Abstract: A system for an unmanned aerial vehicle can include an altitude control system 320, which further includes a compressor assembly 400, a valve assembly 500, and an electronics control assembly 600. The compressor assembly may include a compressor housing 410 that includes a compressor inlet 402, an outlet 202, and a cavity 414 extending therethrough and joining the inlet to the outlet. A diffuser 408 may be coupled to the compressor housing. A motor housing 407 may be disposed within the central cavity at the inlet of the compressor housing, and a compressor motor 406 may be disposed within the motor housing. An impeller 412 disposed within the compressor housing may be coupled to a driveshaft 444 for rotation therewith. The valve assembly may be coupled to an opening 416 of the compressor inlet. The valve head 502 may be configured to move into and away from the inlet opening so as to change a size of the circumferential area of the inlet opening.

Abstract: A bracket for a floating shelf comprises a solid plate with a planar back side to abut to a wall. A plurality of circular apertures extends through the solid plate and have internal screw threads. A plurality of rods is secured to the solid plate and extending therefrom, with each rod having a proximal end received within a different one of the plurality of circular apertures. The plurality of rods has external screw threads on the proximal end mating with a respective internal screw thread of respective circular apertures. The proximal ends of the plurality of rods are flush with the planar back side of the solid plate and the wail.

Abstract: A system for an unmanned aerial vehicle can include an altitude control system, which further includes a compressor assembly, a valve assembly, and an electronics assembly. The compressor assembly may include a driveshaft and a bearing assembly configured to rotate the driveshaft. The driveshaft may be formed from a first material and a compressor housing may be formed from a second material. The first and second materials may have different rates of thermal expansion. A dynamic preloading mechanism, such as a flexible plate, may be provided within the compressor assembly to exert a preloading force on the bearing assembly. Throughout the duration of the flight of the unmanned aerial vehicle, the preloading mechanism can continually compensate for differences in rates of thermal expansion between the first and second materials throughout.

Abstract: The present disclosure provides an engineered wood precursor mixture. The mixture includes a wood substrate(s) and a binder reaction mixture present in a range of from 3 to 25 parts per one hundred (100) parts of the dry weight of the wood substrate. The binder composition includes an aqueous portion. The aqueous portion includes a carbohydrate-containing component, including glucose, fructose, sucrose, or mixture thereof, in a range of from 2 wt % to 85 wt % based on a dry weight of the binder reaction mixture. The aqueous portion further includes 1 wt % to 33 wt % of a base based on a dry weight of the binder reaction mixture, wherein a pH of the aqueous portion is greater than 10. The binder composition further includes a partially non-dissolved polypeptide-containing component, in a range of from 20 wt % to 85 wt % based on the dry weight of the binder reaction mixture.

Abstract: Combustion heater control systems and methods that include dynamic safety settings. Current operating parameters of the combustion heater are sensed at a plurality of time intervals and converted into a time-varying signal. The time-varying signal is compared to a burner stability envelope indicating when a burner is likely to enter an unstable state. The unstable state may include huffing, flashback, and/or liftoff. When the burner is likely to enter an unstable state, the combustion heater is controlled to prevent the unstable state.

Abstract: A door system includes a door jamb, a door panel, a window disposed in the door panel, a plurality of electronic components, a hinge pivotally coupling an edge of the door panel to the door jamb, and a control system disposed within the door panel. The plurality of electronic components include an electronic locking mechanism coupled to the door panel, a camera coupled to the door panel, a sensor configured to facilitate detecting at least one of sound or activity proximate the door panel, and a backup battery disposed in at least one of the door jamb or the door panel. The edge of the door panel is configured to receive power from an external power source to power the plurality of electronic components. The backup battery is configured to power at least one of the plurality of electronic components in an event of power loss from the external power source.

Abstract: An altitude control system for an unmanned aerial vehicle includes a compressor assembly defining a plenum therein, a passive valve assembly coupled to a first portion of the compressor assembly and in fluid communication with the plenum, and an active valve assembly coupled to a second portion of the compressor assembly and in fluid communication with the plenum. A method of controlling an altitude of an unmanned aerial vehicle and an unmanned aerial vehicle are also provided.

Abstract: Systems and methods for determining operating discrepancy a process heater. The discrepancy may be identified by solving a fired-systems model of the heater. The fired-systems model is then compared to current operating data. If the sensed current operating data is outside of the expected value(s), as defined by the fired-systems model, the systems and methods may take a remediation action to resolve the discrepancy. The discrepancy may include convection fouling identification and identification of tramp-air leaks within the process heater that are otherwise not easily detected by a human operator.

Abstract: The technology relates to techniques for an aquatic energy discharge system for an energy storage system of an aircraft. An aquatic energy discharge system can include an energy storage system, a pair of electrodes coupled to the energy storage system, and a water detection system configured to detect a water landing. The electrodes can be configured to submerge in a body of water after the aircraft has landed in the body of water, and cause a hydrolysis reaction that drains energy from the energy storage system in response to the water detection system detecting the water landing. A method of discharging an energy storage system of an aircraft can include detecting that an aircraft (or portion thereof) has landed in a body of water, and discharging the energy storage system by powering a hydrolysis reaction using a pair of electrodes.

Abstract: A lock system includes a processing circuit. The processing circuit is configured to store an access credential for a locking device. The access credential is associated with a user. The access credential has a lifespan. The processing circuit is further configured to deliver the access credential to a user device associated with the user to facilitate accessing the locking device with the user device, monitor a frequency at which the user device accesses the locking device using the access credential, and adjust the lifespan of the access credential based on the frequency.

Abstract: A locking system includes a server, an electronic locking mechanism, and a controller associated with a user. The controller is configured to detect the electronic locking mechanism and acquire lock data therefrom, and transmit the lock data to the server. The server, absent any interaction from the user, is configured to receive the lock data for the electronic locking mechanism, register the electronic locking mechanism to the user, and transmit an access credential for accessing the electronic locking mechanism to a user device associated with the user. The electronic locking mechanism is configured to receive the access credential directly from the user device or indirectly from the user device through the controller and make an access decision based on the access credential, independent of the server.

Abstract: The technology relates to a scalable power system. A scalable power system includes battery modules connected in parallel, a network of diodes, a battery management system that may be localized or centralized, a localized battery management system configured to control an individual battery module, a centralized battery management system configured to control all of the battery modules in the scalable power system. In a system with localized battery control, a parallelizing circuit board may connect battery modules to a system bus in parallel. The battery modules can be charged and discharged by the system bus. A method of adding a battery module to a scalable power system includes discharging a highest-charged battery module, then discharging a next highest-charged battery module until there are no remaining charged battery modules, then adding an additional battery module in parallel, and charging the connected battery modules in parallel.

Abstract: A lock system includes a plurality of electronic locking devices and a server. The server is configured to receive lock location data regarding a location of each of the plurality of electronic locking devices, receive user device location data regarding a current location of each of a plurality of user devices, deliver access credentials to each of the plurality of user devices according to a geofence delivery protocol based on the lock location data and the user device location data, monitor a current aggregate loading in response to using the geofence delivery protocol, and deliver access credentials to one or more of the plurality of user devices according to a non-geofence delivery protocol in response to the current aggregate loading exceeding a load threshold to reduce the current aggregate loading.

Abstract: A valve assembly for use with an unmanned aerial vehicle is provided and includes an inlet tube, a shuttle, a base plate, a screw assembly, and a spacer block. The shuttle is partially disposed within the inlet tube and is configured to be placed in a first position where the shuttle abuts the inlet tube and a second position where the outer surface is disposed in spaced relation to the inlet tube. The base plate extends between a first end portion that defines a cavity therein and a second end portion. The screw assembly is disposed within the cavity of the base plate and is coupled to a portion of the shuttle. The spacer block is interposed between the second end portion of the inlet tube and the first end portion of the base plate and is configured to maintain the inlet tube and the base plate in spaced relation.

Abstract: An additive manufacturing system comprises a build plane and an energy source configured to direct energy onto a work region of the build plane. An optical detector is configured to receive one or more optical signals from the work region. An optical filter is positioned between the work region and the optical detector, wherein the optical filter includes a first partially transmissive polarized filter having a first polarization axis and a second partially transmissive polarized filter having a second polarization axis. The first polarization axis is rotationally offset from the second polarization axis approximately 90 degrees. The optical filter improves the signal to noise ratio of the optical sensors.