Pressure sensor diaphragm for pool cleaning robot

A method for evaluating a cleanliness of a filter of a pool cleaning robot, the method comprises:

• sensing, by a gas pressure sensor of a sensing module of a pool cleaning robot, a gas pressure within a second space of the sensing module;
• wherein the sensing module further comprises a first space and a diaphragm;
• wherein the diaphragm seals the second space and separates the first space from the second space;
• wherein the diaphragm, via the first space, is fluidly coupled to a filtering unit of the pool cleaning robot;
• wherein the diaphragm is configured to define a gas pressure within the second space as a function of, at least, a fluid pressure within the first space;
• receiving, by a processor of a pool cleaning robot, information about the gas pressure within the second space;
• and
• determining, by the processor, a cleanliness level of a filtering unit of the pool cleaning robot, based at least on the gas pressure within the second space.