A system for preventing overflow of a toilet includes a sensor, a processor and an actuator. The sensor senses a parameter caused by fluid dynamics within the toilet during a flush cycle. The parameter may involve vibration, sound, pressure, fluid flow rate or other detectible characteristics of the toilet. The processor uses information regarding the parameter that is gathered by the sensor to evaluate the condition of the flush cycle to determine if an impeded flush condition exists. In the event of an impeded flush condition, the processor directs the actuator to close a valve, which may be the toilet flapper valve in some embodiments. Also disclosed are methods for preventing toilet overflow, detecting an impeded flush condition and calibrating the system.

An improved fluid level verification apparatus with an integral, internal source of illumination that is powered by an integral, internal energy source and is activated by a motion sensor or any other sensor commonly known in the art to detect the presence of a person in dark or dimly lit environments. The preferred light source is a light emitting diode (LED). A second embodiment of the integral, internal source of illumination that is powered by an integral, internal energy source and is activated by a motion sensor or any other sensor commonly known in the art to detect the presence of a person in dark or dimly lit environments is applied to a fluid reservoir tank.

In a liquid level monitor for use with a liquid container of a liquid-consuming device, a light source transmits a light beam into the liquid container at a non-normal angle of incidence respective to a wall of the liquid container. A photodetector is positioned in the path of one of (i) the light beam after passing through the liquid container when the light beam is not refracted by liquid in the liquid container and (ii) the light beam after passing through the liquid container when the light beam is refracted by liquid in the liquid container. In another approach, the sensor for detecting empty includes a vibrator and a vibration sensor, and an electronic processor is programmed to determine whether the liquid container is empty of liquid based on the detected vibration of the liquid container.

Methods, apparatuses, and storage mediums are provided for detecting water shortage for a humidifier. The method includes: obtaining a water level parameter of a water tank; determining a water level state of the water tank according to the water level parameter. When the water level state of the water tank is a water shortage state, energizing a valve connected to a water box so that water can be added to the water tank through the valve. A number of times of energizing the valve is recorded. When the number of times of energizing the valve exceeds a first preset number of times as well as when the water level state of the water tank determined every time after energization of the valve is the water shortage state, confirming that the water box is short of water.

An embodiment includes a combine including a feeder housing for receiving harvested crop, a separating system for threshing the harvested crop to separate grain from residue, a grain tank for storing the separated grain, a grain tank level sensor for detecting a level of grain in the grain tank, an inclination sensor for detecting inclination of the combine, and a controller that controls the combine. The controller configured to receive the grain tank level from the grain tank level sensor, receive an inclination value from the inclination sensor, adjust the grain tank level based on the inclination value, and alert an operator of the adjusted grain tank level.

A method of measuring a height of a fuel in an aircraft fuel tank (21)b including illuminating the fuel in the aircraft fuel tank and detecting reflected light from the fuel. Optical coherence tomography is used to determine the height of a surface of fuel in the fuel tank. An apparatus (30) is used to measure a height of a surface of fuel in an aircraft fuel tank, and an aircraft fuel tank system with a fuel tank and an apparatus for measuring a height of a surface of fuel in the aircraft fuel tank.

A guide robot includes a lower module includes a wheel and a motor provided inside the lower module, and an upper module disposed at an upper portion of the lower module and including a trash can assembly and a display unit. The upper module includes a body part coupled to the upper portion of the lower module and a head part rotatably coupled to an upper portion of the body part. The body part includes a front case forming a front outer appearance of the body part and including the trash can assembly provided inside the front case, and a rear case forming a rear outer appearance of the body part and including the display unit. A garbage insertion part is provided at a portion of the front case corresponding to an upper portion of the trash can assembly to insert garbage into the trash can assembly.

A washer fluid level indication system of a vehicle determines a present volume of washer fluid present within a washer fluid reservoir. A flowrate module is configured to determine a volume of washer fluid dispensed based on a measured voltage applied to a washer fluid pump and a predetermined volumetric flowrate of dispensing washer fluid calibrated based on a predetermined voltage. The flowrate module is configured to subtract the volume of washer fluid dispensed from the present volume. A level module is configured to determine a present level of washer fluid within the washer fluid reservoir based on the present volume and a predetermined maximum volume of the washer fluid reservoir. A display control module is configured to display the present level of washer fluid within the washer fluid reservoir using a washer level indicator.

A system for preventing overflow of a toilet includes a sensor, a processor and an actuator. The sensor senses a parameter caused by fluid dynamics within the toilet during a flush cycle. The parameter may involve vibration, sound, pressure, fluid flow rate or other detectible characteristics of the toilet. The processor uses information regarding the parameter that is gathered by the sensor to evaluate the condition of the flush cycle to determine if an impeded flush condition exists. In the event of an impeded flush condition, the processor directs the actuator to close a valve, which may be the toilet flapper valve in some embodiments. Also disclosed are methods for preventing toilet overflow, detecting an impeded flush condition and calibrating the system.

A washer fluid level indication system of a vehicle determines a present volume of washer fluid present within a washer fluid reservoir. A flowrate module is configured to determine a volume of washer fluid dispensed based on a measured voltage applied to a washer fluid pump and a predetermined volumetric flowrate of dispensing washer fluid calibrated based on a predetermined voltage. The flowrate module is configured to subtract the volume of washer fluid dispensed from the present volume. A level module is configured to determine a present level of washer fluid within the washer fluid reservoir based on the present volume and a predetermined maximum volume of the washer fluid reservoir. A display control module is configured to display the present level of washer fluid within the washer fluid reservoir using a washer level indicator.