Electric-drive motor vehicles, systems, and control logic for predictive charge planning and powertrain control
10759298 ยท 2020-09-01
Assignee
Inventors
- Yue-Yun Wang (Troy, MI)
- Junfeng Zhao (Troy, MI, US)
- Suresh Gopalakrishnan (Troy, MI)
- Yiran HU (Shelby Township, MI, US)
- Norman K. Bucknor (Troy, MI)
Cpc classification
B60W10/08
PERFORMING OPERATIONS; TRANSPORTING
B60L58/21
PERFORMING OPERATIONS; TRANSPORTING
B60L2250/28
PERFORMING OPERATIONS; TRANSPORTING
B60L58/12
PERFORMING OPERATIONS; TRANSPORTING
B60W20/12
PERFORMING OPERATIONS; TRANSPORTING
Y02E60/10
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B60L2260/52
PERFORMING OPERATIONS; TRANSPORTING
B60W20/13
PERFORMING OPERATIONS; TRANSPORTING
H01M2220/20
ELECTRICITY
Y02T90/12
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B60W10/26
PERFORMING OPERATIONS; TRANSPORTING
International classification
B60L53/64
PERFORMING OPERATIONS; TRANSPORTING
B60W20/13
PERFORMING OPERATIONS; TRANSPORTING
B60L58/21
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Presented are intelligent vehicle systems and control logic for predictive charge planning and powertrain control of electric-drive vehicles, methods for manufacturing/operating such systems, and electric-drive vehicles with smart charge planning and powertrain control capabilities. Systems and methods of AI-based predictive charge planning for smart electric vehicles use machine-learning (ML) driver models that draws on available traffic, location, and roadway map information to estimate vehicle speed and propulsion torque requirements to derive a total energy consumption for a given trip. Systems and methods of AI-based predictive powertrain control for smart hybrid vehicles use ML driver models with deep learning techniques to derive a drive cycle profile defined by a preview route with available traffic, geopositional, geospatial, and map data. ML-generated driver models are developed with collected data to replicate driver behavior and predict the drive cycle profile, including predicted vehicle speed, propulsion torque, and accelerator/brake pedal positions for a preview route.
Claims
1. A method for controlling operation of an electric-drive motor vehicle, the electric-drive motor vehicle including a traction motor operable to propel the motor vehicle and a resident vehicle controller programmed to regulate operation of the traction motor, the method comprising: determining, via the resident vehicle controller, a vehicle origin and a vehicle destination for the motor vehicle; conducting a geospatial query to identify a designated route corresponding to the vehicle origin and vehicle destination; receiving, from a memory-stored map database, road-level data associated with the designated route; determining, based on the road-level data and roadway traffic and disturbance data for the designated route, a predicted motor speed of the traction motor for the designated route; estimating a predicted motor torque of the traction motor by applying a machine-learning driver model as a function of accelerator pedal position to the predicted motor speed; integrating the predicted motor torque to calculate a total motor energy usage for the traction motor to propel the motor vehicle across the designated route from the vehicle origin to the vehicle destination; and transmitting, via the resident vehicle controller, a command signal to a resident vehicle subsystem to execute a control operation based on the total motor energy usage.
2. The method of claim 1, wherein the motor vehicle further includes a power inverter module and/or an AC-DC converter each operable to modulate a voltage transmitted to or from the traction motor, the method further comprising: calculating an inverter/converter energy loss as a function of the predicted motor speed and the predicted motor torque for the designated route, wherein the command signal to execute the control operation is further based on the inverter/converter energy loss.
3. The method of claim 1, further comprising: calculating a motor energy loss of the traction motor as a function of the predicted motor speed and the predicted motor torque for the designated route, wherein the command signal to execute the control operation is further based on the motor energy loss.
4. The method of claim 1, further comprising: calculating an estimated auxiliary device energy usage for one or more in-vehicle electronic devices operated during the designated route, wherein the command signal to execute the control operation is further based on the estimated auxiliary device energy usage.
5. The method of claim 1, further comprising: calculating an estimated autonomous-driving electronics energy usage for one or more in-vehicle sensors, cameras and/or processors operated during the designated route, wherein the command signal to execute the control operation is further based on the estimated autonomous-driving electronics energy usage.
6. The method of claim 1, wherein integrating the predicted motor torque includes determining the total motor energy usage as E.sub.MGU, the total motor energy usage E.sub.MGU being calculated as:
E.sub.MGU=.sub.A.sup.BT.sub.MGUdtE.sub.RGN where is the predicted motor speed, T.sub.MGU is the predicted motor torque, A and B are indicia of the vehicle origin and vehicle destination, respectively, and E.sub.RGN is a total regenerated energy.
7. The method of claim 1, wherein the motor vehicle further includes a traction battery pack operable to power the traction motor, the method further comprising determining a remaining battery energy E of the traction battery pack when the motor vehicle reaches the vehicle destination, the remaining battery energy E being calculated as:
E=.sub.a.sup.SOCV.sub.ocdSOCEp(A:B)E(T).sub.battloss where a is a minimum state of charge (SOC) to maintain the traction battery pack in a healthy state, V.sub.OC is an open circuit voltage of the traction battery pack, Ep(A:B) is a predicted total energy usage, and E(T).sub.battloss is a battery energy loss of the traction battery pack as a function of battery temperature T.
8. The method of claim 1, further comprising: calculating, based on the total motor energy usage, a predicted total load current for the motor vehicle to traverse the designated route from the vehicle origin to the vehicle destination, wherein the command signal to execute the control operation is further based on the predicted total energy usage.
9. The method of claim 8, wherein the motor vehicle further includes a traction battery pack operable to power the traction motor, the method further comprising determining a remaining state of charge SOC(B) of the traction battery pack, the remaining state of charge SOC(B) being calculated as:
10. The method of claim 1, wherein the motor vehicle further includes a traction battery pack operable to power the traction motor, the method further comprising: calculating, based on the total motor energy usage, a predicted total energy usage for the motor vehicle to traverse from the vehicle origin to the vehicle destination; determining if a current state of charge (SOC) of the traction battery pack is greater than the predicted total energy usage; and responsive to a determination that the current SOC is not greater than the predicted total energy usage, conducting a second geospatial query to identify an alternative route corresponding to the vehicle origin and vehicle destination.
11. The method of claim 10, wherein the resident vehicle subsystem includes a vehicle navigation system with an electronic display device, and wherein the control operation includes displaying, via the electronic display device, the alternative route contemporaneous with an indication that the current SOC is insufficient for the motor vehicle to reach the vehicle destination using the designated route.
12. The method of claim 1, wherein the resident vehicle subsystem includes an Advanced Driver Assistance System (ADAS) module operable to govern driving of the motor vehicle, and wherein the control operation includes implementing a set of enhanced low-energy-consumption driving rules.
13. The method of claim 1, wherein the resident vehicle subsystem includes an autonomous driving system module operable to automate driving of the motor vehicle, and wherein the control operation includes disabling automated driving of the motor vehicle.
14. The method of claim 1, wherein the resident vehicle subsystem includes a vehicle navigation system with an electronic display device, and wherein the control operation includes saving, in a memory-stored map database, the total motor energy usage in connection with the designated route and displaying, via the electronic display device, the designated route with an indication of the total motor energy usage.
15. An electric-drive motor vehicle comprising: a vehicle body; a plurality of road wheels attached to the vehicle body; a traction motor attached to the vehicle body and configured to drive at least one of the road wheels and thereby propel the motor vehicle; a traction battery pack attached to the vehicle body and electrically coupled to the traction motor to power the traction motor; a vehicle navigation system attached to the vehicle body and including a location tracking device, an input device, and an electronic display device; and a resident vehicle controller attached to the vehicle body and programmed to: determine, via the location tracking device and the input device of the vehicle navigation system, a vehicle location and a vehicle destination for the motor vehicle; determine, via the vehicle navigation system, a designated route corresponding to the vehicle origin and vehicle destination; determine, via a remote computing resource service from a memory-stored map database, road-level data associated with the designated route; determine, via the remote computing resource service based on the road-level data and roadway traffic and disturbance data for the designated route, a predicted motor speed of the traction motor for the designated route; determine, via the remote computing resource service, a predicted motor torque of the traction motor by applying a machine-learning driver model as a function of accelerator pedal position to the predicted motor speed; determine, via the remote computing resource service by integrating the predicted motor torque, a total motor energy usage for the traction motor to propel the motor vehicle across the designated route from the vehicle origin to the vehicle destination; and transmit a command signal to a resident vehicle subsystem to execute a control operation based on the total motor energy usage.
16. The electric-drive motor vehicle of claim 15, further comprising a power inverter module and/or an AC-DC converter each operable to modulate a voltage transmitted to or from the traction motor, wherein the resident vehicle controller is further configured to: calculate, via the remote computing resource service, an inverter/converter energy loss as a function of the predicted motor speed and predicted motor torque for the designated route, wherein the command signal to execute the control operation is further based on the inverter/converter energy loss.
17. The electric-drive motor vehicle of claim 16, wherein the resident vehicle controller is further configured to: calculate, via the remote computing resource service, a motor energy loss of the traction motor as a function of the predicted motor speed and the predicted motor torque for the designated route, wherein the command signal to execute the control operation is further based on the motor energy loss.
18. The electric-drive motor vehicle of claim 15, wherein the resident vehicle controller is further configured to: calculate, via the remote computing resource service, an estimated auxiliary device energy usage for one or more in-vehicle electronic devices operated during the designated route, wherein the command signal to execute the control operation is further based on the estimated auxiliary device energy usage.
19. The electric-drive motor vehicle of claim 15, wherein the resident vehicle controller is further configured to: calculate, via the remote computing resource service, an estimated autonomous-driving electronics energy usage for one or more in-vehicle sensors, cameras and/or processors operated during the designated route, wherein the command signal to execute the control operation is further based on the estimated autonomous-driving electronics energy usage.
20. The electric-drive motor vehicle of claim 15, wherein the resident vehicle controller is further configured to: calculate, via the remote computing resource service based on the total motor energy usage, a predicted total load current for the motor vehicle to traverse the designated route from the vehicle origin to the vehicle destination, wherein the command signal to execute the control operation is further based on the predicted total energy usage.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5) The present disclosure is amenable to various modifications and alternative forms, and some representative embodiments are shown by way of example in the drawings and will be described in detail herein. It should be understood, however, that the novel aspects of this disclosure are not limited to the particular forms illustrated in the above-enumerated drawings. Rather, the disclosure is to cover all modifications, equivalents, combinations, subcombinations, permutations, groupings, and alternatives falling within the scope of this disclosure as encompassed by the appended claims.
DETAILED DESCRIPTION
(6) This disclosure is susceptible of embodiment in many different forms. Representative embodiments of the disclosure are shown in the drawings and will herein be described in detail with the understanding that these representative examples are provided as an exemplification of the disclosed principles, not limitations of the broad aspects of the disclosure. To that extent, elements and limitations that are described, for example, in the Abstract, Introduction, Summary, and Detailed Description sections, but not explicitly set forth in the claims, should not be incorporated into the claims, singly or collectively, by implication, inference or otherwise.
(7) For purposes of the present detailed description, unless specifically disclaimed: the singular includes the plural and vice versa; the words and and or shall be both conjunctive and disjunctive; the words any and all shall both mean any and all; and the words including, containing, comprising, having, and the like, shall each mean including without limitation. Moreover, words of approximation, such as about, almost, substantially, approximately, and the like, may be used herein in the sense of at, near, or nearly at, or within 0-5% of, or within acceptable manufacturing tolerances, or any logical combination thereof, for example. Lastly, directional adjectives and adverbs, such as fore, aft, inboard, outboard, starboard, port, vertical, horizontal, upward, downward, front, back, left, right, etc., may be with respect to a motor vehicle, such as a forward driving direction of a motor vehicle when the vehicle is operatively oriented on a normal driving surface.
(8) Referring now to the drawings, wherein like reference numbers refer to like features throughout the several views, there is shown in
(9)
(10) The vehicle charging station 20 may employ any heretofore and hereinafter developed type of wired and wireless charging technology, including inductive charging, radio charging, and resonance charging, as some non-limiting examples. In accordance with electromagnetic induction charging technology, the representative wireless charging pad 24 of
(11) Traction battery pack 14 stores energy that can be used for propulsion by the electric machine(s) 16 and for operating other vehicle electrical systems. The traction battery pack 14 is communicatively connected (wired or wirelessly) to one or more vehicle controllers, represented in
(12) Vehicle charging station 20 of
(13) As part of the vehicle charging process, the electric-drive vehicle 10 may monitor wired/wireless charging availability, wireless power quality, and other related issues that may affect vehicle charging. According to the illustrated example, the vehicle ECU 26 of
(14) The representative vehicle 10 of
(15) With continuing reference to
(16) With reference now to the flowchart of
(17) Method 100 begins at terminal block 101 with processor-executable instructions for a programmable controller or control module or similarly suitable processor or server computer to call up an initialization procedure for a predictive charge planning protocol that provides more accurate EV travel range estimates, optimizes electrical system energy usage, and helps to increase battery operational life. This routine may be executed in real-time, continuously, systematically, sporadically and/or at regular intervals, for example, each 100 milliseconds, etc., during ongoing vehicle operation. As yet another option, terminal block 101 may initialize responsive to a user command prompt or a broadcast prompt signal received from a backend or middleware computing node tasked with collecting, analyzing, sorting, storing and distributing vehicle data. As part of the initialization procedure at block 101, for example, resident vehicle telematics unit 40 may execute a navigation processing code segment, e.g., to obtain vehicle data (e.g., geospatial data, speed, heading, acceleration, timestamp, etc.), and optionally display select aspects of this data to an occupant of the vehicle 10. The occupant my employ any of the HMI input controls 48 to then select a desired origin and/or destination for the vehicle. It is also envisioned that the ECU 26 or telematics unit 42 processors receive vehicle origin and vehicle destination information from other sources, such as a server-class computer provisioning data exchanges for the cloud computing system 44 or a dedicated mobile software application operating on a smartphone or other handheld computing device.
(18) Once a vehicle origin (starting position) and a vehicle destination (ending position) are confirmed at process block 101, the method 100 executes a geospatial query at input/output block 103 to identify location-specific geographic information. By way of example, and not limitation, the query conducted at block 103 may utilize the vehicle's real-time location information (i.e., a set of GPS-generated geodetic datum) and temporal information (i.e., a vehicle timestamp) to identify a designated route for traversing from the vehicle origin to vehicle destination. Geospatial information may include, in some non-limiting examples, shoulder location data, road center location data, road boundary location and geometry data, intersection midpoint location data, etc. Rather than identify a single route option, the geospatial query of input/output block 103 may identify multiple preview routes corresponding to the vehicle's start and end positions. Method 100 thereafter accesses an OPENSTREETMAP (OSM) data service 105 or similarly suitable mapping database to lookup road-level data associated with each route. This baseline road-level information may include the interconnecting segments that form a given route, a name for each road segment, a speed limit for each road segment, lane alignment information, traffic light locations, stop sign positions, gradients, etc.
(19) After establishing a vehicle origin, destination and at least one designated/preview route, and then aggregating relevant road-level data and roadway traffic and disturbance data, the method 100 begins to implement eDrive energy consumption models, auxiliary device energy consumption models, autonomous device energy consumption models, etc., to build a holistic simulation of total vehicle energy consumption to reach the desired vehicle destination. Process block 107, for example, provides memory-stored, processor-executable instructions to calculate a predicted motor energy usage of a traction motor (e.g., electric motor-generator(s) 16 of
=k(r,Gr)Vp
where k is a function of gear ratio Gr and tire radius r. It may be desirable, for at least some applications, to utilize deep learning neural network (DNN) techniques for a driver model to predict vehicle speed, desired propulsion torque, and other dynamic driving behaviors for a given route. It should be appreciated, however, that other forms of driver models may be utilized, including Long Short Term Memory (LSTM) neural network models, statistical models (e.g., Markov chain), Hidden Markov Model (HMM), nonlinear regression models, etc.
(20) From a predicted desired propulsion torque Tq.sub.des estimated through a ML-based driver model as a function of pedal position, Tq.sub.des=f(pedal), the system is able to calculate a predicted motor torque T.sub.MGU(A:B) for the preview route under investigation. Through integration, the system calculates a predicted total motor energy usage as E.sub.MGU:
E.sub.MGU=.sub.A.sup.BT.sub.MGUdtE.sub.RGN
where A and B are indicia of the vehicle origin and vehicle destination, respectively, and E.sub.RGN is a total regenerated energy for the preview route. During a braking operation, ECU 26, e.g., through implementation of a motor control module (MCM) and battery control module (BCM), may operate the electric motor(s) 16 to recover energy from slowing the vehicle 10 and store the energy in the EVB traction battery pack 14 through a regenerative braking operation. Actual motor energy usage may be higher than a predicted total motor energy usage E.sub.MGU since the motor is likely not 100% efficient. To correct for this issue, predicted total motor energy usage E.sub.MGU can be divided by an term, which is a function of motor speed/torque.
(21) At process block 109, the method 100 calculates an inverter/converter energy loss as a function of the predicted motor speed and predicted motor torque. Such inverter/converter energy loss results from the electrified powertrain employing a power inverter module or an AC-DC converter to operate the traction motor and battery pack during the designated route. Vehicle 10 may employ a power inverter module to modulate a DC voltage received from the traction battery pack 14, and output an AC voltage suitable for powering the electric motor(s) 16. By comparison, an AC-DC converter may be used as a battery charger or onboard charging module (OBCM) to convert an AC charging voltage from an off-board AC power supply (e.g., vehicle charging station 20) or the motors 16 operating in regenerative mode into a DC voltage suitable for use by the battery pack and other DC devices. Method 100 then calculates a motor energy loss as a function of predicted motor speed and torque at process block 111. Motor energy losses may result from several factors, such as: (1) resistive losses in the stator windings; (2) hysteresis losses in the stator cores; and (3) uncaptured high-frequency electrical energy reflected back from the coils.
(22) With continuing reference to
(23) Method 100 continues to summation operation 119 with processor-executable instructions to aggregate all predicted values of the ML-based energy consumption models executed at process blocks 107, 109, 111, 113, 115 and 117 and thereby derive a predicted total energy usage Ep(A:B). Once amassed, total energy usage Ep(A:B) is applied at process block 121 to calculate an estimated remaining battery energy E of the traction battery pack 14 when the motor vehicle 10 reaches its destination. Remaining battery energy E may be calculated as:
(24)
where a is a calibrated minimum battery SOC to maintain a traction battery pack in a healthy state, SOC(A) indicates a current SOC at a current location A, V.sub.OC(SOC) is an open circuit voltage of the traction battery pack as a function of SOC, E(T).sub.battloss is a battery energy loss of the traction battery pack as a function of battery temperature T, and Q is the battery pack energy capacity. In this example, the first integration .sub.a.sup.SOC(A)V.sub.oc(SOC)dSOC calculates an estimated remaining battery energy of the traction battery pack 14 at the vehicle's current location A or, when not synonymous, at the desired route's starting position, used all the way to the minimum energy a being sustained. Alternatively, an estimated remaining battery energy E may be calculated as:
E=(SOC(A)a)QEp(A:B)E(T).sub.battloss
If the SOC of a battery is known, the battery energy in terms of Ampere-hours (Ah) may be calculated as a Total Capacity *% SOC. Battery open circuit voltage V.sub.OC is a strong function of SOC, which makes the integral nonlinear; open circuit voltage V.sub.OC may be considered to have a one-to-one relationship with SOC.
(25) After calculating the remaining battery energy E, method 100 continues to decision block 123 to determine if there is a sufficient amount of battery power for the motor vehicle 10 to reach the desired destination using the designated route. This determination may generally comprise ascertaining whether or not the traction battery pack's current SOC is greater than the predicted total energy usage by at least a calibrated percentage or value. In a more specific example, decision block 123 will ascertain whether or not the predicted remaining battery energy E is greater than a calibrated charge sustaining value Thd, which is derived experimentally to prevent a traction battery pack from fully discharging and, thus, helping to maintain a longer battery life. Responsive to a determination that the remaining battery energy E is in fact greater than the calibrated charge sustaining value Thd and, thus, there is sufficient battery power for the motor vehicle 10 to reach the desired destination using the designated route (block 123=YES), the method 100 may proceed to terminal block 125 and thereafter terminate without taking any preventative or remediating action. The method 100 may thereafter loop back to terminal block 101 and run in a continuous loop.
(26) Conversely, upon determining that the remaining battery energy E is not greater than the calibrated charge sustaining value Thd and, thus, there is an insufficient amount of battery power for the motor vehicle 10 to reach the desired destination using the designated route (block 123=NO), the method 10 proceeds to process block 127 with memory-stored, processor-executable instructions for the resident vehicle controller 26 to automatically issue one or more command signals to a resident vehicle subsystem to execute one or more preventative or remediating control operations. For instance, the method 100 may return to OSM data service 105 and retrieve road-level data associated with one or more alternative routes (reroutes), each of which may be evaluated as a respective preview route in accordance with the methodology 100 of
(27) As an additional or alternative option, process block 127 may provide instructions for the ECU 26 to coordinate with a powertrain control module (PCM) to implement a set of enhanced low-energy-consumption driving rules, such as setting the vehicle 10 into eco-driver mode that limits vehicle speed and motor torque. In this regard, the ADAS module may automate one or more predetermined driving maneuvers to help preserve battery charge, including initiating adaptive cruise control (ACC) set at a calibrated speed that has been verified to optimize battery usage. It may be desirable, for at least some applications, to disable full autonomous driving of the motor vehicle for the duration of the route. This will eliminate the additional toll placed on a vehicle's electrical system to power the various sensors, hardware components and processors necessary to automate vehicle driving. Total motor/vehicle energy usage for each preview route may be saved in a resident or remote memory-stored map database; optionally, the resident vehicle navigation system's display device may display each route with an indication of its corresponding total motor/vehicle energy usage.
(28) With reference now to the flowchart of
(29) In general, method 200 predicts total vehicle energy consumption of an EV to complete a designated route using a common EV model that is calibrated to a specific vehicle platform of the EV under analysis. The method 200 attempts to simulate the entire electrical drive system, such as an electric vehicle battery (EVB) 214, electric traction motor(s) 216, converter and inverter module 260, motor controller 262, auxiliary power module 264, and autonomous driving power module 266with all component efficiency losses. Total current load of the EV may be an aggregation of inverter current I.sub.inv, auxiliary device current I.sub.apm, motor current I.sub.mgu, and autonomous driving device current I.sub.aut. The auxiliary power module (APM) 264 of
(30) For method 200 of
(31)
where SOC(A) is a starting state of charge of the traction battery pack at the vehicle origin, C is a battery capacity, and .sub.A.sup.B I(t)dt is the predicted total load current.
(32) With reference now to the work flowchart of
(33) Method 300 of
(34) According to the illustrated example, a cloud computing resource service maintains a high-definition (HD) roadway map database and systematically amasses traffic information, crowd-sourced vehicle sensor and actuator data, real-time vehicle dynamics and operating data for a host vehicle (i.e., the vehicle under investigation), front vehicle speed data (i.e., speed of a vehicle directly in front of the host vehicle), etc., for a given preview route. Data capture events may be initiated as part of a five, ten or twenty-minute prediction cycle, or as part of a five, ten or twenty-mile prediction cycle, for example. Using a Recurrent Neural Network (RNN), the system identifies maximum speed limit data, traffic light data, roadway gradient data, stop sign location data, host and front vehicle speed data, road disturbance data (e.g., construction, collision, rain, pot holes, etc.), traffic flow data, V2X and V2V data to derive the ML driver and powertrain models for predictive powertrain control. The cloud computing resource service utilizes big data processing techniques for capturing, storing, querying, batch analyzing, and updating sets of data that are significantly voluminous and complicated such that traditional data-processing application software and resident vehicle hardware are generally inadequate to handle the data's size and complexity. Big data processing may be used for data preprocessing, information fusion, feature extraction for each driving scenario, data synchronization (e.g., discrete, continuous, etc.), and drive model learning.
(35) Based on select segments of the collected data, the cloud computing resource service develops and trains a driver model using a DNN to simulate a driver's behavior in order to predict how that driver will operate an HEV or EV for a given preview route. When developing a training route, the DNN may aggregate a complete data set for a predetermined training route, effectively collecting information signals determined to cover an entire set of relevant scenarios. If the requisite information is only partially available, the trained model can be learned to adapt to future driving scenarios. Once a driver model is trained for a particular driver, the driver's accelerator and brake pedal positions and steering angle may be predicted, along with vehicle speed and propulsion torque, for a future (10-second, 10-minute, 20-minute) drive on a preview route based on the desired destination and the corresponding road conditions. For at least some implementations, the cloud computing resource service sends an ML-generated driver model to the respective vehicle or, alternatively, only sends drive cycle profile information to the vehicle for subsequent powertrain control.
(36) For a deep-learning RNN driver model, traffic signal lamp events (e.g., red, yellow, green, etc.) may be transformed into respective digital signals with a different magnitude for each event. Likewise, each stop sign location may be transformed to a digital signal, e.g., with a zero (0) value, to indicate a stop. In this regard, turn signals may be transformed into digital values assigning, for example, 10 to a no turn, 6 to a larger radius turn, 3 to a smaller radius turn, etc. Once transformed, the signals are synchronized and the digitized traffic light/stop sign/turn signals are then defined, e.g., in a 10-second travel time or an 80-meters travel distance before their exact locations. As an example:
Input_x(t)=[Vspd_limit grade turns siglamp stop traffic flow];
Output_y(t)=[Vspd pedal]
where Input x(t) is an input vector, Output_y(t) is an output signal, Vspd_limit is a vehicle speed limit as a function of time, grade is a preview route grade elevation as a function of time, turns are the transformed turn signals, siglamp are the transformed traffic signals, stop are the transformed stop signs, and traffic flow is a preview route traffic flow as a function of time.
(37) Continuing with the above discussion, a recurrent neural network using a nonlinear auto-regressive model can be expressed as:
y(t)=f(y(t1), . . . ,y(td),x(t1), . . . , (td))
and realized by the DNN. In the representative RNN architecture using a nonlinear auto-regressive model portrayed in
(38) It may be desirable, for at least some applications, to employ a deep learning RNN driver model using a perceived vehicle speed to reduce input demission in the model. By way of example, when a driver visually perceives a turn, a stop sign, a yellow-turned-red traffic signal, a red-turned-green traffic signal, etc., the driver may interpret a final desired or perceived driving speed. Driver-perceived inputs are incorporated into a driver model as follows:
Input_x(t)=[per_v_lim grade pedal(k1)vspd(k1)];
Output_y(t)=[vspd(k)pedal(k)]
for a RNN using a nonlinear auto-regressive model:
y(t)=f(y(t1), . . . ,y(td),x(t1), . . . ,(td))
(39) The above methodology may be implemented to provide a predictive vehicle speed and a predictive vehicle torque on almost any predefined route, irrespective of route length.
(40) A Short-Distance Driver Model may be particularly suited to predicting how a driver will accelerate or decelerate a vehicle, as well as how they will follow another vehicle, on a given preview route. Short-distance driver tendency modeling and learning may process a driver's past driving trajectory to learn a specific driver's driving style, such as predicted acceleration and deceleration rates, vehicle following gap distance, reaction times, distances to traffic control devices, cruise speed control tendencies, etc. Predicted acceleration/deceleration rate may be achieved by first calculating a derivative of a vehicle speed trajectory, then calculating maximum acceleration and deceleration rates for each segment. Using this information, the Short-Distance Driver Model learns maximum (and minimum) acceleration and deceleration rates. A predicted vehicle following gap distance may be achieved by using in-vehicle sensing (e.g., Lidar or radar data) to calculate a following gap distance and, from this data, calculate an average following gap distance. Using this information, the Short-Distance Driver Model learns the average gap as the driver's gap preference. As yet a further option, a predicted driver reaction time and/or distance to a traffic control device may be derived by detecting conditions that will likely cause a driver stoppage, such as red light or a stop sign. A respective distance to each target is ascertained when the driver starts to decelerate, and the Short-Distance Driver Model learns an average distance to a complete stop after the driver begins to decelerate.
(41) After predicting a desired vehicle speed and torque profile for a given preview route, an engine control module (ECM) and powertrain control module (PCM) can optimize HEV powertrain operation by splitting propulsion torque (in any logical ratio) between engine torque output and motor torque output to help reduce fuel consumption. In this manner, HEV control for production vehicles may be calibrated as reactive, e.g., to instantaneous vehicle speed and torque demand, as well as anticipatory, e.g., to predicted vehicle speed and torque demand, to help achieve energy efficiency with SOC control for a given travel route. By using a DNN driver model, the vehicle controller is able to predict how a particular driver will likely operate a vehicle with a given vehicle mass and concomitantly generate a real-time predictive drive cycle for a predicted speed and predicted torque. With these predicted values, the ECM/PCM can optimize overall HEV energy consumption by minimizing propulsion energy consumption by splitting driver torque between engine torque and motor torque.
(42) Predictive drive cycle-based hybrid optimization may be achieved by optimizing the following cost function:
(43)
subject to the constraints:
(44)
where s is a fuel equivalence factor (electrical energy to fuel equivalence), BSFC is a brake-specific fuel consumption factor, .sub.eng is an engine speed, T.sub.eng is an engine torque, P.sub.eng is an engine power, P.sub.batt is a battery power, Q.sub.LHV is a lower heating value of fuel, V.sub.p is a predicted vehicle speed, A.sub.p is a predicted accelerator pedal position, SOC(0) is an initial battery state of charge, and f.sub.p is a penalty function to disable motor drive when SOC (state of charge) reaches minimum or maximum values. Brake-specific fuel consumption is an indicator of ICE fuel consumption efficiency, and is an indicator of a charge sustaining or a charge depleting state. P(*,*) is indicative of engine power as a function of engine speed and torque, where engine speed may be back-calculated from vehicle speed and drivetrain ratio. In addition, T.sub.qeng is a predicted desired engine torque, P.sub.MGU is a motor power, .sub.MGU is a motor speed, T.sub.qMGU is a predicted desired motor torque, and T.sub.qdes is a predicted torque from driver model.
(45) Aspects of this disclosure may be implemented, in some embodiments, through a computer-executable program of instructions, such as program modules, generally referred to as software applications or application programs executed by an onboard vehicle computer or a distributed network of resident and remote computing devices. Software may include, in non-limiting examples, routines, programs, objects, components, and data structures that perform particular tasks or implement particular data types. The software may form an interface to allow a resident vehicle controller or control module or other suitable integrated circuit device to react according to a source of input. The software may also cooperate with other code segments to initiate a variety of tasks in response to data received in conjunction with the source of the received data. The software may be stored on any of a variety of memory media, such as CD-ROM, magnetic disk, bubble memory, and semiconductor memory (e.g., various types of RAM or ROM).
(46) Moreover, aspects of the present disclosure may be practiced with a variety of computer-system and computer-network architectures, including multiprocessor systems, microprocessor-based or programmable-consumer electronics, minicomputers, mainframe computers, master-slave, peer-to-peer, or parallel-computation frameworks, and the like. In addition, aspects of the present disclosure may be practiced in distributed-computing environments where tasks are performed by resident and remote-processing devices that are linked through a communications network. In a distributed-computing environment, program modules may be located in both onboard and off-board computer-storage media including memory storage devices. Aspects of the present disclosure may therefore, be implemented in connection with various hardware, software or a combination thereof, in a computer system or other processing system.
(47) Any of the methods described herein may include machine-readable instructions for execution by: (a) a processor, (b) a controller, and/or (c) any other suitable processing device. Any algorithm, software, control logic, protocol, or method disclosed herein may be embodied in software stored on a tangible medium such as, for example, a flash memory, a CD-ROM, a floppy disk, a hard drive, a digital versatile disk (DVD), or other memory devices. The entire algorithm, control logic, protocol, or method, and/or parts thereof, may alternatively be executed by a device other than a controller and/or embodied in firmware or dedicated hardware in an available manner (e.g., it may be implemented by an application specific integrated circuit (ASIC), a programmable logic device (PLD), a field programmable logic device (FPLD), discrete logic, etc.). Further, although specific algorithms are described with reference to flowcharts depicted herein, there are many other methods for implementing the example machine readable instructions that may alternatively be used.
(48) Aspects of the present disclosure have been described in detail with reference to the illustrated embodiments; those skilled in the art will recognize, however, that many modifications may be made thereto without departing from the scope of the present disclosure. The present disclosure is not limited to the precise construction and compositions disclosed herein; any and all modifications, changes, and variations apparent from the foregoing descriptions are within the scope of the disclosure as defined by the appended claims. Moreover, the present concepts expressly include any and all combinations and subcombinations of the preceding elements and features.