Door position sensing

An exemplary method relates to determining an open/closed position of a door. The method generally involves generating, by a multi-axis magnetometer mounted to the door, a plurality of signals relating a magnetic field having a net magnetic flux point, and generating, by a controller and based on the plurality of signals, a current incidence angle defined between the multi-axis magnetometer and the net magnetic flux point. The method further includes comparing the current incidence angle to a known incidence angle, wherein the known incidence angle is defined between the multi-axis magnetometer and the net magnetic flux point when the door is in a known position. The method further includes determining the open/closed position of the door based on the comparison of the current incidence angle to the known incidence angle.

TECHNICAL FIELD

The present disclosure generally relates to door position sensors, and more particularly but not exclusively relates to such door position sensors for locksets.

BACKGROUND

Certain existing locksets utilize a magnetometer that senses the magnetic field of a magnet installed to the strike, and determine the open/closed state of the door based on information received from the magnetometer. More particularly, some locksets of this type determine the door position based on the three-dimensional position of a center of magnetic flux detected by the magnetometer. However, it has been found that such approaches may suffer from certain drawbacks, such as those relating to false-positive readings (i.e., indicating that the door is secured when the latchbolt has not been fully extended). For these reasons among others, there remains a need for further improvements in this technological field.

SUMMARY

An exemplary method relates to determining an open/closed position of a door. The method generally involves generating, by a multi-axis magnetometer mounted to the door, a plurality of signals relating a magnetic field having a net magnetic flux point, and generating, by a controller and based on the plurality of signals, a current incidence angle defined between the multi-axis magnetometer and the net magnetic flux point. The method further includes comparing the current incidence angle to a known incidence angle, wherein the known incidence angle is defined between the multi-axis magnetometer and the net magnetic flux point when the door is in a known position. The method further includes determining the open/closed position of the door based on the comparison of the current incidence angle to the known incidence angle. Further embodiments, forms, features, and aspects of the present application shall become apparent from the description and figures provided herewith.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

References in the specification to “one embodiment,” “an embodiment,” “an illustrative embodiment,” etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may or may not necessarily include that particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. It should further be appreciated that although reference to a “preferred” component or feature may indicate the desirability of a particular component or feature with respect to an embodiment, the disclosure is not so limiting with respect to other embodiments, which may omit such a component or feature. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to implement such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

Additionally, it should be appreciated that items included in a list in the form of “at least one of A, B, and C” can mean (A); (B); (C); (A and B); (B and C); (A and C); or (A, B, and C). Similarly, items listed in the form of “at least one of A, B, or C” can mean (A); (B); (C); (A and B); (B and C); (A and C); or (A, B, and C). Items listed in the form of “A, B, and/or C” can also mean (A); (B); (C); (A and B); (B and C); (A and C); or (A, B, and C). Further, with respect to the claims, the use of words and phrases such as “a,” “an,” “at least one,” and/or “at least one portion” should not be interpreted so as to be limiting to only one such element unless specifically stated to the contrary, and the use of phrases such as “at least a portion” and/or “a portion” should be interpreted as encompassing both embodiments including only a portion of such element and embodiments including the entirety of such element unless specifically stated to the contrary.

With reference toFIG. 1, illustrated therein is a closure assembly70according to certain embodiments. The closure assembly70generally includes a doorframe72, a door80movably mounted in the doorframe72, a strike assembly90mounted to the doorframe72, and an access control device mounted to the door80. In the illustrated form, the access control device is provided in the form of a lockset100according to certain embodiments. In other embodiments, the access control device may take another form, such as that of an exit device.

The strike assembly90includes a strike plate92that is mounted to the doorframe72and is aligned with a pocket73. The pocket73is operable to receive a latchbolt122of the lockset100when the door80is in a closed position. The strike assembly90further includes a magnetic field generator94operable to generate a magnetic field having a net magnetic flux point95. While other forms are contemplated, in the illustrated embodiment, the magnetic field generator94includes a pair of permanent magnets96mounted above and below the pocket73.

The lockset100generally includes a handleset110and a latch mechanism120operably connected with the handleset110. The handleset110includes an escutcheon112and a handle114rotatably mounted to the escutcheon112. The latch mechanism120includes a latchbolt122having an extended position and a retracted position, and is operably connected with the handleset110such that rotation of the handle114drives the latchbolt122from its extended position to its retracted position. The lockset100further comprises a multi-axis magnetometer130. The magnetometer130is operable to sense magnetic fields along at least two axes, and in the illustrated form is operable to sense magnetic fields along three mutually-orthogonal axes X, Y, and Z.

With additional reference toFIG. 2, the lockset100further includes a control assembly140in communication with the magnetometer130. The control assembly140includes a controller142and memory144having stored thereon instructions that, when executed by the controller142, cause the controller142to perform the operations or tasks described herein. The control assembly140may further include an energy storage device146and/or a wireless transceiver148that facilitates communication between the controller142and an external device190, such as an access control system192. As described herein, the controller142is configured to determine a condition of the door80based on information132received from the magnetometer130.

The magnetometer130is configured to generate information132corresponding to the strength of the sensed magnetic field, which corresponds to the relative position of the magnetometer130and the simulated net magnetic flux point95. The magnetometer130is a multi-axis magnetometer that generates such information132for each of at least two axes. In the illustrated form, the magnetometer130is a three-axis magnetometer that generates the information132for each of the three axes X, Y, and Z in the form of an X signal132x, a Y signal132y, and a Z signal132z. As described herein, in certain forms, the controller142may use only two of the three signals in determining the door condition, and the third signal may be ignored or disregarded. Thus, in certain forms, the magnetometer130may be provided as a two-axis magnetometer that generates the information for only two of the three axes X, Y, and Z. During operation, the value of each signal132x,132y,132zvaries based on the relative position of the magnetometer130and the net magnetic flux point95. As such, the relative position of the magnetometer130and the net magnetic flux point95can be determined based on the signals132x,132y,132zgenerated by the magnetometer130.

With additional reference toFIG. 3, illustrated therein is the closure assembly70in a secured condition, in which the door80is in its closed position and the latchbolt122is in its extended position and resting securely in the strike pocket73. In this condition, a vectorOPhomeextends between an origin point O defined by the magnetometer130and a home position Phome, which is a theoretical point in space defined based on the signals132x,132y,132zof the magnetometer130. Generally speaking, the home position Phomecorresponds to the position of the net magnetic flux point95relative to the magnetometer130. The home position Phomeincludes positional components Xhome, Yhome, Zhome, which respectively correspond to the signals132X,132Y,132Zgenerated by the magnetometer130. Based on the home position Phome, a home position incidence angle θhomecan be generated. The home position incidence angle θhomemay be defined as the projection of the vectorOPhomeonto a selected plane. In the illustrated form, the home position incidence angle θhomeis defined along the X-Y plane. As such, the home position incidence angle θhomecan be calculated based on Xhomeand Yhomeaccording to

During a calibration procedure, the lockset100may determine the home position Phomebased on plural sets of information132generated when the closure assembly70is in the secured condition. For example, if ten sets of information132were used to calibrate the home position Phome, the home position component Xhomemay be calculated according to

Xh⁢o⁢m⁢e=11⁢0⁢∑i=110⁢Xi,Equation⁢⁢2
where Xiis determined based on the X signal132Xfor each of ten iterations. The remaining home position parameters Yhomeand Zhomemay be calculated in an analogous manner, and the home position incidence angle θhomecan be calculated based on the determined home position parameters Xhomeand Yhome. As described herein, the home position incidence angle θhomeserves as a known incidence angle to which subsequently-calculated incidence angles are compared.

Following the calibration procedure, the lockset100may determine the condition of the closure assembly70based on information132received from the magnetometer130. As described herein, the lockset100utilizes a current set of information132to determine a current incidence angle θcurrent, compares the current incidence angle θcurrentto the home position incidence angle θhome, and determines the condition of the closure assembly70based at least in part upon the comparison of the current incidence angle θcurrentwith the home position incidence angle θhome.

With additional reference toFIG. 4, illustrated therein is the closure assembly70with the door80in an open position. As a result of the open position of the door80, the net magnetic flux point95has, relative to the magnetometer130, a current position Pcurrentdifferent from the home position Phome. The current position Pcurrentincludes components Xcurrent, Ycurrent, Zcurrent, and a vectorOPcurrentextends between the origin point O and the current position Pcurrent. As a result, the signals132X,132Y,132Zhave values corresponding to the components Xcurrent, Ycurrent, Zcurrentof the current position Pcurrent. In order to determine the current incidence angle θcurrent, the lockset100generates current position values Xcurrent, Ycurrent, Zcurrentbased on the current values of the signals132X,132Y,132Z. The current incidence angle θcurrentis then calculated in a manner analogous to that described above with reference to the calculation of the home position incidence angle θhome. More particularly, the current incidence angle θcurrentis calculated according to

θcurrent=tan-1⁡(Yc⁢u⁢r⁢r⁢e⁢n⁢tXc⁢u⁢r⁢r⁢e⁢n⁢t).Equation⁢⁢3
The home position incidence angle θhomeand the current incidence angle θcurrentmay be normalized to a selected region of the unit circle to compensate for different installations and orientations that may arise. The normalization may be provided according to Logic 1:

Those skilled in the art will readily appreciate that Logic 1 normalizes the incidence angles θ to a value between π/4 radians (i.e., 45°) and π/2 radians (i.e. 90°). However, it should be understood that the other ranges may be utilized for the normalization, and that Logic 1 may be revised as desired to provide for normalization to another range. After optionally normalizing the incidence angles, the home position incidence angle θhomeand the current incidence angle θcurrentmay be compared to determine a condition of the closure assembly70.

In certain embodiments, the home position incidence angle θhomemay be provided with an upper threshold and a lower threshold. For example, a lower threshold θlowermay be calculated according to Equation 4: θlower=θhome·(1−Th), where This a threshold multiplier. Similarly, an upper threshold θuppermay be calculated according to Equation 5: θupper=θhome·(1+Th), where This the threshold multiplier. The threshold multiplier This a function of the specific form of closure assembly70in which the lockset100is installed, and may vary based on several factors, including door width, door thickness, backset, and style of the access control device. The threshold multiplier Thmay be determined experimentally for a particular type of installation, and subsequently used in other installations of the same type.

After normalizing the incidence angles θhome, θcurrentand generating the thresholds θlower, θupper′the lockset100may determine the condition of the closure assembly70based on a comparison of the current incidence angle θcurrentwith the home position incidence angle θhome. For example, the lockset100may determine the current condition based on Logic 2:

if (θlower<θcurrent<θupper)→{Secured}

The secured state of the closure assembly70includes the closed position of the door80, and may further include the extended position of the latchbolt122in the strike pocket73. For example, the secured state may be a true door secured state in which the door80is closed and the latchbolt122is extended into the strike92, thereby securing the door80in the closed position. In certain embodiments, the secured condition may be a mock door secured state in which the door80is in a nearly-closed position such that the strike92prevents full extension of the latchbolt122. It has been found that the algorithm described hereinabove exhibits a sufficient sensitivity that it is possible to distinguish between the true door secured condition and the mock door secured condition. This is in contrast to certain prior approaches to using a magnetometer to determine door position, in which the algorithm lacks the sensitivity to distinguish between the true door secured condition and the mock door secured condition. As such, the current approach may be capable of determining the true door secured condition with a greater fidelity than such prior approaches.

In the embodiment described hereinabove, the incidence angles are calculated along the vertical X-Y plane that extends parallel to the vertical face of the door80. It is also contemplated that the incidence angles may be calculated along another plane, in which case the incidence angles would be calculated based on the pair of position signals corresponding to the plane. For example, in embodiments in which the incidence angles are defined along the X-Z plane, each incidence angle would be calculated based on the signals132xand132z. However, contrary to expectations, it has been found that the best results may occur when the vertical plane parallel to the face of the door80is used as the reference plane.

In certain forms, the lockset100may calculate plural home position incidence angles and plural current position incidence angles. For example, a first home position incidence angle Nome may be calculated along the X-Y plane, and a second home position incidence angle ϕhomemay be calculated along the X-Z plane, as illustrated inFIG. 4. In such forms, the lockset100may similarly calculate a first current position incidence angle θhomealong the X-Y plane and a second current position incidence angle ϕcurrentalong the X-Z plane. Those skilled in the art will readily recognize that the second home position incidence angle home and the second current position incidence angle ϕcurrentmay be calculated based on the signals132xand132zin a manner analogous to that in which the first incidence angles θhomeand θcurrentare calculated based on the signals132xand132y. The second incidence angles ϕhomeand ϕcurrentmay be normalized along the lines set forth in Logic 1, have thresholds generated along the lines set forth above in Equations 4 and 5, and be evaluated along the lines set forth in Logic 2. In certain forms, the lockset100may determine that the closure assembly70is in the secured condition when both the first and second current incidence angles θcurrentand ϕcurrentare within the range defined by the corresponding thresholds, and may determine that the closure assembly70is in the unsecured condition when either of the current incidence angles θcurrentand ϕcurrentfall outside the range defined by the corresponding thresholds.

With additional reference toFIG. 5, illustrated therein is an example process200that may, for example, be performed with or by the lockset100. Blocks illustrated for the processes in the present application are understood to be examples only, and blocks may be combined or divided, and added or removed, as well as re-ordered in whole or in part, unless explicitly stated to the contrary. Unless specified to the contrary, it is contemplated that certain blocks performed in the process200may be performed wholly by the lockset100(e.g., by the magnetometer130and/or the control assembly140) and/or the external device190, or that the blocks may be distributed among one or more of the elements and/or additional devices or systems that are not specifically illustrated inFIGS. 1-4. Furthermore, while the blocks are illustrated in a generally serial fashion, it is to be appreciated that two or more of the blocks may be performed concurrently during performance of the process200.

The process200generally includes a calibration procedure210and an operating procedure220. As described herein, the calibration procedure210generally involves calibrating an access control device such as the lockset100, and the operating procedure220generally involves operating the calibrated access control device (e.g., the lockset100) to determine a current condition of the closure assembly70. While the process200is described herein with specific reference to the lockset100, it is to be appreciated that the process200may be performed using another form of access control device that includes a magnetometer, such as an exit device having a magnetometer.

The calibration procedure210may include block212, which is performed while the closure assembly70is in a known condition. In the illustrated form, block212is performed while the closure assembly70is in the true door secured condition, in which the door80is fully closed and the latchbolt122is extended into the pocket73. Block212generally involves generating a plurality of home position signal sets using the magnetometer130. Block212may, for example, involve generating ten sets of information132, each including signals132x,132y,132zcorresponding to a respective iteration component Xi, Yi, Zi. The iteration components Xi, Yi, Zimay be averaged using Equation 1 above to determine the components Xhome, Yhome, and Zhome, thereby defining the home position Phomeof the net magnetic flux point95relative to the magnetometer130.

The calibration procedure210also includes block214, which generally involves generating the home position incidence angle θhomebased on the home position Phomecalculated in block212. In certain embodiments, block214involves generating the home position incidence angle θhomebased on the X and Y components Xhome, Yhomeaccording to Equation 2 above, and the Z component Zhomeis disregarded. In such forms, block212may not necessarily involve generating the Z signal132zfor the home position signal sets, or may omit the calculation of the Z component Zhome. In other embodiments, block214may involve generating the second home position incidence angle ϕhome. In such forms, block212would involve generating the Z signal132zand/or calculating the Z component Zhome.

The calibration procedure210may further include block216, which generally involves normalizing the home position incidence angle θhometo a selected segment of the unit circle. Block216may, for example, involve normalizing the home position incidence angle θhomeaccording to Logic 1 above. Block216may further involve normalizing the second home position incidence angle ϕhomealong analogous lines.

The calibration procedure210may further include block218, which generally involves generating thresholds based on the home position incidence angle θhome. The thresholds may be based on the normalized home position incidence angle θhome, for example in embodiments in which the calibration procedure210includes block216. Block218may, for example, involve generating a lower threshold θloweraccording to Equation 4 above and/or generating an upper threshold θupperaccording to Equation 5 above. Block218may further include generating second thresholds ϕupperand ϕlowerbased on the second home position incidence angle ϕhome.

The operating procedure220may begin with block222, which generally involves generating a current position signal set using the magnetometer130. Block222may, for example, involve generating signals132x,132y,132zand determining the components Xcurrent, Ycurrent, Zcurrentbased on the signals132x,132y,132z, thereby defining the current position Pcurrentof the net magnetic flux point95relative to the magnetometer130.

The operating procedure220also includes block224, which generally involves generating the current incidence angle θcurrentbased on the sensed current position Pcurrent. In certain embodiments, block224involves generating the current position incidence angle θcurrentbased on the X and Y components Xcurrent, Ycurrentaccording to Equation 3 above, and the Z component Zcurrentis disregarded. In such forms, block222may not necessarily involve generating the Z signal132zfor the current position signal set, or may omit the calculation of the Z component Zcurrent. In other embodiments, block224may involve generating the second current position incidence angle ϕcurrent. In such forms, block222may involve generating the Z component Zcurrentbased on the signal132z.

The operating procedure220may further include block226, which generally involves normalizing the current incidence angle θcurrentto the selected segment of the unit circle. Block226may involve normalizing the current incidence angle θcurrentbased on the normalization of the home position incidence angle θhomeaccording to Logic 1 above. Block226may further involve normalizing the second current incidence angle ϕcurrentalong analogous lines.

The operating procedure220further includes block228, which generally involves determining the current condition of the closure assembly70based on a comparison of the current incidence angle θcurrentand the home position incidence angle θhome. For example, block228may involve determining the current condition of the closure assembly70by comparing the current incidence angle θcurrentwith the upper and lower thresholds θupper, θloweraccording to Logic 2 above, thereby determining the secured/unsecured condition of the closure assembly70. In certain forms, the determination of block228may additionally or alternatively be based on the second current incidence angle ϕcurrent. For example, block228may involve determining the secured condition of the closure assembly70when both current incidence angles θcurrentand ϕcurrentare within the range defined by the corresponding thresholds, and may determine that the closure assembly70is in the unsecured condition when either of the current incidence angles θcurrentand ϕcurrentfall outside the range defined by the corresponding thresholds.

With the operating procedure220complete, the lockset100has determined the secured/unsecured condition of the closure assembly70. Information related to the determined condition may be stored in an audit trail (e.g., in memory144) and/or transmitted to the external device190(e.g., via the wireless transceiver148). The operating procedure220may be reiterated periodically, for example every three seconds, to aid in the generation of an audit trail. Additionally or alternatively, the operating procedure220may be reiterated in the event of an initializing condition, such as the detection of a credential being presented to the lockset100and/or a request from the external device190.

Referring now toFIG. 6, a simplified block diagram of at least one embodiment of a computing device300is shown. The illustrative computing device300depicts at least one embodiment of a lockset, control assembly, or controller that may be utilized in connection with the lockset100, the control assembly140, and/or the controller142illustrated inFIGS. 1-4.

Depending on the particular embodiment, the computing device300may be embodied as a server, desktop computer, laptop computer, tablet computer, notebook, netbook, Ultrabook™ mobile computing device, cellular phone, smartphone, wearable computing device, personal digital assistant, Internet of Things (IoT) device, reader device, access control device, control panel, processing system, router, gateway, and/or any other computing, processing, and/or communication device capable of performing the functions described herein.

The computing device300includes a processing device302that executes algorithms and/or processes data in accordance with operating logic308, an input/output device304that enables communication between the computing device300and one or more external devices310, and memory306which stores, for example, data received from the external device310via the input/output device304.

The input/output device304allows the computing device300to communicate with the external device310. For example, the input/output device304may include a transceiver, a network adapter, a network card, an interface, one or more communication ports (e.g., a USB port, serial port, parallel port, an analog port, a digital port, VGA, DVI, HDMI, FireWire, CAT 5, or any other type of communication port or interface), and/or other communication circuitry. Communication circuitry may be configured to use any one or more communication technologies (e.g., wireless or wired communications) and associated protocols (e.g., Ethernet, Bluetooth®, Bluetooth Low Energy (BLE), WiMAX, etc.) to effect such communication depending on the particular computing device300. The input/output device304may include hardware, software, and/or firmware suitable for performing the techniques described herein.

The external device310may be any type of device that allows data to be inputted or outputted from the computing device300. For example, in various embodiments, the external device310may be embodied as the lockset100, the magnetometer130, the control assembly140, and/or the external device190. Further, in some embodiments, the external device310may be embodied as another computing device, switch, diagnostic tool, controller, printer, display, alarm, peripheral device (e.g., keyboard, mouse, touch screen display, etc.), and/or any other computing, processing, and/or communication device capable of performing the functions described herein. Furthermore, in some embodiments, it should be appreciated that the external device310may be integrated into the computing device300.

The processing device302may be embodied as any type of processor(s) capable of performing the functions described herein. In particular, the processing device302may be embodied as one or more single or multi-core processors, microcontrollers, or other processor or processing/controlling circuits. For example, in some embodiments, the processing device302may include or be embodied as an arithmetic logic unit (ALU), central processing unit (CPU), digital signal processor (DSP), and/or another suitable processor(s). The processing device302may be a programmable type, a dedicated hardwired state machine, or a combination thereof. Processing devices302with multiple processing units may utilize distributed, pipelined, and/or parallel processing in various embodiments. Further, the processing device302may be dedicated to performance of just the operations described herein, or may be utilized in one or more additional applications. In the illustrative embodiment, the processing device302is of a programmable variety that executes algorithms and/or processes data in accordance with operating logic308as defined by programming instructions (such as software or firmware) stored in memory306. Additionally or alternatively, the operating logic308for processing device302may be at least partially defined by hardwired logic or other hardware. Further, the processing device302may include one or more components of any type suitable to process the signals received from input/output device304or from other components or devices and to provide desired output signals. Such components may include digital circuitry, analog circuitry, or a combination thereof.

The memory306may be of one or more types of non-transitory computer-readable media, such as a solid-state memory, electromagnetic memory, optical memory, or a combination thereof. Furthermore, the memory306may be volatile and/or nonvolatile and, in some embodiments, some or all of the memory306may be of a portable variety, such as a disk, tape, memory stick, cartridge, and/or other suitable portable memory. In operation, the memory306may store various data and software used during operation of the computing device300such as operating systems, applications, programs, libraries, and drivers. It should be appreciated that the memory306may store data that is manipulated by the operating logic308of processing device302, such as, for example, data representative of signals received from and/or sent to the input/output device304in addition to or in lieu of storing programming instructions defining operating logic308. As illustrated, the memory306may be included with the processing device302and/or coupled to the processing device302depending on the particular embodiment. For example, in some embodiments, the processing device302, the memory306, and/or other components of the computing device300may form a portion of a system-on-a-chip (SoC) and be incorporated on a single integrated circuit chip.

In some embodiments, various components of the computing device300(e.g., the processing device302and the memory306) may be communicatively coupled via an input/output subsystem, which may be embodied as circuitry and/or components to facilitate input/output operations with the processing device302, the memory306, and other components of the computing device300. For example, the input/output subsystem may be embodied as, or otherwise include, memory controller hubs, input/output control hubs, firmware devices, communication links (i.e., point-to-point links, bus links, wires, cables, light guides, printed circuit board traces, etc.) and/or other components and subsystems to facilitate the input/output operations.

The computing device300may include other or additional components, such as those commonly found in a typical computing device (e.g., various input/output devices and/or other components), in other embodiments. It should be further appreciated that one or more of the components of the computing device300described herein may be distributed across multiple computing devices. In other words, the techniques described herein may be employed by a computing system that includes one or more computing devices. Additionally, although only a single processing device302, I/O device304, and memory306are illustratively shown inFIG. 6, it should be appreciated that a particular computing device300may include multiple processing devices302, I/O devices304, and/or memories306in other embodiments. Further, in some embodiments, more than one external device310may be in communication with the computing device300.