Abstract: An aeroponic plant-growth system includes growth space and a control unit that may be assembled using factory made modules. The growth space includes layers at different heights, and each layer includes plant holders and misters positioned to apply a mist to roots of plants in the plant holders. The control unit employs a controller to execute a program that operates a liquid supply system to provide liquid flows to the misters in the layers. Each of the liquid flows may be regulated according to the height of the layers.

Abstract: A sensor, such as a hydrostatic water level sensor, includes a pressure sensor, a vent, a vent tube connecting the vent to the pressure sensor, and a fabric covering the vent. The pressure sensor is submersible in a liquid to be measured and the vent is configured to be outside the liquid. The fabric covers the vent and is both waterproof and breathable, e.g., Gore-Tex®. The vent may be integrated into an electrical connector for the pressure sensor, and the electrical connector may provide IP-65 protection. The sensor may be particularly be employed in an aeroponic plant growth system where the fabric prevents mist from blocking the vent and/or vent tube.

Abstract: A plant holder for a hydroponic system includes a first structure shaped to hold a plant during an early growth stage and a second structure configured to hold the first structure during a later growth stage. The first structure is sized to directly fit in a tray having a high plant density. The second structure is sized to directly fit openings in a tray having a lower plant density. Plants in early stages of growth may be efficiently grown with the first structures in the high-plant-density tray, and the first structures with the plants may be easily transferred to more spacious trays without damaging the plants.

Abstract: An aeroponic plant-growth system includes growth space and a control unit that may be assembled using factory made modules. The growth space includes layers at different heights, and each layer includes plant holders and misters positioned to apply a mist to roots of plants in the plant holders. The control unit employs a controller to execute a program that operates a liquid supply system to provide liquid flows to the misters in the layers. Each of the liquid flows may be regulated according to the height of the layers.

Abstract: A gas separation cartridge including a housing comprising an inlet port for an air sample to enter; a top cover attached to the housing; an upper cavity comprising individual chambers comprised of a chemical or an absorbent or a mixture thereof attached to the top cover wherein each end of each chamber has an opening; a bottom cover attached to the upper cavity, wherein the bottom cover comprises a lower cavity, a separate opening for an air sample traveling from an individual chamber to pass through, and a separate opening for an air sample that does not pass through an individual chamber; and a base upon which the bottom cover of the cartridge is seated, wherein the base has an exit port.

Abstract: A hydroponic system includes a first sensor system that measures one or more characteristics of a nutrient solution, a second sensor system that measures one or more characteristics of an environment of a plant; and a network device including a communication interface to the first sensor system and a communication interface to the second sensor system. The network device may be configured to transmit measurements from the sensor systems through a wireless network to a remote device or database. The network device and the sensor systems may be implemented in a housing that fits within a collar of the hydroponic system. The collar can allow easy replacement of the sensor systems and can electrically isolate the sensor systems.

Abstract: A hydroponic system includes a first sensor system that measures one or more characteristics of a nutrient solution, a second sensor system that measures one or more characteristics of an environment of a plant; and a network device including a communication interface to the first sensor system and a communication interface to the second sensor system. The network device may be configured to transmit measurements from the sensor systems through a wireless network to a remote device or database. The network device and the sensor systems may be implemented in a housing that fits within a collar of the hydroponic system. The collar can allow easy replacement of the sensor systems and can electrically isolate the sensor systems.

Abstract: A hydroponic growth system may be integrated into a programmable system providing for the growth of plants. An upper section of a system may include a lighting system able to vary lighting characteristics such as the intensity or spectral content of light provided to the plants and atmospheric systems to control the temperature, flow, or humidity of air around the plants that are mounted on an actuated platform. A control system may execute a program to control the available systems including the actuated above-plant platform to programmably control the height or heights of the systems above plants.

Abstract: A gas separation cartridge including a housing comprising an inlet port for an air sample to enter; a top cover attached to the housing; an upper cavity comprising individual chambers comprised of a chemical or an absorbent or a mixture thereof attached to the top cover wherein each end of each chamber has an opening; a bottom cover attached to the upper cavity, wherein the bottom cover comprises a lower cavity, a separate opening for an air sample traveling from an individual chamber to pass through, and a separate opening for an air sample that does not pass through an individual chamber; and a base upon which the bottom cover of the cartridge is seated, wherein the base has an exit port.

Abstract: A photo-ionization detector having an adjustable drive power for a UV lamp implements a calibration operation that determines measurement signals for a series of drive power levels and based on the resulting measurement signals selects one or more drive power levels for normal operation of the PID. The calibration operation permits use of UV lamps having a wider range of performance levels and thereby improves manufacturing yields and extends the useful life of the PID. During normal operation, the PID further fine-tunes the drive power level to compensate for expected or measured degradation in lamp performance. Accordingly, between calibrations, the PID maintains a more uniform UV intensity for more accurate measurements. To expand the measurement range of the PID, the calibration process can select two or more power levels for use when measuring different gas concentrations.