a forward movement operation, and

wherein, if the current right-side distance of the robot apparatus is out of a distance required for the robot apparatus to be rotated, and if a previous front distance is farther than the distance required for the robot apparatus to be rotated, if the left-side distance is a far distance, the right-side distance is a near distance and a previous operation is a forward movement operation, turning right as much as an angle corresponding to an inverse tangent of a value obtained by dividing a movement distance by a difference between a predetermined minimum unit angle or a current right distance and a previous right distance, and then setting a forward movement operation.

61. The method as recited in claim 60, wherein, if the current front distance, the current left-side distance and the right-side distance are far distances and if a previous operation is a turning left as much as 90°

for four successive times, setting a forward movement operation,

wherein, if the current front distance, the current left-side distance and the right-side distance are far distances, and if the previous operation is a turning right for four successive times, setting a forward movement operation,

wherein, if the previous front distance, the previous left-side distance and the previous right-side distance are far distances, and if the previous operation is a forward movement operation, setting a forward movement operation,

wherein, if the previous front distance, the previous left-side distance and the previous right-side distance are far distances, and if the previous movement is not a forward movement operation, and if the previous movement is a backward movement or a turning left as much as 90°

, setting a turning left as much as 90°

, and

wherein, if the previous front distance, the previous left-side distance and the previous right-side distance are far distances, and if the previous operation is not a forward movement, a backward movement or a turning left as much as 90°

, setting a turning right as much as 90° and

then setting a forward movement operation.

62. The method as recited in claim 18, wherein, if the current front distance, the left-side distance and the right-side distance are near distances, and if a sum of the left-side distance and the right-side distance is greater than a minimum space required for the robot apparatus to be rotated, setting a turning right as much as 90°

, and

wherein, if the current front distance, the current left-side distance, and the current right-side distance are near distances, and if the sum of the left-side distance and the right-side distance is not greater than the minimum space, setting a backward movement operation.

63. The method as recited in claim 62, wherein, if the current front distance and the left-side distance are near distance and the current right-side distance is a far distance, setting a turning right as much as 90°

and then setting a forward movement operation.

64. The method as recited in claim 63, wherein, if the current front distance, the current left-side distance and the right-side distance are near distance, setting a turning left as much as 90°

and then setting a forward movement operation.

65. The method as recited in claim 64, wherein, if the current front distance is a near distance, the current left-side distance is a far distance and the current right-side distance is a far distance, and if a previous operation is a turning right as much as 90°

, setting a turning right as much as 90° and

then setting a forward movement operation, and

wherein, if the current front distance is a near distance, the current left-side distance is a far distance and the current right-side distance is a far distance, and if a previous operation is not a turning right as much as 90°

, or if the previous front distance, the left-side distance and the right-side distance are far distances and if the previous operation is not a forward movement operation, turning left as much as 90° and

setting a forward movement operation.

66. The method as recited in claim 65, wherein, if the current front distance is a far distance, the current left-side distance is a near distance and the right-side distance is a near distance, and if a previous operation is a backward movement operation or a turning right as much as 90°

, and if a sum of the current left-side distance and the right-side distance is greater than a minimum space required for the robot apparatus to be rotated, setting a turning right as much as 90°

,

wherein, if the current front distance is a far distance, the current left-side distance is a near distance and the right-side distance is a near distance, and if the previous operation is a backward movement operation, setting a backward movement operation, and

wherein, if the current front distance is a far distance, the left-side distance is a near distance and the right-side distance is a near distance, and if the previous operation is not a backward movement operation, setting a forward movement operation.

67. The method as recited in claim 66, wherein, if the current front distance is a far distance, the left-side distance is a near distance and the right-side distance is a far distance, and if the previous operation is a backward movement operation, setting a turning right as much as 90°

,

wherein, if the current front distance is a far distance, the left-side distance is a near distance and the right-side distance is a far distance, and if the robot apparatus is unable to rotate in the current left-side distance and a previous front distance is a far distance and a left-side distance is a near distance, and the right-side distance is a far distance, and if the previous operation is a forward movement operation, turning right as much as an angle corresponding to an inverse tangent of a value obtained by dividing a movement distance by a difference between a predetermined minimum unit angle or a current right distance and a previous right distance, and then setting a forward movement operation,

wherein, if the current right-side distance of the robot apparatus is out of a distance required for the robot apparatus to be rotated, and if a previous front distance is a far distance, a previous left-side distance is a near distance and the previous right-side distance is a far distance and a previous operation is a forward movement operation, turning left as much as an angle corresponding to an inverse tangent of a value obtained by dividing a movement distance by a difference between a predetermined minimum unit angle or a current right distance and a previous right distance, and then setting a forward movement operation, and

wherein, if the current right-side distance of the robot apparatus is out of a distance required for the robot apparatus to be rotated, and if a previous front distance is a far distance, a previous left-side distance is a near distance and the previous right-side distance is a far distance and a previous operation is not a forward movement operation, setting a forward movement operation.

68. The method as recited in claim 67, wherein, if the current front distance and the left-side distance are far distances, and the right-side distance is a near distance, and if a previous operation is a backward movement operation, setting a turning right as much as 90°

, and

wherein, if the current front distance and the left-side distance are far distances and the right-side distance is a near distance, and if the previous operation is not a backward movement operation, turning left as much as 90° and

then setting a forward movement operation.

69. The method as recited in claim 68, wherein, if the current front distance is a near distance, the left-side distance and the right-side distance are far distances, and if the previous operation is a turning right as much as 90°

in four successive times, setting a forward movement operation,

wherein, if the current front distance, the left-side distance and the right-side distance are far distances, and if the previous operation is a turning left as much as 90°

in four successive times, setting a forward movement operation,

wherein, if the previous front distance, the previous left-side distance and the previous right-side distance are far distances, and if the previous operation is a forward movement operation, setting a forward movement operation,

wherein, if the previous front distance, the left-side distance and the previous right-side distance are far distances, and if the previous operation is a backward movement operation or a turning right as much as 90°

, setting a turning right as much as 90°

, and

wherein, if the previous front distance, the previous left-side distance and the previous right-side distance are far distances, and if the previous operation is not a backward movement operation or a turning right, turning left as much as 90° and

then setting a forward movement operation.