Abstract: A pool cleaning robot that may include a filtering unit for filtering fluid that passes through the filtering unit; a calorimetric sensor for sensing a cleanliness related parameter of the filtering unit while the pool cleaning robot is submerged in the fluid; and a controller that is configured to at least assist in determining, based on the cleanliness related parameter of the filtering unit, a cleanliness of the filtering unit.

Abstract: A pool cleaning robot that may include a filtering unit for filtering fluid that passes through the filtering unit; a calorimetric sensor for sensing a cleanliness related parameter of the filtering unit while the pool cleaning robot is submerged in the fluid; and a controller that is configured to at least assist in determining, based on the cleanliness related parameter of the filtering unit, a cleanliness of the filtering unit.

Abstract: Provided is a system for measuring milk flow at a milking installation. A first electrode and a second electrode are positioned inside a milk conduit across which a fixed voltage is applied. Milk flowing in the conduit forms a resistive element between the electrodes. Electric current in the milk between the two electrodes is detected by an ammeter, amplified by an amplifier, and then stored in a memory. A processor is configured to determine the current flow rate of milk in the conduit between the electrodes. The processor is further configured to determine the time averaged value of the amplified current over a recent time window. If the determined average is not within a predetermined range, the processor determines a gain of the amplifier that would have brought this time average into the predetermined range. The processor then resets the gain of the amplifier to the determined gain in order to bring the time average of the amplified current over subsequent time windows into the predetermined range.