초록 ▼

A navigational control system for an autonomous robot includes a transmitter subsystem having a stationary emitter for emitting at least one signal. An autonomous robot operating within a working area utilizes a receiving subsystem to detect the emitted signal. The receiver subsystem has a receiver

A navigational control system for an autonomous robot includes a transmitter subsystem having a stationary emitter for emitting at least one signal. An autonomous robot operating within a working area utilizes a receiving subsystem to detect the emitted signal. The receiver subsystem has a receiver for detecting the emitted signal emitted by the emitter and a processor for determining a relative location of the robot within the working area upon the receiver detecting the signal.

대표청구항 ▼

What is claimed is: 1. A navigational control system for a mobile robot operating within a working area, the navigational control system comprising: a transmitter disposed within a working area and comprising a stationary emitter configured to direct first and second signals, modulated to be differ

What is claimed is: 1. A navigational control system for a mobile robot operating within a working area, the navigational control system comprising: a transmitter disposed within a working area and comprising a stationary emitter configured to direct first and second signals, modulated to be different from one another, onto a remote surface above the working area, such that the first and second signals are reflected from spaced apart positions on the remote surface; and a receiving subsystem disposed on the mobile robot and comprising: a receiver installed at a top surface of the mobile robot and directed generally upward, the receiver including at least four discrete photodiodes arranged to face in different directions and configured to generate respective response signals responsive to the reflected signals; and a processor connected to the receiver and configured to determine a first angle associated with the first reflected signal, from relative amplitudes of the response signals from the photodiodes in response to the first signal as reflected off of the remote surface, to determine a second angle associated with the second reflected signal, from relative amplitudes of the response signals from the photodiodes in response to the second signal as reflected off of the remote surface, and to determine a location of the robot within the working area relative to the reflected signals, based on the first and second determined angles; wherein the photodiodes are angularly spaced to face in different directions about the receiver so as to detect one or both of the reflected signals in various positions within the working area. 2. The navigational control system of claim 1, wherein the emitter sequentially emits the first and second signals as coded signals. 3. The navigational control system of claim 1, wherein the receiver comprises four photodiodes oriented orthogonally to each adjacent photodiode, each photodiode adapted to detect at least one of the first or second signals reflected from the remote surface. 4. The navigational control system of claim 1, wherein the receiver comprises four photodiodes each arranged to at least partially face one of four substantially orthogonal travel directions of the robot. 5. The navigational control system of claim 1, wherein each photodiode is arranged at an angle with respect to an adjacent photodiode. 6. The navigational control system of claim 1, wherein the receiver comprises five photodiodes. 7. The navigational control system of claim 6, wherein the one of the photodiodes is oriented substantially orthogonally to each of the four other photodiodes. 8. The navigational control system of claim 5, wherein at least one of the photodiodes is oriented in a direction corresponding to a reference direction of travel of the robot. 9. The navigational control system of claim 1, wherein the processor further comprises a navigational algorithm. 10. The navigational control system of claim 9, wherein the processor directs a movement of the robot within the working area based on input from the receiver. 11. The navigational control system of claim 1, wherein the processor determines the relative position of the robot at least in part on at least one of an elevation and an azimuth of each detected signal. 12. The navigational control system of claim 1, wherein the transmitter is located on a robot docking station within the working area, and the docking station emitting a signal onto a remote surface above the working area, the receiver being responsive to the emitted docking station signal as reflected off of the remote surface. 13. The navigational control system of claim 1, wherein the at least one signal comprises light having at least one of a visible wavelength and an infrared wavelength. 14. The navigational control system of claim 1, wherein the discrete photodiodes detect the first and second signals emitted by the transmitter as reflected energy bouncing off a diffuse ceiling surface. 15. A method of control for a mobile robot operating within a working area, the method comprising: transmitting directed first and second signals, modulated to be different from one another, onto a remote surface above the working area, such that the first and second signals are reflected from spaced apart positions on the remote surface; detecting the first and second signals as reflected off of the remote surface using an upwardly directed receiver of the mobile robot, the receiver including at least four discrete photodiodes arranged to face in different directions and configured to generate respective response signals responsive to the reflected signals; determining a first angle associated with the first reflected signal, from relative amplitudes of the response signals from the photodiodes in response to the first signal as reflected off of the remote surface; determining a second angle associated with the second reflected signal, from relative amplitudes of the response signals from the photodiodes in response to the second signal as reflected off of the remote surface; and determining a location of the robot in the working area relative to the reflected signals, based on the first and second determined angles; wherein the photodiodes are angularly spaced to face in different directions about the receiver so as to detect one or both of the reflected signals in various positions within the working area. 16. The method of claim 15, further comprising directing a movement of the robot within the working area, the movement based at least in part upon the determined location of the robot within the working area. 17. The method of claim 15, further comprising storing the location of the robot in memory. 18. The method of claim 17, further comprising comparing the location of the robot to a stored location. 19. The method of claim 18, further comprising directing a movement of the robot within the working area, the movement based at least in part on the stored location. 20. The method of claim 15, wherein the location of the robot is based at least in part on at least one of an elevation and an azimuth of the detected signal. 21. The method of claim 17, further comprising creating a map of the working area based on the locations of the robot as the robot maneuvers about the working area. 22. The method of claim 15, further comprising: maneuvering the robot away from a base station about a plurality of working areas, each working area having a corresponding transmitter configured to emit a coded signal; associating each received coded signal with the corresponding working area; storing a travel order of encountered working areas; monitoring a power level of the robot; when the robot power level is below a threshold power level, maneuvering the robot through the encountered working areas in reverse travel order back to the docking station. 23. The method of claim 22, further comprising maneuvering the robot away from the docking station through the previously encountered working areas according to the travel order. 24. The method of claim 15, further comprising arranging each photodiode of the receiver to at least partially face one of four substantially orthogonal travel directions of the robot. 25. The method of claim 15, further comprising arranging each photodiode of the receiver orthogonally to each adjacent photodiode, each photodiode adapted to detect at least one of the first or second signals reflected from the remote surface. 26. The navigational control system of claim 12, wherein the processor is configured to maneuver the robot in response to the received docking station signal as reflected off of the remote surface. 27. The navigational control system of claim 12, wherein the processor is configured to locate the docking station for docking in response to the received docking station signal as reflected off of the remote surface. 28. The navigational control system of claim 1, wherein the processor executes operations comprising: maneuvering the robot away from a docking station about a plurality of working areas, each working area having a corresponding transmitter configured to emit a coded signal, the processor associating the coded signal with the corresponding working area; storing a travel order of encountered working areas; monitoring a power level of the robot; when the robot power level is below a threshold power level, maneuvering the robot through the encountered working areas in reverse travel order back to the docking station. 29. The navigational control system of claim 28, wherein the operations further comprise maneuvering the robot away from the docking station through the previously encountered working areas according to the travel order. 30. The navigational control system of claim 1, wherein the processor is configured to create a map of the working area based on the relative locations of the robot as the robot maneuvers about the working area. 31. The navigational control system of claim 1, wherein the first and second signals are modulated to be different from one another by modulating the signals at different frequencies. 32. The navigational control system of claim 1, wherein the first and second signals are modulated to be different from one another by pulsing the signals with different codes. 33. The method of claim 15, wherein the first and second signals are modulated to be different from one another by modulating the signals at different frequencies. 34. The method of claim 15, wherein the first and second signals are modulated to be different from one another by pulsing the signals with different codes. 35. A mobile robot comprising: drive components that move the robot within a working area; and a navigational control receiving subsystem comprising: a receiver installed at a top surface of the mobile robot, the receiver including at least four independent photodiodes arranged to face in different directions and each responsive to first and second reflected signals at spaced apart positions on a remote surface above the working area, the first and second signals modulated to be different from one another; and a processor connected to the receiver and configured to determine a first angle associated with the first reflected signal, by comparing signals from the four independent photodiodes in response to the first reflected signal, to determine a second angle associated with the second reflected signal, by comparing signals from the four independent photodiodes in response to the second reflected signal, and determine a location of the robot within the working area relative to the reflected signals, based on the first and second determined angles; wherein the at least four independent photodiodes are angularly spaced to face in different directions about the receiver so as to detect one or both of the reflected signals in various positions within the working area.