Patent Application
20090256677
The following relates to a passive entry system and method for detecting triggering events from multiple distances at or near a door handle, which provides ingress and egress to a vehicle, building, or the like.
A detailed description and accompanying drawings are set forth below.
With reference to
Conventional systems utilize a mechanical key which is inserted into a cylindrical lock to allow the key holder to open the lock with a turn of the key in order to gain entry. Keyless entry systems are well known for providing an authorized user access to a vehicle, building, or the like, without the cumbersome and time-consuming manipulation of a lock with a mechanical key. Typical keyless entry systems include, for example, a keypad mounted at a door or remote keyless entry (RKE) systems for automobiles and homes.
The small controller that hangs off a car's sun visor (or integrated into an overhead console) to open and close a garage door is a common RKE device. Alternative RKE systems provide for remote control by a vehicle owner or user of vehicle security systems, door locks, trunk latch, exterior and/or interior lights, horn and/or alarms. In that regard, RKE systems for remote vehicle access and other remote operations include a remote control device or unit, which is commonly referred to as a “fob” or “key fob.” The remote control device has a transmitter, and wireless radio frequency (“RF”) signals are transmitted by transmitter of the remote control device that include commands for performing vehicle operations or functions such as unlocking the vehicle doors or starting the vehicle engine. Currently available RKE fobs are hand-held, portable devices, and may be separate units or may be part of an ignition key head.
Such RKE systems also typically include a receiver and/or device control unit installed in the vehicle. RF command signals transmitted by the remote control unit are received by the vehicle-mounted receiver and/or device control unit, and may be relayed to appropriate control circuitry, systems or subsystems in the vehicle in order to effectuate the desired operation or function. For example, the receiver and/or control unit may be provided in direct or indirect (e.g., over a vehicle bus) communication with door locking mechanisms to lock and unlock the vehicle doors in response to lock or unlock signals received from the remote unit. Similarly, the receiver and/or control unit may be provided in communication with other vehicle devices to control operation thereof in response to other signals received from the remote unit.
RKE systems may be active or passive in nature. Active entry systems require a vehicle owner or user to manually transmit a command signal, such as by actuating one or more push-buttons provided on the remote control unit. In passive entry systems, signals are automatically transmitted so that, for example, a vehicle door may be unlocked as the vehicle owner or user approaches the vehicle and/or touches the door handle to open the door, without the need for any action by the vehicle owner or user.
In that regard, in a passive keyless entry system, a remote unit, which may be referred to as a “fob” or a “card,” is typically provided with a transceiver for communicating with a transceiver and/or control unit installed in the vehicle. In such systems, the remote unit carried by an operator may be used, for example, to automatically unlock the vehicle as the operator approaches the vehicle, without the need for operation of any switch or pushbutton by the operator. Similarly, the system may further be designed to automatically lock the vehicle as the operator, carrying the remote unit, moves away from the vehicle. A vehicle-mounted transceiver and/or control unit is again provided in direct or indirect communication with control circuitry, systems or subsystems to effectuate a particular operation in response to signals received from the remote unit, such as door locking mechanisms to lock and unlock the vehicle doors.
To prevent unauthorized entry into a vehicle equipped with an RKE system, command signals from remote control units are typically encrypted, such as with a rolling-code encryption scheme where a security code is transmitted with the command signal, that code being different with every transmission. The vehicle-mounted device that receives the command signals is equipped with the same rolling-code encryption scheme in order to de-crypt a received command signal and determine which security code to expect with each command signal received. As a result, even if a command signal is intercepted by a third party, that signal cannot later be re-transmitted by the third party in order to gain entry into the vehicle, since the security code transmitted with that command signal will no longer be accepted as valid by the vehicle-mounted receiver and/or control unit.
RKE systems are referred to as “one-way” systems where communication or transmission of signals only takes place from the portable remote control device having a transmitter to the vehicle-mounted device having a receiver. However, as is again well known by those of ordinary skill, RKE systems may also be “two-way” in nature. In “two-way” RKE systems, the portable remote control device carried by the vehicle user or owner includes a transceiver, and the vehicle-mounted device also includes a transceiver. As both the remote control device and the vehicle-mounted device are capable of transmitting and receiving wireless signals, two-way communication between those devices is enabled.
Signals transmitted to or from the portable remote control device and/or the vehicle-mounted device in “two-way” RKE systems are again typically encrypted for security purposes. “Two-way” RKE systems also may be either active or passive in nature.
In “two-way” RKE systems, communication from the vehicle-mounted device or unit to the portable remote control device or unit may be for any of a number of purposes, such as for prompting a passive remote control device to transmit a signal, acknowledging the receipt of a command signal from a remote unit, or others. In that regard, the remote control device or unit may be provided with a display, such as a liquid crystal or light emitting diode display, so that the vehicle owner or user can confirm that a command signal has been received by the vehicle-mounted device or unit and that the command has been effectuated (e.g., the vehicle doors have been locked/unlocked; the vehicle engine has been started).
As mentioned above, passive entry systems differ from active entry systems in that no manipulation of buttons or switches of a remote control or key fob is necessary. Rather, a door can be unlocked as an authorized user approaches a vehicle or building. Passive entry function typically includes automatic data interrogation or identification of an operator held data medium, transponder or the like so as to ascertain whether an operator approaching a motor vehicle, for example, or about to open the vehicle's door is authorized for access. Corresponding control electronics within the vehicle conducts the interrogation or checks the identification of the operator. Additionally, passive entry systems often include one or more sensors located inside a door handle capable of detecting the presence of a person or a person's hand, in particular. In the motor vehicle example, with corresponding authorization of the operator, automatic unlocking of the vehicle takes place upon the detection of the operator's hand very near or touching the door handle.
Referring now to the drawings,
To this end, vehicle unit 16 may include a wireless control module 18 and/or a door module 24. Alternatively, wireless control module 18 and door module 24 may be separate modules electrically coupled to vehicle unit 16. Wireless control module 18 may transmit a wireless signal 20, which may be a radio frequency (“RF”) signal, that includes a command message. Wireless control module 18 may transmit wireless signal 20 a distance or range (R) from vehicle 12 in order to communicate with electronic key 14. Wireless signal 20 may be received by electronic key 14, which may be located on the person of an authorized user 22.
Likewise, electronic key 14 may itself transmit a wireless signal 20′, which may also be a radio frequency (“RF”) signal, that includes a command message. Electronic key 14 may transmit wireless signal 20′ a distance or range (R) from vehicle 12 in order to remotely perform a desired vehicle operation or function represented by the command message of wireless signal 20′. Wireless signal 20′ may also be an identification or confirmation signal indicating that electronic key 14 corresponds to vehicle 12.
Wireless signal 20′ may be received at wireless control module 18 and communicated to vehicle-mounted device unit 16, which may be mounted at any suitable location on the vehicle 12. Vehicle-mounted device unit 16 can relay the command message of the wireless signal 20′ to an appropriate vehicle function or device in order to effectuate the command, such as activating or deactivating a vehicle security system, activating or deactivating vehicle interior and/or exterior lights, and/or others. In that regard, the vehicle function or device may be, for example, a computer, microprocessor, control circuit, logical device, vehicle system, vehicle device, or vehicle subsystem, or other. Relay of the command message by vehicle-mounted device unit 16 may include translation of the command message of wireless signal 20′ into an output control signal. Vehicle-mounted device unit 16 may be provided in direct communication with a vehicle function, or may be provided in communication with a vehicle function indirectly, such as over a vehicle data or communications bus (not shown).
According to an embodiment of the present application, vehicle unit 16 and wireless control module 18 may be linked to a door module 24, as shown in
As depicted in
In the awaken state, door module 24 may be configured to detect an initial touching of the door handle 26. Consequently, door module 24 may send an unlock message unlocking the lock 32. Upon the user grabbing the door handle 26, the door latch 28 may be actuated in anticipation of the user pulling the handle 26 to open the door 30. With the door 30 unlocked, the door 30 may now be pulled open so that the user 22 can gain access to the vehicle 12.
Referring now to
Door handle 26 may further include lock 32, which can be operable in a locked or unlocked state to secure or unsecure the vehicle 12, respectively. Lock 32 corresponds to vehicle latch 28 that may be manipulated by the pulling of door handle 26 to open the door 30. Pulling the vehicle door handle 26 in the locked state prevents the latch 28 from actuating thereby precluding access to the vehicle 12. Accordingly, lock 32 and latch 28 may be in communication with the door module 24 or a part thereof. Therefore, door module 24 can control lock 32 in the appropriate state. Lock 32 may be a cylindrical lock, or alternatively, another type of suitable lock known to one of ordinary skill in the art. Lock 32 may also be provided with a plug 46 having a keyhole 48. Accordingly, lock 32 may be manipulated manually with the turn of a corresponding key to lock or unlock the vehicle 12. This allows a user to still gain access to vehicle 12 with a valid mechanical key in the event the user does not have electronic key 14, or chooses not to utilize it.
Door handle 26 may house a plurality of sensors 50 for performing the passive entry function within its interior. For example, door handle 26 may include an unsecuring sensor 52 in communication with door module 24 and proximate the rear surface 40. Touching the rear surface 40 of door handle 26 can be detected by unsecuring sensor 52 and result in the unlocking of vehicle 12, assuming the user 22 has been authorized. To this end, unsecuring sensor 52 may be a capacitive touch sensor, inductive sensor, infrared sensor, mechanical sensor, or the like. In addition to unsecuring sensor 52, the plurality of sensors 50 may include a securing sensor 54. Accordingly,
In an embodiment of the present application, door module 24 may require a lasting touching detected at both sensing electrodes. Alternatively, a lasting touching detected by only one of the sensing electrodes of securing sensor 54 may be sufficient. It should be noted, however, that securing sensor 54 may include only one sensing electrode or several sensing electrodes without departing from the scope of the present application.
Additionally, the plurality of sensors 50 of door handle 26 may include a sensor for performing a specific function not necessarily related to controlling access to the vehicle 12 through the door 30. For example, at least one of the plurality of sensors 50 may include a comfort locking sensor 56. Triggering the comfort locking sensor 56 may cause the vehicle's windows and/or sunroof to close in the event they are open. According to one embodiment of the present application, comfort locking may only be activated by the exclusive touching of comfort locking sensor 56. The simultaneous touching of other sensors or regions of door handle 26 may immediately interrupt the comfort locking function in concern for safety. To this end, door handle 26 may include special markings 58 or a slight recessed area identifying specifically where the sensing electrode of comfort locking sensor 56 is disposed. Other functional sensors provided as part of door module 24 may include sensors for activating interior or exterior lights, the vehicle's engine, heated seats, or the like.
Door handle 26 may also include a hall effect sensor 60 disposed between the movable portion of the door handle and the stationary portion of the door handle. The Hall effect refers to the potential difference, known as Hall voltage, on the opposite sides of an electrical conductor through which an electric current is flowing, created by a magnetic field applied perpendicular to the current. When the door handle 26 is pulled, the movable portion is separated from the stationary portion causing a change in the Hall voltage. Door module 24 can sense this change and, therefore, detect the pull of the door handle 26. According to an embodiment of the present application, the hall effect sensor 60 may active a door assist function. That is, triggering the hall sensor may cause a dedicated motor to rotate easing the door open. Of course, triggering the hall sensor may activate additional vehicle functions in addition to, or in place of, the door assist function.
For convenience, it may be desirable for the passive entry system 10 to consistently unlock the door for an authorized user 22 prior to the user pulling the door handle 26. In order for this to occur, the control electronics must complete its sequence of functions in less time than it takes a user to approach and pull the handle 26. A user can become annoyed when the door handle 26 must be pulled a second time in order to gain entry. Thus, a race situation occurs between the user 22 and the door module 24 when the passive entry function is initiated. In order to avoid this race situation, the passive entry function may be initiated as soon as is practicable without sacrificing security. Therefore, the passive entry function may begin prior, even if only slightly, to the touching of the handle 26 by the user 22.
Accordingly, passive entry system 10 may include a proximity sensor having a target sensing zone 34 defined by an area surrounding the door handle 26. The proximity sensor can permit detection of a hand approaching, but not yet touching the door handle 26. In order to effectuate detection of a hand in the target zone 34, the plurality of sensors 50 of door handle 26 may further include a long-distance detection sensor 62 in communication with the door module 24 and having a sensing electrode designed to detect objects at a distance from the door handle 26. The long-distance detection sensor 62 may also be a capacitive-type sensor.
Because space inside door handle 26 may be limited, it may be difficult to provide a proximity sensor capable of detecting an approaching user in the desired target zone. That is, the additional long-distance detection sensor 62, alone, may not provide sufficient detection range. According to an object of the present application, the additional long-distance detection sensor 62 may be coupled to some or all of the plurality of sensors 50 to effectively create, if only temporarily, a single long-range proximity sensor 64 capable of detecting a user entering the target zone 34. To this end, the passive entry function can be reliably initiated prior to the touching of the door handle 26 allowing the control electronics of the door module 24 to complete its sequence before the user pulls the door handle 26 in an attempt to gain entry.
In this regard,
Door module 24 may further include a controller 68 in communication with the multiplexer 66. Controller 68 may signal the multiplexer 66 to couple the plurality of sensors 50 together to effectively provide the single long-range proximity sensor 64. Upon the detection of an object in the target zone 34 by the combination of sensors 50 connected in parallel, controller 68 may then instruct the multiplexer 66 to decouple the sensors 50 for individual operation corresponding to their respective function. To this end, controller 68 may further communicate with a central vehicle computer, which in turn communicates with multiple electronic modules for performing specific vehicle functions. Alternatively, controller 68 may communicate directly with electronic modules. One example of an electronic module in direct or indirect communication with controller 68 is wireless control module 18. Thus, upon detection of a user approaching door handle 26 in the target zone 34, controller 68 may instruct wireless control module 18 to poll for a valid electronic key 14, as previously described. Assuming a valid electronic key 14 is identified, controller 68 may determine that the user is authorized to gain access to the vehicle 12. Accordingly, the plurality of sensors 50 may become operable to perform their specified individual function.
It should be noted that control of the multiplexer 66 may be performed directly or indirectly by a separate multiplexer controller 70 instead of the controller 68 itself. For example, door module 24 may include multiplexer controller 70 in direct communication with the analog multiplexer 66 or indirectly through the controller 68 without departing from the scope of the present application. The various control configurations are limited only by design choices made by one of ordinary skill in the art.
Once the door module 24 is in the decoupled state, the individual sensors 50 may be activated. Unsecuring sensor 52, for example, may detect a touching of the door handle 26 and cause controller 68 to send an unlock signal to the door lock 32. When the door handle 26 is grabbed, actuation of the latch 28 occurs enabling the door 30 to open upon the pull of the door handle 26. Conversely, if a user desires to secure an unlocked vehicle from the outside, the user may perform a lasting touching of securing sensor 54, as previously described. Upon detection of this lasting touching of the securing sensor 54, controller 68 may instruct the door 30 to be locked. Moreover, a user may desire to close the windows and/or sunroof from outside the vehicle 12 if one or more is open or partially open. In that regard, the user may activate the comfort locking function by touching the comfort locking sensor 56. Thus, controller 68 may be in direct or indirect communication with a power window or sunroof module.
Hall effect sensor 60 may be in communication with the controller 68 indirectly through the multiplexer 66 as shown in
Referring now to
While the wireless control module 18 attempts to communicate with the electronic key 14 during validation of the user, there may be the potential for a proximity sensor blind zone period identified by event 128. Event 128 may occur because when user 22 is detected in the target zone 34, wireless RF signal 20 starts transmitting. Wireless signal 20 may be a low-frequency signal, which is very large compared to the low level signals detected by a capacitive-type proximity sensor. Accordingly, the low-frequency signal can disturb the capacitive readings making them unreliable while the wireless control module 18 is transmitting and receiving.
Once the door module 24 is awakened, multiplexer 66 may be instructed to decouple the plurality of sensors 50 that form the long-range proximity sensor 64 so that the one or more functional sensors can be operable to detect individual events corresponding to their respective functions. For example, unsecuring sensor 52 may now be configured to solely detect the touching of door handle at system event 130. Hand event 132 corresponds to a user 22 touching the door handle 26. As a result, door module 24 sends an unlock message to the door lock 32 at system event 134. Meanwhile, the user 22 may grab the door handle 26 illustrated at hand event 136. As the door handle 26 is being grabbed, the door module 24 unlocks the door 30 at event 138 and actuates the latch 28 at system event 140. Accordingly, milestone 142 denotes that door 30 is now unlocked. Therefore, the user 22 may successfully open the door 30 and gain access to the vehicle 12 by pulling the door handle 26 at hand event 144.
Of course, timing diagram 110 is merely exemplary and it is contemplated that the events may not all necessarily occur in the exact order shown. Further, the timing events may be modified, rearranged, or supplemented consistent with the scope of the present application.
With reference now to
Encircling the first PCB 76 may be a second PCB 78 as shown. Second PCB 78 may be a flexible PCB or similar type PCB that can be wrapped around the first PCB 76 such that it may be disposed near the interior surfaces of the door handle 26. Second PCB 78 may include the plurality of sensors 50. In this regard, the second PCB 78 may include several sensing electrodes corresponding to the one or more sensors. A simplified, exemplary layout 80 of the second PCB 78 according to an embodiment of the present application is shown in
Although the layout of the individual sensors provided on the second PCB 78 may vary, the layout shown in
In order to extend the sensing field of the sensors 50, second PCB 78 should have as little ground paths as possible. The long-range proximity sensor 64 can be a combination of the sensors 50 of second PCB 78 coupled together in parallel by multiplexer 66. As such, the combination of these sensors provides relatively accurate long-distance detection of a hand or body approaching the vehicle 12 and entering the target zone 34.
Referring back to
While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.
