Method for efficiently managing ignition states for keyless ignition systems for vehicles with electronic shifter and electronic securement systems

Abstract

A control system and method for a vehicle is provided. The system comprises a poly-shifter, an RF Hub, a transmission control module (TCM) and a controller. The poly-shifter is configured to be moved between operating states including Park and Non-Park positions. The RF Hub supports operational features of the vehicle. The TCM determines a lock state of a parking pawl in a transmission of the vehicle and communicates the lock state to the RF Hub. The controller is configured to determine whether a driver has exited the vehicle with the poly-shifter in a Non-Park position. The controller is further configured to power down the vehicle based on the lock state of the parking pawl being in a Park position and the driver exiting the vehicle with the poly-shifter in the Non-Park position.

Claims

1. A control system for a vehicle having an electronic shifter for a transmission, the control system comprising: a poly-shifter, the poly-shifter configured to be moved between operating states including Park and Non-Park positions; a radio frequency hub (RF Hub) that supports operational features of the vehicle; a transmission control module (TCM) that determines a lock state of a parking pawl in the transmission and communicates the lock state to the RF Hub; and a controller configured to: determine whether a driver has exited the vehicle with the poly-shifter in a Non-Park position; and power down the vehicle based on the lock state of the parking pawl being in a Park position and the determination that the driver has exited the vehicle with the poly-shifter in the Non-Park position.

2. The control system of claim 1, wherein the controller is further configured to: determine that the vehicle is in an engine auto-stop event and wherein the power down is further based on the vehicle in the engine auto-stop event.

3. The control system of claim 2, wherein the controller is further configured to: determine that the vehicle has not been keyed OFF and wherein the power down is further based on the vehicle not being keyed OFF.

4. The control system of claim 3, wherein determining that the vehicle has not been keyed OFF comprises determining that an ignition status is ON.

5. The control system of claim 1, wherein the Non-Park position comprises Drive.

6. The control system of claim 5, wherein the controller determines that the driver has exited the vehicle based on a signal received by the controller indicative of at least one of a brake pedal being released, a vehicle door being opened or a seat belt removed.

7. The control system of claim 1, wherein the controller is further configured to: subsequent to power down, determine a driver has entered the vehicle; and send a signal to a human machine interface (HMI) to communicate a message informing the driver that the poly-shifter was not properly returned to Park.

8. The control system of claim 1, wherein the controller communicates a signal to change the lock state of the parking pawl to the Park position based on the driver exiting the vehicle with the poly-shifter in the Non-Park position.

9. The control system of claim 1, wherein the Non-Park position comprises one of Drive, Reverse and Neutral.

10. The control system of claim 9, wherein the controller is further configured to: determine an ignition state to be in accessory (ACC) and wherein the controller communicates a signal to change the lock state of the parking pawl to the Park position based on the poly-shifter being in the Non-Park position and the ignition state being in the ACC state.

11. A method for powering off a vehicle having a poly-shifter, the poly-shifter configured to be moved between operating states including Park and Non-Park positions, the method comprising: determining a lock state of a parking pawl in a transmission of the vehicle; communicating the lock state to a radio frequency hub (RF Hub); determining whether a driver has exited the vehicle with the poly-shifter in a Non-Park position; and powering down the vehicle based on the lock state of the parking pawl being in a Park position and the driver exiting the vehicle with the poly-shifter in the Non-Park position.

12. The method of claim 11, further comprising: determining that the vehicle is in an engine auto-stop event and wherein the powering down is further based on the vehicle in the engine auto-stop event.

13. The method of claim 12, further comprising: determining that the vehicle has been keyed OFF and wherein the powering down is further based on the vehicle not being keyed OFF.

14. The method of claim 11, further comprising: determining that a driver has exited the vehicle based on at least one of a brake pedal being released, a vehicle door being opened or a seat belt being removed.

15. The method of claim 14, further comprising: subsequent to the powering down, determining whether a driver has entered the vehicle; and communicating a signal to a human machine interface (HMI) indicative of a message informing the driver that the poly-shifter was not properly returned to Park.

16. The method of claim 11, further comprising: communicating a signal to change the lock state of the parking pawl to the Park position based on the determination that a driver has exited the vehicle with the poly-shifter in the Non-Park position.

17. The method of claim 11, further comprising: determining an ignition state to be in accessory (ACC); and communicating a signal to change the lock state of the parking pawl to the Park position based on the poly-shifter being in the Non-Park position and the ignition being in the ACC state.

18. A method of powering off a vehicle having a poly-shifter, the poly-shifter configured to be moved between operating states including Park and Non-Park positions, the method comprising: determining a lock state of a parking pawl in a transmission of the vehicle; communicating the lock state to a radio frequency hub (RF Hub); determining whether a driver has exited the vehicle with the poly-shifter in a Park position; determining a circuit fault based on one of the poly-shifter and the lock state of the parking pawl; and powering down the vehicle based on the lock state of the parking pawl being in a Park position and the driver exiting the vehicle with the poly-shifter in the Park position.

19. The method of claim 18, further comprising: subsequent to the powering down, determining whether a driver has entered the vehicle; and communicating a signal to a human machine interface (HMI) indicative of a message informing the driver to service the transmission.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of an example vehicle control system in accordance with the principles of the present disclosure;

(2) FIG. 2A-2C illustrate various poly-stable shifters according to examples of the present disclosure;

(3) FIG. 2D illustrates a rotary style shifter according to examples of the present disclosure;

(4) FIG. 3 is a table showing exemplary sequences of events related to various scenarios causing battery draining according to prior art;

(5) FIGS. 4A and 4B is a table showing exemplary sequences of events related to a vehicle powering down to avoid the battery draining results of FIG. 3; and

(6) FIGS. 5A and 5B illustrate a flow diagram of an example control of the vehicle control system shown in FIG. 1, in accordance with the principles of the present disclosure.

DETAILED DESCRIPTION

(7) In conventional systems, shutting down electrical power in a vehicle having a poly-shifter requires the state of the poly-shifter and a transmission to match. For example, if the transmission is in Park and the poly-shifter is not in Park, the vehicle will drain the battery due to the fact that the vehicle components have full functionality which consumes vehicle power. There are various scenarios that may occur where a driver exits or leaves the vehicle thinking the vehicle is Off, but with the ignition remaining in a RUN state, causing the battery to drain without the driver's immediate knowledge. Described herein are systems and methods for shutting down a vehicle to prevent inadvertent draining of a vehicle battery. As used herein shutting down or powering off is used to mean disconnecting the battery from providing operating current to vehicle components. The present systems and methods disclose an automated solution to shut down the vehicle even with the driver forgetting to physically move the poly-shifter to Park.

(8) With initial reference to FIG. 1, an example schematic diagram of a vehicle control system is illustrated and generally identified at reference numeral 10. The vehicle control system 10 is equipped with an automatic stop-start system configured to automatically shut down and restart a vehicle engine 46. In the example embodiment, the vehicle control system 10 generally includes an automatic engine stop-start system (ESS) 12, a first controller or electronic control module (ECM) 14, a transmission control module (TCM) 18, and a shifter 20. The TCM 18 can additionally or alternatively include a hybrid control processor (HCP). In implementations, the TCM 18 can function as a park supervisory controller.

(9) In the illustrated embodiment, the automatic engine stop-start system 12 generally includes a keyless ignition (KIN) 30, a radio frequency hub (RF HUB) 32, and a second controller or body control module (BCM) 34. The RF HUB 32 and the BCM 34 are in signal communication with the ECM 14 via a CAN communication bus 38. A key fob 40 may be associated with the RF HUB 32 to enable the vehicle to be started. The KIN 30 may include a start/stop button 42 in signal communication with the RF HUB 32, which is configured to send an ignition run/start signal to the BCM 34.

(10) In general, the RF HUB 32 communicates with the BCM 34, ECM 14 and other modules to support operational vehicle features or systems. The RF HUB 32 communicates with the key fob 40 and the start/stop button 42 of the KIN 30 to determine if the driver is attempting to start the vehicle (i.e., inputs a button press indication from the start/stop button 42). The RF HUB 32 also inputs a Park position indication from the TCM 18. The vehicle is permitted to start only when the Park position indication reveals that the vehicle is in Park.

(11) As shown, the BCM 34 is also in signal/electrical communication with the ECM 14, and the TCM 18. In examples, the vehicle control system can further comprise a human machine interface (HMI) 36 that can receive inputs from a vehicle driver and display various messages to the driver related to the vehicle status. As used herein the HMI 36 can include any vehicle component that can at least display a message and/or indicator light including, but not limited to an instrument cluster, head up display, and infotainment system. The BCM 34 further communicates with vehicle sensors 37 to confirm status states of various components including vehicle doors, seat belts and other components.

(12) In the example shown, a battery 40 is electrically coupled to the vehicle control system 10. In general, the battery 40 can provide power to the vehicle systems and further provide initial cranking power to a vehicle powertrain 44 including an engine 46 and transmission 48 (and/or enable propulsion in an electrified vehicle). The TCM 18 can communicate signals to the transmission 48 related to gear shift events and gear status. The transmission 48 can include a parking pawl 50 that is configured to lock the transmission 48 from shifting when the shifter 20 is in the Park position. In examples, the park pawl 50 communicates a signal to the TCM 18 indicative of a status thereof. The vehicle can further include an accelerator pedal (not shown) and a brake pedal 52. While not specifically shown, an auxiliary battery can be utilized in addition to battery 40 to stabilize voltage during an auto-start event of the ESS system 12. Battery 40 (and auxiliary battery) are electrically coupled to the ECM 14 via a battery feed.

(13) In prior art configurations, the vehicle ignition OFF or key OFF management is controlled by the coordination of the BCM 34 and the RF Hub 32. The RF Hub 32 controls the KIN module 30 to maintain the ignition status to OFF and is based on both the shifter 20 and the transmission 48 both being in a Park position. Explained further, if one of the shifter 20 and the transmission 48 do not satisfy a state corresponding to the Park position, the ignition status remains ON and does not transition to OFF. In this regard, because the prior art configurations do not let the vehicle shutdown (ignition to OFF), due to one of the shifter 20 or transmission 48 not in Park, the vehicle ignition state remains in the accessory (ACC) or run condition causing the battery 40 to drain. While the configuration shown in FIG. 1 is a powertrain having a gasoline engine, the same principles are similarly adapted to other vehicle powertrains including, but not limited to, plug in hybrid vehicles (PHEV) as well.

(14) Turning now to FIGS. 2A-2C, various examples of the shifter 20 are shown and generally identified at 20A, 20B and 20C are shown. The shifters 20A-20C are poly-stable shifters. Poly-stable shifters do not have shifter auto position correction to Park such as when an auto-park event has occurred. In other words, the poly-stable shifters need to be physically moved to the selected gear state. If a driver does not physically move the shifter 20 to Park, the RF Hub 32 will not allow the vehicle to power down even with the transmission 48 in Park as indicated by the TCM 18. A rotary style shifter 20D is shown in FIG. 2D. The present teachings are also applicable to such rotary style shifter 20D that remains in a position other than Park where an auto position correction to Park has failed, such as due to a sensor fault.

(15) With additional reference now to FIG. 3, a table 70 showing exemplary sequences of events related to various scenarios causing battery draining according to prior art will be described. Three scenarios 100A, 1006 and 100C are shown that ultimately lead to unwanted draining of the battery 40. In scenarios 100A and 1006, the driver fails to move the shifter 20 back to Park to power down the vehicle. In other words, the shifter 20 is in a Non-Park position including one of Drive, Reverse and Neutral. As discussed below, a keying OFF event is used to mean a driver pushing the button 42 on the KIN 12. In scenario 100C, the vehicle is in Park, a signal between the park pawl 50 and the TCM 18 has failed causing an electrical fault which tells the system that the vehicle is not in Park. In all of scenarios 100A-100C, the vehicle ignition state stays ON or in ACC/Run causing the battery 40 to drain.

(16) Scenario 100A will now be described. In general, scenario 100A can occur during an engine auto-stop event (auto-shift to Park) and the driver exits the vehicle without keying OFF the vehicle. At 110A, the engine 46 is auto-stopped with the shifter 20 in Drive. At 112A, the brake pedal 52 is released and the ESS system 12 is ready to auto-start. At 114A, a vehicle door is opened. At 116A engine start is aborted, electronic securement system (ESS) is enabled and the TCM 18 engages the park pawl 50. At 118A, the ESS displays a message on the HMI 36 such as Shift to Park to Exit, Shift to Drive to Restart. At 120A, the shifter 20 remains in Drive. At 122A, the driver exits the vehicle. At 124A, the vehicle does not switch OFF and the ignition stays in run with the engine 46 Off. At 130A, the battery 40 drains.

(17) Scenario 1006 will now be described. In general, scenario 1006 can occur during a driver key OFF event where the vehicle auto-shifts to Park and exits the vehicle without moving the shifter 20 to Park. At 1106, the vehicle comes to a stop with the shifter 20 in any of R/N/D. At 1126, a driver presses the KIN button 42. At 114B, the ignition status transitions from Run to ACC. At 116B, the RCM 18 defaults to Park. At 118B a message is displayed on the HMI 36 such as Shift to Park to Start. At 120B, the shifter 20 remains at any of R/N/D. At 122B, the driver exits the vehicle. At 124B, the vehicle does not switch Off as the ignition stays in ACC with the engine 46 Off. At 1306, the battery 40 drains. High voltage batteries on PHEV's similarly drain.

(18) Scenario 100C will now be described. In general, scenario 100C can occur with a gated park switch (such as associated with the park pawl 50) faulted with a driver moving the shifter 20 to Park and the transmission 48 is also in Park. At 110C, the shifter 20 is in Park. At 112C, the TCM 18 engages the park pawl 50. At 114C, the TCM 18 has a short to battery or open circuit fault on the gated park switch. At 116C, the driver presses the KIN button 42 to switch OFF. At 118C, a message is displayed on the HMI 36 such as Service Transmission. At 120C, the shifter 20 remains in Park. At 122C, the driver exits the vehicle. At 124C, the vehicle does not switch OFF as the ignition stays in ACC with the engine 46 Off. At 130C, the battery 40 drains. High voltage batteries on PHEV's similarly drain.

(19) FIGS. 4A and 4B is a table 170 showing exemplary sequences of events related to a vehicle powering down to avoid the battery 40 draining results of FIG. 3. The same scenarios 100A-100C are repeated with reference numerals increased by 100 for Events 1-7. In FIGS. 4A and 4B, Events 8-10 are disclosed for scenarios 200A, 200B and 200C for preventing inadvertent draining of the battery 40 that would have otherwise occurred based on Events 8-9 discussed in FIG. 3.

(20) Referring specifically to scenario 200A, at 240A, the RF Hub 32 receives a signal from the TCM 18 indicative of the transmission in Park. In examples, the signal can be communicated on the CAN communication bus 38. At 242A, the vehicle powers down as per predetermined timing and the ignition state is moved to OFF. Predetermined timing is used to refer to a target elapsed time set by the BCM 34 or the ECM 14. At 250A, the HMI 36 will display a first message such as Press Brake and Push Button to Start when the driver enters the vehicle. In addition, the R or D can blink on the shifter 20. The HMI 36 can further display a second message Shift to park to start. The driver can subsequently physically move the shifter 20 to Park where the vehicle can be successfully started due to the battery 40 not being drained.

(21) Referring specifically to scenario 200B, at 240B, the RF Hub 32 receives a signal from the TCM 18 indicative of the transmission in Park. In examples, the signal can be communicated on the CAN communication bus 38. At 242B, the vehicle powers down as per predetermined timing and the ignition state is moved to OFF. Predetermined timing is used to refer to a target elapsed time set by the BCM 34 or the ECM 14. At 250B, the HMI 36 will display a first message such as Press Brake and Push Button to Start when the driver enters the vehicle. In addition, the R or D can blink on the shifter 20. The HMI 36 can further display a second message Shift to park to start. The driver can subsequently physically move the shifter 20 to Park where the vehicle can be successfully started due to the battery 40 not being drained.

(22) Referring specifically to scenario 200C, at 240C, the RF Hub 32 receives a signal from the TCM 18 indicative of the transmission in Park. In examples, the signal can be communicated on the CAN communication bus 38. At 242C, the vehicle powers down as per predetermined timing and the ignition state is moved to OFF. Predetermined timing is used to refer to a target elapsed time set by the BCM 34 or the ECM 14. At 250C, the HMI 36 will display a first message such as Press Brake and Push Button to Start when the driver enters the vehicle. In addition, the R or D can blink on the shifter 20. The HMI 36 can further display a second message Shift to park to start. The driver can subsequently physically move the shifter 20 to Park where the vehicle can be successfully started due to the battery 40 not being drained.

(23) With additional reference now to FIGS. 5A and 5B an example control method 300 carried out by the vehicle control system 10 shown in FIG. 1 will be described in accordance with the principles of the present disclosure. It will be appreciated that the logic steps can correspond to the events described above related to FIGS. 4A and 4B. At 310 control determines that the shifter 20 is in one of Reverse, Neutral or Drive with the ignition state to RUN. At 312, control determines that the shifter 20 has auto-shift to Park during an engine auto-stop event and the driver exits the vehicle without keying OFF the vehicle. At 314 control determines that the engine 46 has auto-stopped with the shifter 20 in Drive. At 316 control determines that the brake pedal 52 has been released or a door has been opened or a seatbelt removed. The determination is made based on signals received by sensors 37. At 320 control aborts engine start and vehicle securement strategies are enabled. The TCM 18 communicates a signal to the park pawl 50 to move to a Park position. At 332, control sends a signal to the HMI 36 to display a message informing the driver that the poly-shifter 20 was not properly returned to Park. By way of example only, such message can include Shift to Park to Exit, Shift to Drive to Restart. At 324, control determines that the driver has exited the vehicle with the shifter 20 in a position other than park such as Drive. At 330, the RF Hub 32 receives a signal from the TCM 18 indicative of the transmission in Park. Control powers down the vehicle in response to the signal from the TCM 18. At 332, control determines that the vehicle has powered down. Control subsequently determines that the driver has entered the vehicle and sends a signal to the HMI 36 to display a message such as Press Brake and Push Button to Start. Control can determine that a driver has entered the vehicle based on at least one of a door being opened and a seat belt being latched (based on signals from sensors 37). Control can concurrently send a signal to the shifter 20 to blink R/N/D. The TCM 18 can send a signal to the HMI 36 to display a message Shift to park to start. The driver can physically move the shifter 20 to Park and successfully start the engine 46 (due to the battery 40 not being inadvertently drained).

(24) In a second control scenario, at 342, control determines that the shifter 20 has auto-shift to Park during an engine auto-stop event and the driver exits the vehicle without keying OFF the vehicle. At 344, control determines that the vehicle has come to a stop with the shifter 20 in any of R/N/D. At 346, control determines that the driver has pressed the KIN button 42 and the ignition transitions to ACC. At 350 control communicates a signal to engage the park pawl 50. In examples, the TCM 18 can communicate the signal to the park pawl 50. At 352, control communicates a signal to the HMI 36 to display a message Shift to Park. At 354, control determines that the driver has exited the vehicle with the shifter 20 in Drive. Control then proceeds to 330 and 332.

(25) In a third control scenario, at 370, a gated park switch associated with the park pawl 50 is faulted with the driver moving the shifter 20 to Park and the transmission 48 is also in Park. At 372 control determines that the shifter 20 is in Park. At 374, control communicates a signal to engage the park pawl 50. In examples, the TCM 18 can communicate the signal to the park pawl 50. At 376, control determines there is a fault or short. In examples, control can determined that the TCM 18 has a short to the battery 40. In other examples, the TCM can determine that the gated park switch has an open circuit fault. At 378 control determines that the driver presses the KIN button 42 to OFF. At 380 control determines that the TCM 18 has set a park switch output fault. At 382 control determines that the driver presses the KIN button 42 to OFF. At 384, the RF Hub 32 receives a signal from the TCM 18 indicative of the transmission 48 in Park. Control powers down the vehicle in response to the signal from the TCM 18. At 390, control determines that the vehicle has powered down. Control subsequently determines that the driver has entered the vehicle. The driver can then successfully start the engine 46 (due to the battery 40 not being inadvertently drained). Control sends a message to the HMI indicative of the fault. In examples, the message can include Service Transmission.

(26) It will be appreciated that the term controller as used herein refers to any suitable control device(s) that is/are configured to perform at least a portion of the techniques of the present disclosure. Non-limiting examples include an application-specific integrated circuit (ASIC), one or more processors and a non-transitory memory having instructions stored thereon that, when executed by the one or more processors, cause the controller to perform a set of operations corresponding to at least a portion of the techniques of the present disclosure. The one or more processors could be either a single processor or two or more processors operating in a parallel or distributed architecture. It should also be understood that the mixing and matching of features, elements, methodologies and/or functions between various examples may be expressly contemplated herein so that one skilled in the art would appreciate from the present teachings that features, elements and/or functions of one example may be incorporated into another example as appropriate, unless described otherwise above.