A variable aperture orifice plate assembly for controlling and/or measuring fluid flow therethrough, from an upstream end to a downstream end. The orifice plate assembly includes a damper assembly having an array of adjustable cross-section apertures having an aggregate aperture area, upstream and downstream pressure sensors on opposite sides of the damper assembly, an actuator assembly for adjustably controlling the aggregate area of the apertures, and a processor configured for feedback operation in a closed-loop, to effect operation as an orifice plate. The processor is responsive to differential pressure across the damper assembly, and the aggregate area of the respective apertures normal to the flow paths of fluid flowing therethrough, to control the differential pressure and/or the aggregate area in a closed-loop manner so that fluid flowing between the array of apertures and the downstream end, is characterized by a corresponding array of vena contractae.

An air distribution apparatus that serves as a single sensing device for both lighting, LiFi, and HVAC functions that are operable on a single platform by building automation systems. The building automation system may be controllable by a single software system or network accessible locally on site or remotely off site. The air distribution apparatus can operate in a single zone or coupled with multiple like apparatuses for multi-zone operation. It is a high turndown, self-balancing system which allows for continuous commissioning with built-in fault diagnostic systems and that may be used as a supply, return, or exhaust system, or a combination thereof. The air distribution apparatus includes multi-stage airflow control systems that operate progressively based on unique actuation mechanisms and/or algorithms that allow for precise flow control and feedback to self-balance and commission the system.

According to one aspect, a control system for providing stable balance control may include an H.sup. controller, a state-feedback circuit, a first feedback loop, and a second feedback loop. The control system may be implemented in a robot as a controller for the robot. The H.sup. controller may receive an input signal and generate a control effort signal. The state-feedback circuit may receive the control effort signal as an input and generate an output signal. The feedback loop may include the H.sup. controller and the state-feedback circuit and may transfer the output signal of the state-feedback circuit back to the input of the H.sup. controller and input a tracking error input signal to the H.sup. controller. The tracking error input signal may be the difference between the output signal of the state-feedback circuit and the input signal.

An air distribution apparatus that serves as a single sensing device for both lighting, LiFi, and HVAC functions that are operable on a single platform by building automation systems. The building automation system may be controllable by a single software system or network accessible locally on site or remotely off site. The air distribution apparatus can operate in a single zone or coupled with multiple like apparatuses for multi-zone operation. It is a high turndown, self-balancing system which allows for continuous commissioning with built-in fault diagnostic systems and that may be used as a supply, return, or exhaust system, or a combination thereof. The air distribution apparatus includes multi-stage airflow control systems that operate progressively based on unique actuation mechanisms and/or algorithms that allow for precise flow control and feedback to self-balance and commission the system.

A fluid flow device that can measure and control a flow of a fluid is described. Various procedures, including measuring, controlling, balancing, or calibration procedures can leverage differential pressure measurement. These differential pressure measurements can be measured across the fluid flow device such that a first pressure measurement is taken upstream of the fluid flow device while a second pressure measurement is taken downstream of the fluid flow device. Moreover, one or more of the various pressure measurements, and in particular the downstream pressure measurement, can be performed at stagnation zone where the flow has stagnated. Such can provide significant amplification and/or turndown capabilities.

Systems and methods for measuring and controlling fluid flow include an orifice plate defining a variable opening. The orifice plate includes an outer assembly comprising a central opening and an inner assembly extending through the central opening. The flow device regulates high and very low volumes of fluid with precision, inexpensively, with superior acoustics, reduced energy, and simpler design. The high turndown device permits use at lower velocities, thereby reducing noise generation and eliminating need for sound-attenuating liners. The high rangeability device combines several part numbers into fewer parts, thereby streamlining product portfolios. In some cases, cost benefits associated with the flow device allow equipment to be scaled back 100:1 rather than 10:1, providing energy savings, fewer product variations, simple and more robust applications. The device meets new and old building fresh air, comfort and energy codes. The flow device can be engineered, selected, and sized without sophisticated software programs.

A fluid flow assembly for disposition along a fluid flow axis within an inward-facing surface extending between upstream and downstream ends. At least two damper blades extend from associated blade axes transverse to the flow axis. The damper blades include perimeter sections opposite the respective blade axes which are matching-in-shape to sections of the inward-facing surface. The damper blades are selectively driven by actuators to independently pivot about the respective blade axes between a closed position blocking fluid flow from the upstream end to the downstream end, to an open position angularly displaced therefrom. In a form, at least two damper blades have different cross-section areas between their respective blade axes and matching-in-shape perimeter sections. In a form, at least one damper blade is configured as an orifice plate.

A variable aperture orifice plate assembly for controlling and/or measuring fluid flow therethrough, from an upstream end to a downstream end. The orifice plate assembly includes a damper assembly having an array of adjustable cross-section apertures having an aggregate aperture area, upstream and downstream pressure sensors on opposite sides of the damper assembly, an actuator assembly for adjustably controlling the aggregate area of the apertures, and a processor configured for feedback operation in a closed-loop, to effect operation as an orifice plate. The processor is responsive to differential pressure across the damper assembly, and the aggregate area of the respective apertures normal to the flow paths of fluid flowing therethrough, to control the differential pressure and/or the aggregate area in a closed-loop manner so that fluid flowing between the array of apertures and the downstream end, is characterized by a corresponding array of vena contractae.

A self-balancing system that can obtain accurate flow measurements that can be used to perform the self-balancing in situ and during operation to satisfy a set point and without k factors or the use of TAB balancers. The building automation system may be controllable by a single software system or network accessible locally on site or remotely off site. The air distribution apparatus can operate in a single zone or coupled with multiple like apparatuses for multi-zone operation. It is a high turndown, self-balancing system which allows for continuous commissioning with built-in fault diagnostic systems and that may be used as a supply, return, or exhaust system, or a combination thereof. The air distribution apparatus can include multi-stage airflow control systems that operate progressively based on unique actuation mechanisms and/or algorithms that allow for precise flow control and feedback to self-balance and commission the system.

An air distribution apparatus that serves as a single sensing device for lighting, LiFi, and HVAC functions that are operable on a single platform by building automation systems. The building automation system may be controllable by a single software system or network accessible locally on site or remotely off site. The air distribution apparatus can operate in a single zone or coupled with multiple like apparatuses for multi-zone operation. It is a high turndown, self-balancing system which allows for continuous commissioning with built-in fault diagnostic systems and that may be used as a supply, return, or exhaust system, or a combination thereof. The air distribution apparatus includes multi-stage airflow control systems that operate progressively based on unique actuation mechanisms and/or algorithms that allow for precise flow control and feedback to self-balance and commission the system.