Patent Publication Number: US-7719213-B2

Title: Door actuator and opener

Description:
FIELD OF THE INVENTION 
     The present invention relates in general to automated mechanical systems and, more particularly, to an apparatus, system and method of remotely actuating a door. 
     BACKGROUND OF THE INVENTION 
     A certain percentage of every community includes individuals who have physical disabilities or are otherwise unable to perform many common and ordinarily routine physical tasks, such as opening a door. Implementation of the Americans with Disabilities Act (ADA) has resulted in greater access that individuals with physical disabilities have to the greater community at large. For example, the Act requires that accessible doors include a large push-button switch which a disabled person can press to actuate a door opener and open the door. The switch is usually located in close proximity to the door opening. 
     In many cases, however, certain individuals have difficulty physically reaching or depressing the switch to actuate the door. Some persons have disabilities associated with bodily extremities, for example, the inability to move arms or hands. The disabled persons who cannot depress the switch cannot gain access to a building without additional assistance. 
     A wide variety of remote door opening systems can be found in the art which use wireless and/or infrared communications schemes. Companies offer, for example, wireless door opening systems that use a remote control to open a door. However, the remote controls require a disabled user to depress a button (on the remote) each time the user approaches a door, which is again difficult for many persons with disabilities. In addition, the remote controls must be programmed by the user in order for the remotes to function with each door opening motor. The prospect of programming remote controls can be intimidating, inconvenient, and time consuming to a disabled user. 
     A particular remote opening system having a push-button remote control is marketed which is preprogrammed compatible with every door which includes a proprietary fixed receiving unit. However, the remote opening system still requires a user to depress a button or otherwise physically exerts a user to perform the door actuating and opening function. 
     Finally, alternative technologies that are not specifically designed for use by people with disabilities, but rather can be activated by any user, such as infrared or microwave technologies, do not solve the problem. The technologies lack compatibility with many doors, and are typically only used on sliding doors such as those seen at airports and grocery stores. In addition, systems exhibiting the infrared or microwave technologies must be mounted in very specific locations around a door, which limits the system&#39;s ability to be installed on some doors. 
     Thus, a need exists for an apparatus, system, and method which serve to perform a door actuating and opening function without requiring physical exertion on the part of a user. In addition, a need exists for such an apparatus and system to be cost-efficient and effective, to encourage the implementation of the systems in as many applications and settings as possible to promote universal accessibility to people with disabilities and other users who can use assistance. 
     SUMMARY OF THE INVENTION 
     In one embodiment, the present invention is an actuating mechanism for a door comprising a first antenna block having a first integrated microcontroller electrically connected to a first transceiver device and a first antenna, a second antenna block having a second integrated microcontroller electrically connected to a second transceiver device and a second antenna, and a processor device electrically connected between the first and second microcontrollers and a first switch, the first switch configured to be coupled in parallel with a second switch, wherein the first and second antennas receive a first radio frequency signal from a third mobile transceiver device, the first and second microcontrollers process the first radio frequency signal and send a control signal to the processor device, and the processor device calculates a time difference of arrival (TDOA) of the first radio frequency signal, then computes a direction of arrival (DOA) utilizing the TDOA measurement, the DOA measurement compared against a predefined range of DOAs, whereupon the processor device sends a control signal to the first switch to actuate the door in the event of a match. 
     In another embodiment, the present invention is a door actuating system comprising a first mobile transceiver electrically coupled to a first microcontroller and a first antenna, a second transceiver electrically coupled to a second antenna, a third transceiver electrically coupled to a third antenna, and a processing device electrically coupled between the second and third antennas and a first switch, the first switch configured to be coupled in parallel with a second switch, wherein the first mobile transceiver receives a first radio frequency signal from the second or third transceivers, the signal detected by the first microcontroller, the first microcontroller instructs the first mobile transceiver to send a second radio frequency signal which is received by the second and third transceivers, and the processing device calculates a time difference of arrival (TDOA) of the second radio frequency signal, then computes a direction of arrival (DOA) utilizing the TDOA measurement, the DOA measurement compared against a predefined range of DOAs, whereupon the processor device sends a control signal to the first switch to actuate the door in the event of a match. 
     In yet another embodiment, the present invention is a method of actuating a door, comprising receiving a first radio frequency signal by a first mobile transceiver device detecting the receipt of the first radio frequency signal by a first microcontroller connected to the first mobile transceiver device, instructing the first mobile transceiver to transmit a second radio frequency signal, receiving the second radio frequency signal by a second and a third transceiver device, calculating a time difference of arrival (TDOA) of the second radio frequency signal by a processing device connected to the second and third transceiver devices, calculating a direction of arrival (DOA) using the TDOA measurement by the processing device, comparing the DOA against a predefined range of DOAs by the processing device, and sending a control signal by the processing device to a first switch to actuate the door in the event of a DOA match. 
     In still another embodiment, the present invention is a method of manufacturing an actuating mechanism for a door, comprising providing a first antenna block having a first integrated microcontroller electrically connected to a first transceiver device and a first antenna, providing a second antenna block having a second integrated microcontroller electrically connected to a second transceiver device and a second antenna, and providing a processor device electrically connected between the first and second microcontrollers and a first switch, the first switch configured to be coupled in parallel with a second switch, wherein the first and second antennas receive a first radio frequency signal from a third mobile transceiver device, the first and second microcontrollers process the first radio frequency signal, and send a control signal to the processor device, and the processor device computes a time difference of arrival (TDOA) of the first radio frequency signal, then computes a direction of arrival (DOA) utilizing the TDOA measurement, the DOA measurement compared against a predefined range of DOAs, whereupon the processor device sends a control signal to the first switch to actuate the door in the event of a match. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1   a  and  1   b  illustrate an example door actuating and opening apparatus and system during operation; 
         FIG. 2  illustrates a block diagram of an example mobile unit; 
         FIG. 3   a  illustrates a block diagram of an example fixed unit; 
         FIG. 3   b  illustrates a block diagram of an example fixed unit in a separate embodiment; 
         FIG. 4   a  illustrates a diagram of an example user approach angle; 
         FIG. 4   b  illustrates a close-up view of a fixed unit receiving radio frequency signals to determine a user approach angle; and 
         FIG. 5  illustrates a logical flow-chart diagram of an example operation of the door actuating and opening system; and 
         FIG. 6  illustrates an example operation of the door actuating and opening system in a flow-chart diagram. 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     The present invention is described in one or more embodiments in the following description with reference to the Figures, in which like numerals represent the same or similar elements. While the invention is described in terms of the best mode for achieving the invention&#39;s objectives, it will be appreciated by those skilled in the art that it is intended to cover alternatives, modifications, and equivalents as may be included within the spirit and scope of the invention as defined by the appended claims and their equivalents as supported by the following disclosure and drawings. 
     Some of the functional units described in this specification have been labeled as modules in order to more particularly emphasize their implementation independence. For example, a module may be implemented as a hardware circuit comprising custom VLSI circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A module may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices, or the like. 
     Modules may also be implemented in software for execution by various types of processors. An identified module of executable code may, for instance, comprise one or more physical or logical blocks of computer instructions which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module. 
     Indeed, a module of executable code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within modules, and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network. 
     Reference throughout this specification to “one embodiment,” “an embodiment,” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment,” “in an embodiment,” and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment. 
     Reference to a signal bearing medium may take any form capable of generating a signal, causing a signal to be generated, or causing execution of a program of machine-readable instructions on a digital processing apparatus. A signal bearing medium may be embodied by a transmission line, a compact disk, digital-video disk, a magnetic tape, a Bernoulli drive, a magnetic disk, punch card, flash memory, integrated circuits, or other digital processing apparatus memory device. 
     The schematic flow chart diagrams included are generally set forth as logical flow chart diagrams. As such, the depicted order and labeled steps are indicative of one embodiment of the presented method. Other steps and methods may be conceived that are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the illustrated method. Additionally, the format and symbols employed are provided to explain the logical steps of the method and are understood not to limit the scope of the method. Although various arrow types and line types may be employed in the flow chart diagrams, they are understood not to limit the scope of the corresponding method. Indeed, some arrows or other connectors may be used to indicate only the logical flow of the method. For instance, an arrow may indicate a waiting or monitoring period of unspecified duration between enumerated steps of the depicted method. Additionally, the order in which a particular method occurs may or may not strictly adhere to the order of the corresponding steps shown. 
     Furthermore, the described features, structures, or characteristics of the invention may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided, such as examples of programming, software modules, user selections, network transactions, database queries, database structures, hardware modules, hardware circuits, hardware chips, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention may be practiced without one or more of the specific details, or with other methods, components, materials, and so forth. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention. 
     A compact, wireless system can be utilized to actuate and open doors for persons with disabilities and/or those who otherwise have difficulty opening doors. The system includes a fixed mechanism or unit and a mobile unit, the units working together to actuate a door.  FIG. 1   a  illustrates the wireless system  10  in an example operation. A person  12  with a disability approaches a door  14 . A mobile unit  16  emits radio frequency signals  18  when the mobile unit  16  is within range of a door  14  equipped with a fixed unit  20 . The mobile unit  16  is configured to only activate when the unit  16  is within a specified range of the door  14  to be opened and fixed unit  20 . The mobile unit  16  receives signals  22  which are sent by fixed unit  20 . 
     The fixed unit  20  receives a second signal  18  that is sent from the mobile unit  16 , once the mobile unit  16  has received a first signal. The second signal  18  sent by mobile unit  16  can include a code which is verified by the fixed unit  20  to determine if the door  14  should be opened. As shown in  FIG. 1   b , the mobile unit  16  can be attached to a wheelchair or other device which provides accessibility to a user. In addition, mobile unit  16  can also be connected to a keychain, necklace, or other item which can be carried by a user. When the person  12  in the wheelchair becomes in close enough proximity to door  14  and fixed unit  20 , the mobile unit  16  receives first radio frequency signal  22  from fixed unit  20 . In response, the mobile unit  16  sends a second radio frequency signal  18  to instruct the fixed unit  20  to open the door. The Fixed unit  20  sends a control signal to an automatic door opening motor, and the door opens  24 . The entire process, as depicted, is completely wireless. No physical exertion is required on the part of the user  12  to activate the system  10 . 
     Turning to  FIG. 2 , a block diagram of a mobile unit module  16  subsystem is depicted. Mobile unit  16  includes a first antenna block  28 . The antenna block includes a microcontroller  34 , a transceiver device  36 , and an antenna  38 , each electrically connected with various signal bearing mediums as shown. A battery  30 , connected to ground  32 , is also coupled to block  28  to provide a remotely accessible source of power to the block  28 . In one embodiment, microcontroller  34  can be programmed to continually receive radio frequency signals in a power-conservation mode. Microcontroller  34  can sift through the various signals to detect and identify a proprietary and/or unique radio frequency signal  22  emanating from a particular fixed unit  20 . After the signal  22  is detected and identified, the mobile unit module  16  can transmit a second radio frequency signal  18  back to fixed unit  20 . 
       FIG. 3   a  shows a fixed unit module  20  which is configured to receive signals from above a door  14 . In the embodiment shown, two antenna block modules  28 , each having an integrated microcontroller  34 , transceiver device  36  and antenna  38 , are connected to a main microcontroller  42  or similar processor/processing device  42 . Device  42  is then coupled to a new switch  44 . Switch  44  actuates and/or supplies electrical power to door motor  46  which serves to actuate and open the door  14 . 
     As one skilled in the art would appreciate, microcontrollers  34  can be incorporated into main microcontroller or processing device  42 , such that a single processing device  42  performs the functionality described herein of receiving radio frequency signals, performing measurements and effecting calculations on the measurements. As such, a single processing device  42  can be directly connected to first and second transceivers  36  and antennas  38  as shown in  FIG. 3   b . In addition, the various electrical connections which connect the switch device  44  to door motor  46  can be low voltage in nature. A control signal can be supplied via switch device  44  to door motor  46 , which can have a separate, higher voltage connection to power supply  52 . In effect, switch  44  can act as a relay device  44  to turn on motor  46 . 
     Fixed unit  20  is intended to operate alongside existing disabled-accessible equipment. As such, new switch  44  is coupled in parallel with existing switch  48 , so that either switch  44  or switch  48  can independently operate to actuate and/or supply power to door motor  46 , actuate and open door  14 . Existing switch  48  can be integrated into such disabled-accessible devices as motion detectors, photoelectric devices, a floor mat which senses pressure to activate switch  48 , or even a manual switch  48 , such as the large pushbutton switches  48  which are commonly seen outside disabled-accessible restrooms and the like. Because switch  48  independently controls the operation of door motor  46  from switch  44 , system  10  can effectively function without negatively impacting the manual operation of existing switch  48  for disabled persons. 
     Components such as antenna block modules  28  and processor device  42  are powered by an AC/DC converting block  50 , which receives AC power from the same AC power supply  52  that the existing door opening switch  48  and motor  46  uses. Block  50  can include various switching power supplies which are known in the art and selected for a particular application. 
     Each antenna block module  28  can be mounted a specified distance away from the other antenna block module  28 , depending on a particular application or embodiment. The antenna modules  28  are programmed to send a signal to device  42  when the antenna module  28  receives a wireless radio frequency signal from a mobile unit module  16 . The device  42  then processes the signals the device  42  receives from each antenna block  28 , and determines an angle of approach of the mobile unit module  16 . The determination of the angle of approach will be further described. 
     Based upon the direction of approach, the device  42  makes a determination whether conditions are safe for door  14  to be opened. The determination will also be further described. If the mobile unit  16  is approaching the door  14  from an angle within a predetermined or specified range, the device  42  activates the switch  44  sending electrical power to door motor  46  to open the door  14 . In another embodiment, the device  42  sends a signal over a signal bearing medium to a receiving device attached to door motor  46  to actuate and open the door. 
     To detect the approach of a mobile unit module  16  from either side of a door  14 , the fixed unit configuration shown in  FIG. 3   a  can be modified by the addition of two additional antenna block modules  28  which are positioned on either side of the door  14 . The additional antenna modules  28  can have the similar electrical connections to both the AC/DC conversion block  50  and the main microcontroller processor device  42 . 
     Turning to  FIGS. 4   a  and  4   b , an illustration of method of calculating a user approach angle, or direction of arrival (DOA) is shown. Fixed unit  20  is shown mounted above a door  14  opening. A footprint of door  14  as the door  14  opens is shown by dotted line. A user  12  with an accompanying mobile unit module  16  is shown in close enough proximity to door  14  and fixed unit  20  to receive radio frequency signals  40  at each antenna block module  28 . FIG.  4   b  shows a close-up view of area  54  of  FIG. 4   a . Here, the individual antennas  38  (first and second) are seen, each receiving radio frequency signal  40 . 
     Radio frequency signal  40  is sent by a mobile unit module  16  at a fixed time. However, signals  40  arrive at the first and second antennas  38  at slightly different times. The fixed unit module  20  determines the angle that a user  12  is approaching a door  14  by measuring the time delay between when each fixed unit antenna  38  receives a signal  40  from the mobile unit module  16 . 
     Microcontrollers  34 , and/or processor device  42  can include an integrated digital signal processor (DSP) device which measures the time delays from each antenna  38  element. Device(s)  34 ,  42  can compute the direction of arrival (DOA), as well as adjust excitations of the radio frequency signals (gains and phases of the signals) to produce a radiation pattern that focuses on the signal of interest (SOI) while tuning out any signal-not-of-interest (SNOI). 
     The time difference of the signal arriving at the two antenna  38  elements can be written as
 
Δ t =( t   1   −t   2 )=Δ d/v   0   =d  cos(θ)/ v   0   (1)
 
where v 0  is the speed of light in free-space. This equation can be rewritten as
 
cos(θ)= v   0   /d Δt=v   0   /d ( t   1   −t   2 )  (2)
 
or
 
(θ)=cos −1 ( v   0   /d Δt )=cos −1   [v   0   /d ( t   1   −t   2 )].  (3)
 
     As a result, the angle of incidence θ (DOA) can be determined by ascertaining the time delay between the two elements Δt=(t 1 −t 2 ), and the geometry of the antenna array consisting of a linear array of two antenna  38  elements with a spacing d between the elements. 
     Turning to  FIG. 5 , a logical flow chart diagram of an example operation  56  of system  10  is depicted. Operation  56  includes an example verification process for determining that a radio frequency signal  40  is valid to open door  14 . Operation  56  begins (step  58 ) and the logic diverges based on whether the antenna block module  28  is a fixed or mobile unit (step  60 ). If fixed (step  62 ), microcontroller  34  powers up the transceiver  36  (step  64 ) and an embedded crystal oscillator (step  66 ). The fixed unit  20  transmits a fixed unit signal which is received by a mobile unit  16  (step  68 ). If the fixed unit  20  is in range of a transmitted mobile unit signal (step  70 ), and the mobile unit code transmitted in the signal is determined to be valid (step  72 ), then microcontroller  42  sends a control signal to switch  44  to open the door  14  (step  74 ). The fixed unit  20  then powers down the crystal oscillator (step  88 ) and transceiver (step  90 ). 
     Returning to step  60 , if the board type is mobile (step  76 ), microcontroller  34  embedded in the mobile unit  16  also powers up the mobile transceiver  36  (step  78 ) as well as the embedded crystal oscillator (step  80 ). If the mobile unit  16  determines that the fixed unit code transmitted in the signal is valid (step  84 ), then microcontroller  34  instructs transceiver  36  in mobile unit  16  to send a door open code to the fixed unit  20  (step  86 ). The mobile unit  16  then powers down the crystal oscillator (again, step  88 ) and transceiver (again, step  90 ). 
       FIG. 6  illustrates an example method  92  of operation to actuate and open a door in accordance with the present invention. As previously described, a fixed unit module  20  operates, in one embodiment, to continually transmit a radio frequency signal which is received by a mobile unit  16 . Method  92  begins (step  94 ) with the mobile unit  16  receiving the RF transmission by the fixed unit  20  (step  96 ). In one example, the mobile unit  16  can utilize a circuit which causes the mobile unit  16  to operate in a low-power consuming state yet capable of receiving radio frequency transmissions. Once the mobile unit  16  receives a radio frequency transmission of the appropriate specification, the circuit may cause the mobile unit  16  to awake, powering the transceiver  36  and associated subcomponents of antenna block module  28 . In another embodiment, the mobile unit  16  can use an entirely separate system to receive appropriate radio frequency transmissions to indicate that the mobile unit  16  is in close proximity to a remote door actuator and opener and to power on appropriate components of the mobile unit  16  in response. 
     Whether the mobile unit  16  utilizes a separate circuit, a separate system or otherwise, the microcontroller  34  in the mobile unit  16  detects the receipt of the radio frequency (step  98 ). In response, the mobile unit  16  directs the transceiver  36  integrated into mobile unit  16  to send a second radio frequency signal (step  100 ). The second radio frequency signal can include a mobile unit code or other specialized information which is verified by the fixed unit  20  (see, e.g.,  FIG. 5 , steps  72 ,  86 ) for security purposes or otherwise. Once the second signal is transmitted, the respective antenna blocks  28  in fixed unit  20  receive the signal (step  102 ). As previously described, the signal is received by a first and second antenna  38  integrated into fixed unit  20  at different times. Microcontrollers  34  integrated into fixed unit  20  receive and process the second signal, and send a control signal to the processing component  42  where time-difference-of-arrival (TDOA) measurements of the received second signal are calculated (step  104 ). 
     As a next step, the processing component  42  analyzes the TDOA measurements to calculate the direction of arrival (DOA) of the user (step  106 ). The calculated DOA is compared against a predefined, stored range of DOAs in the fixed unit or elsewhere (step  108 ). If a match is obtained, a control signal is sent by the processing component  42  to switch  44  and thereby to door motor  46  to open the door (step  110 ). The method  92  then ends (step  112 ). 
     While one or more embodiments of the present invention have been illustrated in detail, the skilled artisan will appreciate that modifications and adaptations to those embodiments may be made without departing from the scope of the present invention as set forth in the following claims.