Robot navigation

1. A directed beam emitter system for robot navigation, comprising:

at least one light beam emitter that emits a modulated directed light beam of a first modulation; and

at least one omnidirectional diffuse light region emitter that emits a modulated diffuse light region of a second modulation,

the modulated directed light beam and the modulated diffuse light region overlapping in a plane parallel to ground level such that a light beam receiver on a robot may detect either one or both of the modulated directed light beam and the modulated diffuse light region; and

wherein the light beam emitter is responsive to a control system used to control one or more light beam emitters.

2. The directed beam emitter system of claim 1 , wherein the modulated directed light beam is a modulated signal in an infrared frequency.

3. The directed beam emitter system of claim 1 , wherein the light beam emitter is responsive to a control system that communicates directly with one or more light beam emitters allowing a cycling of work spaces.

4. The directed beam emitter system of claim 1 , wherein the light beam emitter is responsive to a robot that sends a signal to the light beam emitter to turn the light beam emitter on.

5. The directed beam emitter system of claim 1 , further comprising a retroreflector for reflecting the directed light beam.

6. The directed beam emitter system of claim 5 , wherein the modulated directed light beam is reflected by the retroreflector back to a detector on the light beam emitter.

7. The directed beam emitter system of claim 6 , wherein the light beam emitter emits a light beam of a third modulation upon interruption of the light beam of the first modulation.

8. The directed beam emitter system of claim 5 , further comprising additional retroreflectors defining a series of work areas.

9. The directed beam emitter system of claim 5 , further comprising additional retroreflectors defining a series of obstacles.

10. The directed beam emitter system of claim 1 , further comprising:

a detector on the light beam emitter,

a retroreflector for directing the modulated light beam back to the light beam emitter; and

an electromagnetic signal emitter that emits radio, x-ray or microwave signals to the robot in response to interruption of the light beam.

11. A retroreflector navigation system for robot navigation, comprising:

a robot having a light beam receiver oriented in a manner to have an omnidirectional field of view;

at least one omnidirectional diffuse light region emitter that emits a modulated diffuse light region,

the omnidirectional modulated diffuse light region positioned in a plane parallel to ground level such that a light beam receiver on the robot is in the same plane as the omnidirectional modulated diffuse light region; and

a series of retroreflectors for reflecting modulated directed light beams to define a series of work areas.

12. The retroreflector navigation system of claim 11 , wherein the omnidirectional modulated diffuse light region is modulated in an infrared frequency.

13. The retroreflector navigation system of claim 11 , wherein the light beam emitter is responsive to a robot that sends a signal to the light beam emitter to turn the light beam emitter on.

14. The retroreflector navigation system of claim 11 , further comprising a detector on the omnidirectional light region emitter and wherein a modulated directed light beam of a second modulation is reflected by a retroreflector back to the omnidirectional light region emitter.

15. The retroreflector navigation system of claim 14 , wherein the omnidirectional light region emitter emits a light beam of a third modulation upon interruption of the light beam of the second modulation.

16. The retroreflector navigation system of claim 11 , wherein the series of retroreflectors defines an obstacle.

17. The retroreflector navigation system of claim 11 , further comprising:

a detector on the omnidirectional light region emitter; and

an electromagnetic signal emitter that emits radio, x-ray or microwave signals to the robot in response to interruption of a directed light beam detected by the detector.