Pool cleaning robot and a method for cleaning a pool

1. A pool cleaning robot, comprising: a ballast tank for controlling a buoyancy of the pool cleaning robot; at least one cleaning element for cleaning debris from an underwater surface of a pool while the pool cleaning robot hovers over the underwater surface; a propulsion module that is configured to propel the pool cleaning robot; and a steering module that comprises a rudder and diving planes.

2. The pool cleaning robot according to claim 1 wherein the underwater surface is positioned above a bottom of the pool and wherein the pool cleaning robot comprises a navigation module for navigating the pool cleaning robot to a hovering position above the underwater surface.

3. The pool cleaning robot according to claim 2 wherein the pool cleaning robot is configured to reach the hovering position without climbing on any pool structural element that leads to the underwater surface.

4. The pool cleaning robot according to claim 1 comprising a fluid conduit for selectively filling the ballast tank with fluid; wherein the fluid conduit has an opening that is positioned at a lower part of the submersible pool cleaner.

5. The pool cleaning robot according to claim 1 comprising a fluid conduit for selectively filling the ballast tank with fluid; wherein the fluid conduit has an opening that is positioned at an upper part of the submersible pool cleaner.

6. The pool cleaning robot according to claim 1 comprising:

a skimmer that is positioned at a lower part of the submersible pool cleaner; and

a fluid conduit for selectively filling the ballast tank with fluid; wherein the fluid conduit fluidly couples the skimmer to the ballast tank.

7. The pool cleaning robot according to claim 6 wherein the ballast tank is configured to suck fluid through the fluid conduit when the pool cleaning robot is in an inverted position.

8. The pool cleaning robot according to claim 7 when the pool cleaning robot is configured to be in the inverted position when the skimmer collects floating dirt that floats on a fluid of the pool.

9. The pool cleaning robot according to claim 1 wherein the at least one cleaning element comprises one or more bottom brushes that are coupled to a bottom of a housing of the cleaning robot and one or more side suction brushes that are coupled to sides of the housing.

10. The pool cleaning robot according to claim 1 wherein the at least one cleaning element comprises one or more bottom brushes that are coupled to a bottom of a housing and one or more balancing wheels that are spaced apart from the one or more bottom brushes.

11. The pool cleaning robot according to claim 1 comprising at least one sensor for sensing debris.

12. The pool cleaning robot according to claim 1 wherein the underwater surface is an upper surface of an underwater stair.

13. The pool cleaning robot according to claim 1 wherein the propulsion module comprises a jet generator that is configured to generate one or more jets for propelling the pool cleaning robot.

14. The pool cleaning robot according to claim 1 wherein the propulsion module comprises multiple impellers, at least two impellers are oriented in relation to each other.

15. The pool cleaning robot according to claim 1 wherein the propulsion module comprises a first jet generator and a second jet generator; wherein the first jet generator is configured to generate first fluid jets while the pool cleaning robot propagates towards the underwater surface; wherein the second jet generator is configured to generate second fluid jets while the pool cleaning robot hovers over the underwater surface; wherein the first fluid jets are stronger than the second fluid jets.

16. The pool cleaning robot according to claim 1 comprising an induction-based electrical charging module.