Propulsion torque distribution system that provides remedial action

Abstract

A propulsion torque distribution system for a vehicle includes a controller in electronic communication with a plurality of vehicle systems. The controller executes instructions to receive at least one or more calculation faults, one or more sensor faults, and a driver torque request. In response to receiving at least one of the one or more calculation faults and one or more sensor faults, the controller determines that a fault has occurred that affects the calculation of the primary torque request. In response to determining that a fault has occurred that affects the calculation of the primary torque request, the controller determines a severity of the fault. The controller determines a remedial state based on the severity of the fault. The remedial state indicates a corresponding action to be performed by the propulsion torque distribution system.

Description

Technical Field

[0001] The present disclosure relates to systems and methods for controlling propulsion torque distribution in a vehicle. More particularly, the present disclosure relates to a propulsion torque distribution system that controls torque distribution in a vehicle and provides remedial action in response to one or more sensor failures. Background Art

[0002] In an all-wheel drive (AWD) vehicle, each of the vehicle's tires can rotate at its own speed. For example, if the vehicle is turning, the inside tires rotate slower than the outside tires. An AWD vehicle includes a main propulsion torque distribution system that determines the torque distribution between each wheel of the vehicle. Specifically, the main propulsion torque distribution function can affect the longitudinal dynamics of the vehicle by utilizing the longitudinal grip on each wheel of the vehicle. Based on torque vectoring, the main propulsion torque distribution function can also affect the lateral dynamics of the vehicle. The torque vectoring mechanism independently distributes torque to the left and right wheels of the vehicle based on driving conditions. However, in some cases, one or more sensors that are part of the vehicle may become inoperative, or resolver errors may occur, which adversely affect the functionality of the main propulsion torque distribution system.

[0003] Therefore, while current torque split systems for AWD vehicles achieve their intended purpose, there remains a need in the art for an improved torque split system that compensates for sensor and resolver failures. There is also a need in the art for a torque split system that maintains all-wheel drive capability when sensor and resolver failures occur. Summary of the Invention

[0004] According to several aspects, a propulsion torque distribution system for a vehicle is disclosed. The vehicle includes a plurality of torque distribution motors. The propulsion torque distribution system includes a controller in electronic communication with a plurality of vehicle systems. The controller executes instructions to receive at least one or more calculation faults, one or more sensor faults, and a driver torque request, wherein the driver torque request indicates a total torque that the vehicle's propulsion system needs to generate. In response to receiving at least one of the one or more calculation faults and one or more sensor faults, the controller determines that a fault has occurred that affects the calculation of a primary torque request, wherein the primary torque request distributes the total torque among the vehicle's torque distribution motors. In response to determining that a fault has occurred that affects the calculation of the primary torque request, the controller determines a severity of the fault. The controller then determines a remedial state based on the severity of the fault, wherein the remedial state indicates a corresponding action to be performed by the propulsion torque distribution system.

[0005] In another aspect, the controller executes instructions to classify a severity of the fault into one of a plurality of fault categories, wherein a remedial state is determined based on the particular fault category.

[0006] In yet another aspect, the controller executes instructions to classify the severity of the fault into a first fault category corresponding to a minor fault requiring only notification to a vehicle operator.

[0007] In yet another aspect, the controller executes instructions to classify a severity of the fault into a second fault category corresponding to requiring replacement of the sensor input to determine the primary torque request.

[0008] In one aspect, the controller executes instructions to classify the severity of the fault into a third fault category corresponding to an inability to determine the primary torque request.

[0009] In another aspect, in response to classifying the fault as a third fault category, the controller determines a lateral acceleration estimate and a longitudinal acceleration estimate of the vehicle based on sensor data from a plurality of vehicle systems.

[0010] In yet another aspect, the controller executes instructions to compare the load wheel angular rate to a threshold wheel angular rate stored in a memory of the controller, and in response to determining that the load wheel angular rate is greater than the threshold wheel angular rate, determine that the vehicle is experiencing a countersteer event, and in response to determining that the vehicle is experiencing a countersteer event, filter the lateral acceleration estimate.

[0011] In yet another aspect, the controller executes instructions to interpolate the lateral acceleration estimate and the longitudinal acceleration estimate to determine a base front-to-rear torque split, interpolate the lateral acceleration estimate and a vehicle reference speed to determine a speed correction offset, and combine the base front-to-rear torque split with the speed correction offset to determine the torque split.

[0012] In yet another aspect, the controller executes instructions to multiply the torque split by the driver requested total torque to determine a remedial torque request to be used in place of the primary torque request.

[0013] In one aspect, the driver torque request indicates the total torque that the vehicle propulsion system is required to produce based on the accelerator pedal input.

[0014] In yet another aspect, the controller executes instructions to monitor the propulsion torque distribution system to determine when a torque shift is active, and in response to determining that the torque shift has occurred, replace the primary torque request with a remedial torque request.

[0015] In yet another aspect, a controller executes instructions to monitor the propulsion torque distribution system to determine when a torque shift is active, and in response to determining that the torque shift is active, perform a torque blending operation.

[0016] In one aspect, torque blending operation includes determining a front-to-rear torque vectoring fraction and a side-to-side torque vectoring fraction for each torque-applying electric machine that is part of the vehicle.

[0017] In another aspect, the torque blending operation includes incrementing the values of a previously calculated front-to-rear torque vectoring fraction and a previously calculated side-to-side torque vectoring fraction stored in memory by an incremental value until the value of the previously calculated front-to-rear torque vectoring fraction equals the front-to-rear torque vectoring fraction and the previously calculated side-to-side torque vectoring fraction equals the side-to-side torque vectoring fraction.

[0018] In yet another aspect, the controller executes instructions to classify a severity of the fault into a fourth fault category indicating that the primary torque request cannot be determined.

[0019] In yet another aspect, the controller executes instructions to set the remedial torque request to a constant front-to-rear torque split and replace the primary torque request with the remedial torque request.

[0020] In yet another aspect, the controller executes instructions to classify a severity of the fault into a fifth fault category corresponding to a fault that prevents the plurality of torque-split electric machines from generating torque.

[0021] In one aspect, in response to determining that the severity of the fault is classified as a fifth fault category, the controller sets the remedial torque request to zero, wherein the remedial torque request is used in place of the primary torque request.

[0022] In one aspect, a non-transitory computer-readable storage medium is readable by a processing circuit and stores instructions that, when executed by the processing circuit, perform the following method operations, the method operations comprising: receiving at least one or more calculation faults, one or more sensor faults, and a driver torque request for a vehicle, wherein the driver torque request indicates a total torque required to be generated by a propulsion system of the vehicle. In response to receiving at least one of the one or more calculation faults and the one or more sensor faults, the method operations include determining that a fault has occurred that affects calculation of a primary torque request, wherein the primary torque request distributes the total torque among torque distribution motors of the vehicle. In response to determining that a fault has occurred that affects calculation of the primary torque request, the method operations include determining a severity of the fault. The method operations also include determining a remedial state based on the severity of the fault, wherein the remedial state indicates a corresponding action to be taken by the propulsion torque distribution system.

[0023] According to several aspects, a method for operating a propulsion torque distribution system of a vehicle is disclosed, wherein the vehicle includes multiple torque distribution motors. The method includes executing instructions to receive at least one or more calculation faults, one or more sensor faults, and a driver torque request, wherein the driver torque request indicates the total torque that the vehicle's propulsion system needs to generate. In response to receiving at least one of the one or more calculation faults and one or more sensor faults, the method includes determining that a fault has occurred that affects the calculation of a main torque request, wherein the main torque request distributes the total torque among the vehicle's torque distribution motors. In response to determining that a fault has occurred that affects the calculation of the main torque request, the method includes determining a severity of the fault. The method also includes determining a remedial state based on the severity of the fault, wherein the remedial state indicates a corresponding action to be performed by the propulsion torque distribution system. The method also includes classifying the severity of the fault into one of a plurality of fault categories, wherein the remedial state is determined based on a particular fault category.

[0024] Further areas of applicability will become apparent from the description provided herein.It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

[0026] Figure 1 is a schematic diagram of a vehicle including a propulsion torque distribution system of the present disclosure, according to an exemplary embodiment;

[0027] Figure 2 is a block diagram of a fault classification module according to an exemplary embodiment. Figure 1 A portion of the propulsion torque distribution system is shown;

[0028] Figure 3 is a block diagram of an acceleration estimation module according to an exemplary embodiment. Figure 1 A portion of the propulsion torque distribution system is shown;

[0029] Figure 4 is a block diagram of a remedial torque control module according to an exemplary embodiment. Figure 1 A portion of the propulsion torque distribution system is shown;

[0030] Figure 5 is a block diagram of a torque arbitration module according to an exemplary embodiment. Figure 1 A portion of the propulsion torque distribution system is shown; and

[0031] Figure 6A computer program product comprising one or more storage media according to an exemplary embodiment is shown. DETAILED DESCRIPTION

[0032] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

[0033] refer to Figure 1 , shows a schematic diagram of an exemplary vehicle 10. Vehicle 10 is any type of motor vehicle that utilizes all-wheel drive (AWD), such as, but not limited to, a passenger car such as a sedan, a truck, a van, or a sport utility vehicle. Vehicle 10 includes a plurality of wheels 16 and a plurality of torque distribution motors 18 that control torque to wheels 16. Vehicle 10 also includes a propulsion torque distribution system 20, which includes a controller 22 in electronic communication with a main vehicle motion controller 24. Main vehicle motion controller 24 sends a main torque request T1 to controller 22. When applicable, main vehicle motion controller 24 also sends one or more computational faults 30 to controller 22. Controller 22 of propulsion torque distribution system 20 and main vehicle motion controller 24 are in electronic communication with a plurality of vehicle systems 28 and a throttle control system 32. In addition to a driver torque request 40 from throttle control system 32, controller 22 also receives a plurality of sensor inputs 34, one or more sensor faults 36, and vehicle dynamic inputs 38 from the plurality of vehicle systems 28. The driver torque request 40 indicates the total torque that the propulsion system of the vehicle 10 needs to produce based on the accelerator pedal input, and the main torque request T1 distributes the total torque among the multiple torque-split electric machines 18 of the vehicle 10 .

[0034] The main vehicle motion controller 24 receives multiple sensor inputs 34, vehicle dynamics inputs 38 from multiple vehicle systems 28, and a driver torque request 40 input from the throttle control system 32, and determines a primary torque request T1 based on these inputs. During operation of the vehicle 10, the primary torque request T1 determined by the main vehicle motion controller 24 is typically sent to the torque split motor 18. However, as described below, in some circumstances, when one or more computational faults 30 and / or one or more sensor faults 36 occur, a remedial torque request T2 determined by the controller 22 of the propulsion torque split system 20 is sent to the torque split motor 18 instead of the primary torque request T1, depending on the severity of the fault. Specifically, in the presence of one or more computational faults 30 and / or one or more sensor faults 36, the controller 22 of the propulsion torque split system 20 determines remedial measures to replace the missing or corrupted data caused by the fault. In some embodiments where the fault is minor, the remedial measures may simply include providing a notification to the driver of the vehicle 10 and continuing to send the primary torque request T1 to the torque split motor 18. However, in other embodiments, the remedial measures may include replacing the primary torque request T1 with the remedial torque request T2. In an embodiment, the propulsion torque distribution system 20 may maintain all-wheel drive capability unless a fault is severe enough to prevent the plurality of torque distribution motors 18 from producing torque.

[0035] In such Figure 1 In the illustrated embodiment, the controller 22 includes a fault classification module 42, an acceleration estimation module 44, a remedial torque control module 46, and a torque arbitration module 48. However, it should be understood that different or additional modules may also be included. The fault classification module 42 receives as input one or more computation faults 30 and / or one or more sensor faults 36 from the host vehicle motion controller 24. The one or more computation faults 30 indicate that the resolver of the host vehicle motion controller 24 is unable to calculate the primary torque request T1. The sensor fault 36 indicates that one or more inputs required to determine the primary torque request T1 are unavailable. In response to receiving at least one of the one or more computation faults 30 and the one or more sensor faults 36, the fault classification module 42 determines that a fault has occurred that affects the calculation of the primary torque request T1. It should be understood that both the primary torque request T1 and the remedial torque request T2 are represented as arrays, where each value of the array corresponds to one of the torque distribution motors 18 that are part of the vehicle 10.

[0036] In response to determining that a fault that affects the calculation of the primary torque request T1 has occurred, the fault classification module 42 then determines the severity of the fault. The fault classification module 42 then determines a remedial state 50 based on the severity of the fault. The remedial state 50 indicates the corresponding action to be performed by the propulsion torque distribution system 20 based on the severity of the fault. Figure 1As shown, the remedial status 50 is sent to the primary vehicle motion controller 24, the acceleration estimation module 44, the remedial torque control module 46, and the torque arbitration module 48. As described below, depending on the severity of the fault, the propulsion torque distribution system 20 may replace the primary torque request T1 generated by the primary vehicle motion controller 24 with a remedial torque request T2.

[0037] Figure 2 Shown Figure 1 The fault classification module 42 is shown. The fault classification module 42 includes a fault classification block 52 and a remedial action selection block 54. Figure 2 In the embodiment shown, the severity of the fault is classified by the fault classification block 52. The fault classification block 52 includes a plurality of fault categories A, B, C, D, and E. In the embodiment shown in the figure, five fault categories are shown, however, it should be understood that Figure 2 This is merely exemplary in nature, and the fault classification block 52 may include any number of fault categories. Figure 1 and Figure 2 The fault classification module 42 classifies the severity of the fault into one of a plurality of fault categories A, B, C, D, and F, wherein a remediation state 50 is determined based on the particular fault category. The severity of the fault can be calculated and compared to a threshold value to classify or use the fault. In other words, the severity of the fault can be classified based on a loss function that takes into account some or all of the factors described below.

[0038] In one embodiment, the fault classification block 52 classifies the severity of the fault into a first fault category A, corresponding to a minor fault requiring only notification to the driver of the vehicle 10. That is, the propulsion torque distribution system 20 does not require corrective action, and the primary torque request T1 generated by the main vehicle motion controller 24 continues to be sent to the torque distribution motor 18. An example of a first fault category A is a faulty tire pressure sensor. The first fault category A corresponds to a first remedial state 50A, where the first remedial state 50A includes generating a driver notification 56 indicating that one or more sensors require attention. The driver notification 56 can be any type of visual, audible, or tactile alert for alerting the driver of the vehicle 10, such as a visual indicator illuminated on the vehicle's dashboard.

[0039] In another embodiment, the fault classification block 52 classifies the severity of the fault into a second fault category B, corresponding to a fault requiring an alternative sensor input to determine the primary torque request T1. For example, if one or more sensor faults 36 indicate a wheel speed sensor failure, instead of relying directly on the wheel speed, the motor speed is used as an alternative to derive the wheel speed. This second fault category B corresponds to a second remedial state 50B, which includes determining an alternative sensor input when calculating the primary torque request T1. In one embodiment, the second remedial state 50B may also include generating a driver notification 56.

[0040] The third fault category C corresponds to a fault indicating that the main vehicle motion controller 24 cannot determine the main torque request T1, so the remedial torque request T2 is calculated and sent to the torque distribution motor 18 in place of the main torque request T1. An example of a third fault category C fault is an inertial measurement unit (IMU) fault. The third category C corresponds to a third remedial state 50C. The third remedial state 50C includes estimating the lateral acceleration estimate a of the vehicle 10 by the acceleration estimation module 44. y and the estimated longitudinal acceleration a x , which will be described in more detail below, is then determined by the remedial torque control module 46 based on the lateral acceleration estimate a of the vehicle 10 y and the estimated longitudinal acceleration a x The remedial torque request T2 is determined. In one embodiment, the third remedial state 50C may also include generating a driver notification 56 .

[0041] In yet another embodiment, the fault classification block 52 classifies the severity of the fault as a fourth fault category D, which indicates that the primary torque request T1 cannot be determined. An example of the fourth fault category D is a steering angle sensor fault. In response to classifying the fault severity as the fourth fault category D, the controller 22 sets the remedial torque request T2 to a constant front-to-rear torque split, and the remedial torque request T2 is calculated and sent to the torque split motor 18 in place of the primary torque request T1. The fourth category D corresponds to a fourth remedial state 50D. The fourth remedial state 50D includes determining the remedial torque request T2 based on the constant front-to-rear torque split, as described below. In one embodiment, the fourth remedial state 50D may also include generating a driver notification 56.

[0042] Finally, the fifth fault category E corresponds to blocking the torque distribution motor 18 ( Figure 1) torque-generating fault. In response to determining that the severity of the fault is classified as the fifth fault category E, the remedial torque request T2 is set to zero and the propulsion system of the vehicle 10 is shut down. The fifth fault category E corresponds to a fifth remedial state 50E, which includes shutting down the propulsion system of the vehicle 10. In one embodiment, the fifth remedial state 50E may also include generating a driver notification 56.

[0043] Figure 3 yes Figure 1 The acceleration estimation module 44 receives the acceleration information from the fault classification module 42 (see Figure 1 and Figure 2 ) and the remedial status 50 from the plurality of vehicle systems 28 ( Figure 1 ) as inputs. Specifically, the acceleration estimation module 44 receives the wheel angle θ, the vehicle reference speed S 参考 and vehicle reference acceleration A 参考 As sensor input 34. Figure 3 As shown, the acceleration estimation module 44 includes a decision block 60, a lateral acceleration block 62, a reverse steering detection block 64, a filtering block 66, and a longitudinal acceleration block 68. The decision block 60 receives the remedial status 50 as an input. In response to the decision block 60 determining that the remedial status 50 indicates that the severity of the fault is classified as the third fault category C, the acceleration estimation module 44 generates a lateral acceleration block 62, a reverse steering detection block 64, a filtering block 66, and a longitudinal acceleration block 68. Figure 1 The sensor input 34 received by the vehicle 10 determines the estimated value a of the lateral acceleration y and the estimated longitudinal acceleration a x That is, if the remedial state 50 indicates the third remedial state 50C, the acceleration estimation module 44 only determines the lateral acceleration estimate a of the vehicle 10. y and the estimated longitudinal acceleration a x .

[0044] The lateral acceleration module 62 receives the wheel angle θ and the vehicle reference speed S as sensor inputs 34 . 参考 As input, and using any known method based on the wheel angle θ and the vehicle reference speed S 参考 To estimate the lateral acceleration a y. The backsteering detection block 64 also receives the wheel angle θ as an input. The backsteering detection block 64 compares the load wheel angular rate, which is indicative of the rate at which the steerable wheels of the vehicle 10 are turning, to a threshold wheel angular rate. The threshold wheel angular rate is a predetermined value stored in the memory of the controller 22. In response to determining that the load wheel angular rate is greater than the threshold wheel angular rate, the backsteering detection block 64 determines that the vehicle 10 is experiencing a backsteering event. It will be appreciated that when the vehicle 10 is experiencing a backsteering event, this may adversely affect the lateral acceleration estimate a y Thus, when the backsteering detection block 64 determines that the vehicle 10 is experiencing a backsteering event, the backsteering block 64 sends a filter signal 70 to the filter block 66. The filter signal 70 instructs the filter block 66 to perform a filter on the lateral acceleration estimate a. y However, once the countersteering block 64 determines that the road wheel angular rate is less than the threshold wheel angular rate for a predetermined period of time, the filtered signal 70 is no longer provided to the filter block 66, which then sends the lateral acceleration estimate a determined by the lateral acceleration block 62. y .

[0045] Continue to refer Figure 3 The longitudinal acceleration block 68 of the acceleration estimation module 44 calculates the vehicle reference acceleration A according to any known method. 参考 To determine the estimated longitudinal acceleration a of the vehicle 10 x . refer to Figure 1 and Figure 3 , the estimated lateral acceleration a of the vehicle 10 y and the estimated longitudinal acceleration a x Both are sent to the remedial torque control module 46 of the controller 22 .

[0046] Now go to Figure 4 , when the remedial state 50 indicates that the fault classification module 42 (e.g. Figure 1 When the third remedial state 50C, the fourth remedial state 50D, or the fifth remedial state 50E is selected (as shown), the remedial torque control module 46 determines the remedial torque request T2. The remedial torque control module 46 includes a decision block 90, a third remedial state block 92, a fourth remedial state block 94, a fifth remedial state block 96, and a multiplier 98. The remedial torque control module 46 receives the remedial state 50, the lateral acceleration estimate a, and the lateral acceleration estimate b. y , longitudinal acceleration estimate a x , vehicle reference speed S 参考 and the driver torque request 40 as inputs. Specifically, decision block 90 of the remedial torque control module 46 receives as input the remedial state 50. In response to the decision block 90 determining that the remedial state 50 indicates the third remedial state 50C, a torque split 100 is determined by a third remedial state block 92.

[0047] The third remedial state block 92 includes a torque distribution block 102, a speed correction offset block 104, and an adder 106. The torque distribution block 102 receives the lateral acceleration estimate a y and the estimated longitudinal acceleration a x The torque distribution block 102 takes the lateral acceleration estimate a as input. y and the estimated longitudinal acceleration a x The lateral acceleration estimate a is interpolated into one or more lookup tables stored in memory to determine the base front-to-rear torque distribution 108. The speed correction offset module 104 receives the lateral acceleration estimate a y and vehicle reference speed S 参考 The velocity correction offset block 104 converts the lateral acceleration estimate a y and vehicle reference speed S 参考 The speed correction offset 112 is interpolated into one or more lookup tables stored in memory to determine the base front-to-rear torque split 108. The adder 106 then combines the base front-to-rear torque split 108 with the speed correction offset 112 to determine the torque split 100. The torque split 100 is then multiplied by the driver requested torque 40 to determine the remedial torque request T2.

[0048] Referring back to decision block 90 , in response to the decision block 90 determining that the remedial state 50 indicates the fourth remedial state 50D, a fourth remedial block 94 determines a torque split 100 . The fourth remedial state block 94 allocates a fixed front-to-rear torque split as the torque split 100 . The torque split 100 is then multiplied by the driver requested torque 40 to determine the remedial torque request T2 . However, in response to the decision block 90 determining that the remedial state 50 indicates the fifth remedial state 50E, the torque split 100 is set to zero. Therefore, the remedial torque split T2 is zero.

[0049] Now refer to Figure 5 , shows the torque arbitration module 48. The torque arbitration module 48 includes a torque selection block 120, a decision block 124, and a torque blending block 126. The torque blending block 126 includes a torque vectoring fraction block 130, a rate limit block 132, a blending block 134, and a comparison block 136. The torque arbitration module 48 receives as input the primary torque request T1, the driver torque request 40, the remedial state 50, and the remedial torque request T2, and determines a final arbitration torque request 200 based on these inputs. The final arbitration torque request 200 is set to the primary torque request T1, the remedial torque request T2, or the intermediate blended torque request T B , as described below.

[0050] The torque selection block 120 receives as input the primary torque request T1, the remedial state 50, and the remedial torque request T2 and determines a target torque request T based on these inputs. Specifically, in response to determining that the remedial state 50 indicates the first remedial state 50A or the second remedial state 50B, the torque selection block 120 selects the primary torque request T1 as the target torque request T. Thus, the primary torque request T1 is set as the final arbitrated torque request 200. However, if the remedial state 50 indicates the third remedial state 50C, the fourth remedial state 50D, or the fifth remedial state 50E, the torque selection block 120 selects the remedial torque request T2 as the target torque request T. The torque selection block sends the target torque request T to the decision block 124.

[0051] In response to receiving the target torque request T, decision block 124 monitors the propulsion torque distribution system 20 to determine when a torque shift has occurred. A torque shift indicates a change in the value of the target torque request T. In response to determining that a torque shift has occurred, decision block 124 determines that the torque blending block 126 has performed a torque blending operation and that the target torque request T has been selected as the final arbitrated torque request 200. In response to determining that a torque shift is active, the torque blending block 126 performs a torque blending operation. When a torque shift is active, the propulsion torque distribution system 20 undergoes a torque blending operation to provide a transition between the target torque T and the current value of the final arbitrated torque request 200. For example, if the final arbitrated torque request 200 is set to the primary torque request T1 and the target torque request T is the remedial torque request T2, the torque blending operation can provide a smooth or gradual transition between the primary torque request T1 and the remedial torque request T2. The torque blending operation can prevent sudden, abrupt changes in torque request values and maintain vehicle stability.

[0052] The torque blending operation includes determining by the torque vectoring fraction block 130 that each of the torque split motors 18 ( Figure 1 ) of the front and rear torque vectoring fraction T 前后分数 and the left and right torque vectoring fractions T 左右分数 Front and rear torque vectoring fraction T 前后分数 The difference between the total front torque and the total rear torque is divided by the total torque generated by the torque distribution motor 18, and the left and right torque vectoring fraction T 左右分数 is the difference between the left motor torque and the right motor torque divided by the total torque. For example, in an embodiment where the vehicle 10 includes a single front torque split motor, a left rear torque split motor, and a right rear torque split motor, the torque vectoring fraction block 130 determines the front and rear torque vectoring fractions T based on equations 1 and 2, respectively. 前后分数 and the left and right torque vectoring fractions T 左右分数 :

[0053] Equation 1

[0054] Equation 2 Among them, T w Represents the left rear torque distribution motor, T y Represents the right rear torque distribution motor, T x Represents a single front torque distribution motor, T 总 Represents the total torque.

[0055] The torque vectoring fraction block 130 converts the front-to-rear torque vectoring fraction T 前后分数 and the left and right torque vectoring fractions T 左右分数 Sent to rate limiting block 132. The previously calculated front-to-back torque vectoring fraction T determined in the previous cycle 先前前后分数 and the previously calculated left and right torque vectoring fractions T 先前左右分数 is stored in the memory of the controller 22 and sent to the rate limiting block 132. The rate limiting block 132 converts the previously calculated front-to-rear torque vectoring fraction T 先前前后分数 and the previously calculated left and right torque vectoring fractions T 先前左右分数 The value of is incremented by an increment value to determine the intermediate hybrid torque request T B The increment value can be a constant value or a dynamic value. B is set as the final arbitration torque request 200. The intermediate hybrid torque request T B is also sent to the comparison block 136. The comparison block 136 compares the intermediate hybrid torque request T B is compared with the target torque request T. In response to determining the intermediate hybrid torque request T B is not equal to the target torque request T, the comparison block 136 instructs the rate limit block 132 to continue increasing the previously calculated front-to-back torque vectoring fraction T 先前前后分数 and the previously calculated left and right torque vectoring fractions T 先前左右分数 However, in response to determining the intermediate hybrid torque request T B Equal to the target torque request T, the comparison block 136 instructs the torque blending block 126 to cease performing the torque blending operation, and the target torque request T is set as the final arbitrated torque request 200 .

[0056] With reference generally to the accompanying drawings, the disclosed propulsion torque distribution system provides various technical effects and benefits to a vehicle. Specifically, the disclosed propulsion torque distribution system categorizes sensor failures based on their impact on primary propulsion torque control. Depending on the severity of the failure, the propulsion torque distribution system can still maintain all-wheel drive of the vehicle. The present disclosure also provides a method for replacing data in the event of one or more sensor failures so as to maintain the vehicle's all-wheel drive capability based on the severity of the failure. In addition, the present disclosure also provides a method for smoothly transitioning torque distribution from primary control to remedial control while still maintaining vehicle stability and throttle response.

[0057] Now refer to Figure 6 , a computer program product 300 includes one or more non-transitory computer-readable storage media 302. Computer-readable program code or logic 304 is stored on the storage medium 602 to provide and facilitate one or more aspects of the embodiments described herein. The program code or logic is created using, for example, a compiler or assembler to assemble instructions that, when executed, perform various aspects of the embodiments. When program code is created and stored on a tangible medium, it is referred to as a computer-readable medium. Some examples of computer-readable media include, but are not limited to, electronic memory modules (RAM), flash memory, and compact discs (CDs). The computer program product medium can be read by a processing circuit in a computer system for execution by the processing circuit.

[0058] Figure 1 The controllers 22, 24 shown may refer to electronic circuits, combinational logic circuits, field programmable gate arrays (FPGAs), processors (shared, dedicated, or grouped) that execute code, or a combination of some or all of the above (e.g., in a system on a chip), or a portion thereof. In addition, the controllers 22, 24 may be microprocessor-based, such as a computer having at least one processor, memory (RAM and / or ROM), and associated input and output buses. The processor may run under the control of an operating system residing in the memory. The operating system may manage computer resources so that computer program code embodied as one or more computer software applications (e.g., applications residing in the memory) may have instructions executed by the processor. In alternative embodiments, the processor may execute the application directly, in which case the operating system may be omitted.

[0059] The description of the present disclosure is merely exemplary in nature, and variations that do not depart from the gist of the present disclosure are intended to fall within the scope of the present disclosure. Such variations should not be regarded as a departure from the spirit and scope of the present disclosure.

Claims

1. A propulsion torque distribution system for a vehicle, wherein the vehicle includes a plurality of torque distribution motors, the propulsion torque distribution system comprising: A controller in electronic communication with a plurality of vehicle systems, wherein the controller executes instructions to: receiving at least one or more computational faults, one or more sensor faults, and a driver torque request, wherein the driver torque request indicates a total torque desired to be generated by a propulsion system of the vehicle; determining, in response to receiving at least one of the one or more calculation faults and the one or more sensor faults, that a fault has occurred that affects calculation of a primary torque request, wherein the primary torque request distributes the total torque among a plurality of torque-split electric machines of the vehicle; In response to determining that a fault affecting calculation of the primary torque request has occurred, determining a severity of the fault; as well as determining a remedial status based on a severity of the fault, wherein the remedial status indicates a corresponding action to be performed by the propulsion torque distribution system; classifying a severity of the fault into one of a plurality of fault categories, wherein the remedial state is determined based on the fault category, and wherein the propulsion torque distribution system maintains all-wheel drive capability of the vehicle based on the severity of the fault; classifying a severity of the fault into a third fault category, the third fault category corresponding to an inability to determine the primary torque request; In response to classifying the fault as the third fault category, determining a lateral acceleration estimate and a longitudinal acceleration estimate for the vehicle based on sensor data from the plurality of vehicle systems; comparing a load wheel angular rate to a threshold wheel angular rate stored in a memory of the controller; In response to determining that the road-bound wheel angular rate is greater than the threshold wheel angular rate, determining that the vehicle is experiencing a counter-steer event; as well as In response to determining that the vehicle is experiencing a countersteer event, the lateral acceleration estimate is filtered.

2. The propulsion torque distribution system for a vehicle according to claim 1, wherein the controller executes instructions to: The severity of the fault is classified into a first fault category corresponding to a minor fault that only requires notification to a driver of the vehicle.

3. The propulsion torque distribution system for a vehicle according to claim 1 , wherein the controller executes instructions to: A severity of the fault is classified into a second fault category corresponding to requiring an alternate sensor input to determine the primary torque request.

4. The propulsion torque distribution system for a vehicle according to claim 1 , wherein the controller executes instructions to: interpolating the lateral acceleration estimate and the longitudinal acceleration estimate to determine a base front-to-rear torque distribution; interpolating the lateral acceleration estimate and a vehicle reference speed to determine a speed correction offset; as well as The base front-to-rear torque split is combined with the speed correction offset to determine a torque split.

5. The propulsion torque distribution system for a vehicle according to claim 4, wherein the controller executes instructions to: The torque split is multiplied by the driver requested torque to determine a remedial torque request that is used in place of the primary torque request. 6 . The propulsion torque distribution system for a vehicle of claim 5 , wherein the driver torque request indicates a total torque that the vehicle's propulsion system needs to produce based on an accelerator pedal input.

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