Cruise control algorithm to improve fuel efficiency

Abstract

A method for controlling a vehicle speed, comprising: Receive, from a user interface, a set speed and a minimum speed; generating a first control signal indicative of a first engine torque request; controlling a vehicle to maintain the set speed in response to the first engine torque request; Detecting a vehicle pitch angle; Detecting the vehicle speed; and based on the vehicle pitch angle and vehicle speed: if the vehicle pitch angle is greater than zero degrees and the vehicle speed is greater than the minimum speed, generating a second control signal indicative of the first engine torque request and controlling the vehicle to maintain a first engine torque in response to the first engine torque request; or when the vehicle pitch angle is greater than zero degrees and the vehicle speed is less than the minimum speed, generating a third control signal indicative of a second engine torque request and controlling the vehicle to maintain the minimum speed in response to the second engine torque request.

Description

[0001] The present disclosure relates generally to vehicles, and more particularly to methods, systems, and apparatus for reducing fuel consumption of a vehicle during cruise control operation, and more particularly to a method and apparatus for maintaining a torque demand on the vehicle during an uphill climb until a minimum speed or a reduction in road grade is reached.

[0002] Cruise control is a system that automatically regulates vehicle speed. The system is a servo mechanism that takes over the vehicle's throttle to maintain the speed set by the driver. Cruise control is usually activated by user input. Once activated, the driver can set the desired speed by pressing the plus or minus buttons. The system then maintains that speed, even when the road surface is uneven or the vehicle is going uphill or downhill. Cruise control is a good way to reduce driver fatigue on long journeys. It can also help improve fuel efficiency because the vehicle maintains a constant speed without having to accelerate or brake as often.However, there are some situations where cruise control should not be used, such as in stop-and-go traffic, on slippery roads, or in areas with frequent speed changes. Because the cruise control system is set to a specific speed, a typical cruise control system can reduce fuel consumption in hilly terrain because the system uses more fuel when going uphill and brakes when going downhill to maintain the set speed.

[0003] Cruise control allows a vehicle to automatically adjust its speed to maintain a specific speed based on a user input speed. However, in currently available conventional cruise control systems, the ACC control module is programmed to maintain the set cruise speed regardless of the current road gradient or other environmental conditions when no other vehicles are nearby. For example, when the vehicle is traveling uphill, the reverse force due to gravity increases, causing the vehicle to slow down, and the cruise control system to need to apply more throttle to maintain the set speed. In some cases, this increase in the accelerator pedal pressure may be accompanied by a transmission downshift, resulting in higher engine speeds.Using the cruise control system on inclines or winding roads may cause the system to force multiple transmission shifts, which can lead to transmission fluid overheating and premature component wear. These alternating engine speeds and / or transmission shifts can be annoying for the driver and significantly reduce the vehicle's fuel efficiency.

[0004] DE 10 2010 030 346 A1 describes a method for controlling the driving operation of a motor vehicle whose drive train is largely automated and has a drive motor designed as an internal combustion engine, a stepwise or continuously variable drive transmission, and at least one separating clutch arranged between the drive motor and the drive transmission, wherein during a journey, if certain operating conditions exist and a suitable speed profile is calculated for a section of road ahead on the basis of topographical data and vehicle parameters, the drive train is opened and the journey is continued in so-called coasting mode until an abort signal occurs.To enable sailing operation, it is provided that the speed curve calculated for the case of immediate opening of the drive train is continuously determined at equidistant successive waypoints of the route and is evaluated in each case with reference to a lower limit speed and an upper limit speed, and that sailing operation is only enabled if the evaluation result is positive at a specified minimum number of successive waypoints.

[0005] DE 10 2020 103 644 A1 describes a speed control method for controlling a vehicle. The method includes receiving a set speed, a maximum permissible speed, and a minimum permissible speed by a controller of the vehicle, each of the maximum permissible speed and the minimum permissible speed being a speed limit; a drive system for generating a commanded axle torque to maintain the set speed; monitoring a current vehicle speed of the vehicle; determining a current vehicle acceleration of the vehicle; determining a time required for the vehicle to reach the speed limit; determining whether the time required for the vehicle to reach the speed limit is less than a predetermined time threshold;and in response to determining that the time required for the vehicle to reach the speed limit is less than the predetermined time threshold, instructing the vehicle's drive system to adjust the commanded axle torque;

[0006] DE 10 2012 210 317 A1 describes a method for specifying a proposal for target speeds on route sections to be traveled by a motor vehicle, comprising the following steps: providing information about a desired energy consumption for a route of the motor vehicle; providing route section information for the route sections of the route; and determining a speed profile which, depending on the route section information and the desired energy consumption, specifies the target speeds for each route section, wherein the target speeds for each route section are determined such that the energy consumption over the route corresponds to the desired energy consumption and does not exceed or fall below a predetermined speed limit.

[0007] DE 10 2010 018 335 A1 describes a cruise control system for a vehicle with a vehicle engine. To save energy, the cruise control system's control system is designed to maintain the vehicle's speed at an adjustable target speed provided the vehicle's engine power output does not exceed an adjustable maximum target power, and to reduce the vehicle's speed if necessary so that the maximum target power is not exceeded.

[0008] DE 10 2016 214 822 A1 describes methods for assisting a driver in driving a motor vehicle.The methods comprise the steps of: determining a maximum permissible driving speed in a section of road currently being travelled or expected to be travelled in the future by evaluating environmental data describing the motor vehicle environment, calculating a target maximum speed which is lower than the permissible driving speed by subtracting a predetermined reduction amount from the permissible driving speed and / or by multiplying the permissible driving speed by a predetermined scaling factor, controlling at least one indication device for outputting an indication to the driver when a current driving speed of the motor vehicle exceeds the target maximum speed and / or controlling the driving speed of the motor vehicle by a longitudinally guiding driver assistance system, wherein the target maximum speed is used as a maximum speed or a target speed for the control.

[0009] DE 10 2015 224 435 A1 describes a method for operating a motor vehicle having at least one drive motor that is operatively connected / operatively connectable to at least one drive wheel of the motor vehicle, as well as an actuatable accelerator pedal, wherein a target drive torque is specified to the drive motor depending on a position of the accelerator pedal, wherein at least one rotation rate and / or acceleration of the motor vehicle is detected by means of a measuring device.It is provided that a change in driving resistance is determined as a function of the detected rotation rate and / or acceleration, that when the change is detected, a compensation torque supplementing the target drive torque is determined as a function of the determined change, which compensation torque is necessary to keep a driving speed of the motor vehicle constant or almost constant given the detected change in driving resistance, and that the drive motor is controlled to generate the compensation torque in addition to the target drive torque.

[0010] Therefore, it is desirable to solve the above-mentioned problems to provide a fuel-efficient cruise control system. Furthermore, other desirable features and characteristics of the present disclosure will become apparent from the following detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background. Description

[0011] The invention is defined by the claims.

[0012] Presented herein are methods and systems for controlling vehicles with driver assistance systems and associated electrical systems for providing such systems, methods for manufacturing and operating such systems, and motor vehicles and other devices such as aircraft, ships, wind turbines, and other electric vehicles with on-board propulsion systems. By way of example and without limitation, various embodiments of systems for performing a cruise control algorithm, detecting a positive vehicle pitch angle, maintaining a previous engine torque, detecting a vehicle speed less than a minimum speed, and generating subsequent engine torque in response to the vehicle speed being less than a minimum speed and the vehicle pitch angle being greater than zero degrees are presented.

[0013] In at least one exemplary embodiment, a method for controlling a vehicle speed includes receiving, from a user interface, a set speed and a minimum speed, generating a first control signal indicative of a first engine torque request, controlling a vehicle to maintain the set speed in response to the first engine torque request, sensing a vehicle pitch angle, sensing the vehicle speed, generating a second control signal indicative of the first engine torque request in response to the vehicle pitch angle being greater than zero degrees and the vehicle speed being greater than the minimum speed, controlling the vehicle to maintain a first engine torque in response to the first engine torque request, generating a third control signal indicative of a second engine torque request,in response to the vehicle pitch angle being greater than zero degrees and the vehicle speed being less than the minimum speed, and controlling the vehicle to maintain the minimum speed in response to the second engine torque request.

[0014] According to another aspect of the disclosure, the set speed is received by the user interface in response to user input.

[0015] According to another aspect of the disclosure, the set speed is determined in response to a vehicle speed during activation of a cruise control system.

[0016] According to another aspect of the disclosure, the vehicle speed is controlled by a vehicle controller in response to the first engine torque request and the second engine torque request.

[0017] According to another aspect of the disclosure, the minimum speed is received from a user interface in response to user input.

[0018] According to another aspect of the disclosure, the minimum speed is a percentage of the set speed and is determined in response to user input received prior to activation of a cruise control algorithm.

[0019] According to another aspect of the disclosure, the minimum speed is determined in response to a maximum allowable speed reduction determined in response to a user input received prior to activation of a cruise control algorithm.

[0020] According to another aspect of the disclosure, the minimum speed is a default value stored in a memory when the vehicle is started up.

[0021] According to another aspect of the disclosure, this also includes deactivating an air conditioning compressor in response to the vehicle pitch angle being greater than zero degrees and the vehicle speed being greater than the minimum speed and less than the set speed.

[0022] According to another aspect of the disclosure, a cruise control system includes a user interface for receiving a set speed and a minimum speed, a pitch angle sensor for detecting a vehicle pitch angle, a speed sensor for detecting a vehicle speed, a processor for generating an engine torque request, and a vehicle controller for controlling the vehicle speed in response to the engine torque request.

[0023] According to another aspect of the disclosure, the set speed is received by a user interface in response to user input.

[0024] According to another aspect of the disclosure, the set speed is determined in response to a vehicle speed during activation of a cruise control system.

[0025] According to another aspect of the disclosure, the vehicle speed is controlled by a vehicle controller in response to the first engine torque request and the second engine torque request.

[0026] According to another aspect of the disclosure, the minimum speed is received from a user interface in response to user input.

[0027] According to another aspect of the disclosure, the minimum speed is a percentage of the set speed and is determined in response to user input received prior to activation of a cruise control algorithm.

[0028] According to another aspect of the disclosure, the minimum speed is determined in response to a maximum allowable speed reduction determined in response to a user input received prior to activation of a cruise control algorithm.

[0029] According to another aspect of the disclosure, the minimum speed is a default value stored in a memory during vehicle startup.

[0030] According to another aspect of the disclosure, this also includes deactivating an air conditioning compressor in response to the vehicle pitch angle being greater than zero degrees and the vehicle speed being greater than the minimum speed and less than the set speed.

[0031] According to another aspect of the disclosure, a vehicle control system comprises the steps of: identifying, by the processor, a target vehicle operating in the host vehicle environment and quantifying a set of target vehicle parameters about the target vehicle derived from sensed inputs; modeling, by the processor, a state estimate of the host vehicle and the target vehicle by generating a set of speed and torque calculations about each vehicle; generating, by the processor, a set of results from at least one reward function based on one or more modeled state estimates of the host and target vehicles; and correlating, by the processor, the set of results with driver behavior data adapted by RL to one or more control actions to the driver behavior data.

[0032] According to another aspect of the disclosure, the minimum speed is received from a user interface in response to user input, and the minimum speed is at least one of a user-defined speed, a percentage of the set speed, and the set speed less a maximum speed loss. Brief description of the drawings

[0033] The exemplary embodiments are described below in conjunction with the following drawings, wherein like numerals indicate like elements and wherein: Fig. 1 is a functional block diagram illustrating an autonomous or semi-autonomous vehicle with a control system that controls vehicle actions in response to a cruise control algorithm and vehicle pitch angle in a vehicle control system, in accordance with example embodiments; Fig. 2 shows an exemplary environment for using an improved cruise control system according to various embodiments; Fig. 3 is a diagram illustrating the components of a system implemented using the cruise control system fuel efficiency algorithm in accordance with various embodiments described in the Fig. 1-2, has been implemented; and Fig. 4 is a flowchart illustrating an exemplary method of using the system implemented using the cruise control fuel efficiency algorithm in accordance with various embodiments described in the Fig. 1-3, has been implemented. Detailed description

[0034] The following detailed description is merely exemplary and is not intended to limit the application and uses. Furthermore, there is no intention to be bound by any expressed or implied theory presented in the preceding technical field, background, brief summary, or the following detailed description.As used herein, the term "module" refers to any hardware, software, firmware, electronic control component, processing logic, and / or processor device, individually or in any combination, including, but not limited to: application-specific integrated circuits (ASICs), a field-programmable gate array (FPGA), an electronic circuit, a processor (collectively, dedicated, or in a group), and memory executing one or more software or firmware programs, a combinational logic circuit, and / or other suitable components that provide the described functionality.

[0035] Embodiments of the present disclosure may be described herein in terms of functional and / or logical block components and various processing steps. Such block components may be implemented by any number of hardware, software, and / or firmware components configured to perform the specified functions. For example, an embodiment of the present disclosure may utilize various integrated circuit components, such as memory elements, digital signal processing elements, logic elements, lookup tables, or the like, capable of performing a variety of functions under the control of one or more microprocessors or other control devices.Furthermore, those skilled in the art will understand that embodiments of the present disclosure may be used in connection with any number of systems and that the systems described herein are merely exemplary embodiments of the present disclosure.

[0036] For the sake of brevity, conventional techniques related to signal processing, data transmission, signaling, control, machine learning, image analysis, and other functional aspects of the systems (and the individual operating components of the systems) are not described in detail here. Furthermore, the connecting lines depicted in the various figures are intended to represent exemplary functional relationships and / or physical couplings between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may be present in an embodiment of the present disclosure.

[0037] With reference to Fig. 1, a control system 100 is connected to a vehicle 10 (also referred to herein as a "host vehicle") in accordance with various embodiments. In general, the control system (or simply "system") 100 provides for controlling various actions of the vehicle 10 (e.g., torque control) determined by reinforcement learning (RL) stored or capable of being stored in a DNN-type model that controls operation in response to data from vehicle inputs, for example, as described further below in connection with the Fig. 2 to 4 are described in more detail.

[0038] In various exemplary embodiments, system 100 provides a process that uses an algorithm that controls torque and speed in the embedded control software of a host vehicle of system 100 so that DNNs can be used for an ACC behavior prediction model. System 100 enables learning the driver preference for following distance for various target vehicles such as a target vehicle and classifying the driver preference based on driving scenarios, for example, traffic signs, stop-and-go traffic, city traffic, etc. System 100 can build a knowledge base of the target vehicle's preferences regarding following behavior using a Q-matrix by leveraging online and historical driver and environmental information.

[0039] As in Fig. 1, the vehicle 10 generally includes a chassis 12, a body 14, front wheels 16, and rear wheels 18. The body 14 is disposed on the chassis 12 and substantially encloses the components of the vehicle 10. The body 14 and the chassis 12 may together form a frame. Wheels 16-18 are each rotatably connected to the chassis 12 near a corner of the body 14. In various embodiments, the wheels 16, 18 comprise a wheel assembly that also includes respective associated tires.

[0040] In various embodiments, the vehicle 10 is autonomous or semi-autonomous, and the control system 100 and / or components thereof are integrated into the vehicle 10. The vehicle 10 is, for example, a vehicle that is automatically controlled to transport passengers from one location to another. The vehicle 10 is depicted as a passenger car in the illustrated embodiment, but it should be appreciated that any other vehicle, including motorcycles, trucks, sport utility vehicles (SUVs), recreational vehicles (RVs), watercraft, aircraft, and the like, may also be used.

[0041] As illustrated, the vehicle 10 generally includes a propulsion system 20, a transmission system 22, a steering system 24, a braking system 26, a canister emptying system 31, one or more user input devices 27, a sensor system 28, an actuator system 30, at least one data storage device 32, at least one controller 34, and a communication system 36. The propulsion system 20, in various embodiments, may include an internal combustion engine, an electric machine such as a traction motor, and / or a fuel cell propulsion system. The transmission system 22 is configured to transfer the power of the propulsion system 20 to the vehicle wheels 16 and 18 according to selectable gear ratios. According to various embodiments, the transmission system 22 may include a continuously variable automatic transmission, a continuously variable transmission, or other suitable transmissions.

[0042] The braking system 26 is configured to apply braking torque to the vehicle wheels 16 and 18. In various embodiments, the braking system 26 may include friction brakes, cable brakes, a regenerative braking system such as an electric machine, and / or other suitable braking systems.

[0043] The steering system 24 influences the position of the vehicle wheels 16 and / or 18. Although a steering wheel is shown for illustrative purposes, the steering system 24 may not include a steering wheel in some embodiments contemplated by the present disclosure.

[0044] The controller 34 includes at least a processor 44 (and a neural network 33) and a computer-readable storage device or medium 46. As mentioned above, in various embodiments, the controller 34 (e.g., its processor 44) provides data relating to a projected future path of the vehicle 10, including projected future steering instructions, in advance to the steering control system 84 for use in controlling the steering for a limited period of time in the event that communication with the steering control system 84 is unavailable. In various embodiments, the controller 34 also provides communication to the steering control system 84 via the communication system 36 described below, for example, via a communication bus and / or a transmitter (in Fig. 1 not shown).

[0045] In various embodiments, the controller 34 includes at least one processor 44 and a computer-readable storage device or medium 46. The processor 44 may be any custom or off-the-shelf processor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processor among a plurality of processors connected to the controller 34, a semiconductor-based microprocessor (in the form of a microchip or chipset), any combination thereof, or generally any device for executing instructions. The computer-readable storage devices or media 46 may include volatile and non-volatile memories, for example, read-only memory (ROM), random access memory (RAM), and keep-alive memory (KAM).KAM is a persistent or non-volatile memory that can be used to store multiple neural networks along with various operating variables while the processor 44 is off. The computer-readable storage device(s) 46 can be implemented using any number of known storage devices such as PROMs (programmable read-only memory), EPROMs (electrical PROM), EEPROMs (electrically erasable PROM), flash memory, or other electrical, magnetic, optical, or combination storage devices capable of storing data, some of which represent executable instructions used by the controller 34 in controlling the vehicle 10.

[0046] The instructions may comprise one or more separate programs, each containing an ordered list of executable instructions for implementing logical functions. The instructions, when executed by processor 44, receive and process signals from sensor system 28, perform logic, calculations, methods, and / or algorithms to automatically control the components of vehicle 10, and generate control signals that are transmitted to actuator system 30 to automatically control the components of vehicle 10 based on the logic, calculations, methods, and / or algorithms. Although in Fig. 1 only one controller 34 is shown, embodiments of the vehicle 10 may include any number of controllers 34 that communicate via any suitable communication medium or combination of communication media and that cooperate to process the sensor signals, perform logic, calculations, methods and / or algorithms, and generate control signals to automatically control features of the vehicle 10.

[0047] As in Fig. 1, the vehicle 10 generally includes, in addition to the aforementioned steering system 24 and controller 34, a chassis 12, a body 14, front wheels 16, and rear wheels 18. The body 14 is disposed on the chassis 12 and substantially encloses the components of the vehicle 10. The body 14 and the chassis 12 may together form a frame. Wheels 16-18 are each rotatably connected to the chassis 12 near a corner of the body 14. In various embodiments, the wheels 16, 18 comprise a wheel assembly that also includes respective associated tires.

[0048] In various embodiments, the vehicle 10 is an autonomous vehicle, and the control system 100 and / or components thereof are integrated into the vehicle 10. The vehicle 10 is, for example, a vehicle that is automatically controlled to transport passengers from one location to another. The vehicle 10 is depicted as a passenger car in the illustrated embodiment, but it should be appreciated that any other vehicle, including motorcycles, trucks, sport utility vehicles (SUVs), recreational vehicles (RVs), watercraft, aircraft, and the like, may also be used.

[0049] As illustrated, the vehicle 10 generally also includes a propulsion system 20, a transmission system 22, a braking system 26, one or more user input devices 27, a sensor system 28, an actuator system 30, at least one data storage device 32, and a communication system 36. The propulsion system 20, in various embodiments, may include an internal combustion engine, an electric machine such as a traction motor, and / or a fuel cell propulsion system. The transmission system 22 is configured to transfer the power of the propulsion system 20 to the vehicle wheels 16 and 18 according to selectable gear ratios. According to various embodiments, the transmission system 22 may include a continuously variable automatic transmission, a continuously variable transmission, or other suitable transmissions.

[0050] The braking system 26 is configured to apply braking torque to the vehicle wheels 16 and 18. In various embodiments, the braking system 26 may include friction brakes, wire brakes, a regenerative braking system such as an electric machine, and / or other suitable braking systems.

[0051] The steering system 24 influences the position of the vehicle wheels 16 and / or 18. Although a steering wheel is shown for illustrative purposes, the steering system 24 may not include a steering wheel in some embodiments contemplated by the present disclosure.

[0052] The controller 34 includes a vehicle controller that is directly influenced based on the output of the neural network model 33. In an exemplary embodiment, a feedforward can be applied to an adjustment factor, which is the continuous output of the neural network models 33, to generate a control action for the desired torque or a similar action (for example, in the case of a continuous neural network model 33, the continuous APC / SPARK prediction values are outputs).

[0053] In various embodiments, one or more user input devices 27 receive inputs from one or more passengers (and the driver 11) of the vehicle 10. In various embodiments, the inputs include a desired travel destination for the vehicle 10. In certain embodiments, one or more input devices 27 include an interactive touchscreen in the vehicle 10. In certain embodiments, one or more input devices 27 include a speaker for receiving audio information from the passengers. In certain other embodiments, one or more input devices 27 may include one or more other types of devices and / or may be coupled to a user device (e.g., a smartphone and / or other electronic devices) of the passengers.

[0054] The sensor system 28 includes one or more sensors 40a-40n that detect observable conditions of the external environment and / or the internal environment of the vehicle 10. The sensors 40a-40n include, among others, radars, lidars, global positioning systems, optical cameras, thermal cameras, ultrasonic sensors, inertial measurement devices, and / or other sensors.

[0055] The actuator system 30 includes one or more actuators 42a-42n that control one or more vehicle functions, such as, but not limited to, the canister purge system 31, the intake system 38, the drive system 20, the transmission system 22, the steering system 24, and the braking system 26. In various embodiments, the vehicle 10 may also include interior and / or exterior vehicle features that are Fig. 1 are not shown, such as various doors, a trunk, and cabin features such as air, music, lighting, touchscreen display components (for example, those used in conjunction with navigation systems), and the like.

[0056] The data storage device 32 stores data for use in automatically controlling the vehicle 10, including storing data from a DNN created by the RL to predict driver behavior for vehicle control. In various embodiments, the data storage device 32 stores a machine learning model of a DNN and other data models created by the RL. The model created by the RL can be used for a DNN behavior prediction model or a model created by the RL. In an exemplary embodiment, no separate training is required for the DNN; instead, the DNN behavior prediction model (i.e., the DNN prediction model) is implemented with a set of learned features.In various embodiments, the neural network 33 (i.e., the DNN behavior prediction model) may be created by RL or trained by a supervised learning technique from a remote system and transmitted to the vehicle 10 (wirelessly and / or wired) or provided and stored in the data storage device 32. The DNN behavior prediction model may also be trained by supervised or unsupervised learning based on input vehicle data of a host vehicle operation and / or collected data about a host vehicle operating environment.

[0057] The data storage device 32 is not limited to control data, as other data may also be stored in the data storage device 32. For example, route information may also be stored in the data storage device 32, i.e., a series of road segments (geographically linked to one or more of the defined maps) that together define a route the user can take to get from a starting location (e.g., the user's current location) to a destination. As can be appreciated, the data storage device 32 may be part of the controller 34, separate from the controller 34, or part of the controller 34 and part of a separate system.

[0058] The controller 34 implements the logic model created by RL or for the DNN based on the DNN behavior model trained with a set of values and includes at least one processor 44 and a computer-readable storage device or medium 46. The processor 44 may be any custom or off-the-shelf processor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processor among multiple processors connected to the controller 34, a semiconductor-based microprocessor (in the form of a microchip or chipset), any combination thereof, or generally any device for executing instructions. The computer-readable storage device or media 46 may include volatile and non-volatile memory, for example, read-only memory (ROM), random access memory (RAM), and keep-alive memory (KAM).KAM is a persistent or non-volatile memory that can be used to store various operating variables while the processor 44 is off. The computer-readable storage device(s) 46 can be implemented using any number of known storage devices such as PROMs (programmable read-only memory), EPROMs (electrical PROM), EEPROMs (electrically erasable PROM), flash memory, or other electrical, magnetic, optical, or combination storage devices capable of storing data, some of which represent executable instructions used by the controller 34 in controlling the vehicle 10.

[0059] The instructions may comprise one or more separate programs, each containing an ordered list of executable instructions for implementing logical functions. The instructions, when executed by processor 44, receive and process signals from sensor system 28, perform logic, calculations, methods, and / or algorithms to automatically control the components of vehicle 10, and generate control signals that are transmitted to actuator system 30 to automatically control the components of vehicle 10 based on the logic, calculations, methods, and / or algorithms. Although in Fig. 1 only one controller 34 is shown, embodiments of the vehicle 10 may include any number of controllers 34 that communicate via any suitable communication medium or combination of communication media and that cooperate to process the sensor signals, perform logic, calculations, methods and / or algorithms, and generate control signals to automatically control features of the vehicle 10.

[0060] The communication system 36 is configured to wirelessly transmit information to and from other units 48, such as other vehicles (“V2V” communication), the infrastructure (“V2I” communication), remote transportation systems, and / or user devices (described in more detail with respect to Fig. 2). In an exemplary embodiment, the communication system 36 is a wireless communication system configured to communicate over a wireless local area network (WLAN) using IEEE 802.11 standards or using cellular data communication. However, additional or alternative communication methods, such as a dedicated short-range communication channel (DSRC), are also contemplated within the scope of this disclosure. DSRC channels refer to short- to medium-range, one-way or two-way wireless communication channels specifically designed for use in motor vehicles, as well as a set of protocols and standards.

[0061] In various embodiments, communication system 36 is used for communication between controller 34, including data related to a projected future path of vehicle 10, including projected future steering instructions. In various embodiments, communication system 36 may also facilitate communication between steering control system 84 and / or other systems and / or devices.

[0062] In certain embodiments, the communication system 36 is further configured for communication between the sensor system 28, the input device 27, the actuator system 30, one or more controllers (for example, the controller 34), and / or a plurality of other systems and / or devices. For example, the communication system 36 may include any combination of a Controller Area Network (CAN) bus and / or direct wiring between the sensor system 28, the actuator system 30, one or more controllers 34, and / or one or more other systems and / or devices. In various embodiments, the communication system 36 may include one or more transceivers for communication with one or more devices and / or systems of the vehicle 10, passenger devices (for example, the user device 54 of Fig. 2) and / or one or more sources of remote information (e.g. GPS data, traffic information, weather information, etc.).

[0063] In Fig. 2 illustrates an example environment 200 for using an enhanced cruise control system according to various embodiments. The example environment 200 shows a vehicle 210 equipped with a cruise control system and a road surface 220 with a gradient of Ø. In some example embodiments, the vehicle 210 may have transitioned from a gentle incline while performing a cruise control algorithm at a driver-defined set speed. To maintain the set speed, the cruise control system generates a corresponding engine torque request, which is coupled to the throttle controller or engine control unit (ECU) so that the set speed is maintained. As the vehicle 210 transitions onto the incline, the cruise control system traditionally must increase the engine torque request to maintain the set speed.When the vehicle reaches the top of a hill, the cruise control system must apply less engine torque and / or brakes to slow the vehicle's downhill momentum and thus maintain the set speed, further reducing fuel efficiency.

[0064] Cruise control is an electronic system that allows the driver to set a specific speed for their vehicle and then release their foot from the accelerator pedal. The system uses a servo mechanism that takes over the accelerator pedal and maintains a constant speed. Cruise control can be activated via controls on the steering wheel or via a user interface. Cruise control is useful for driving at a constant speed, especially on highways and fast roads with few curves or downhill sections. Cruise control can reduce driver fatigue and stress, prevent speeding, and reduce fuel consumption.

[0065] However, cruise control may not function safely and efficiently at night or in bad weather. Likewise, cruise control may result in lower fuel consumption on roads with frequent gradient changes, such as hilly areas.

[0066] An engine torque command is a signal sent from the driver's throttle body to the ECU. It tells the control unit how much torque the driver expects from the engine. The ECU then uses this signal to control fuel injection and ignition timing to achieve the desired torque. Engine torque is typically measured in Newton meters (Nm). For example, a torque command of 100 Nm means the driver wants the engine to produce 100 Nm of torque. Engine torque is a crucial factor in determining an engine's performance. If the torque command is too low, the engine will not produce enough power. If the desired torque is too high, the engine may overheat or even be damaged. The engine's torque command is also used to control the transmission. The transmission uses the torque command to determine how many gears to engage.For example, if the driver wants to accelerate quickly, the ECU sends a high torque command to the transmission, causing it to shift into a lower gear. The engine torque command is a complex signal influenced by several factors, including the driver's throttle position, engine speed, and engine load. The ECU uses a series of sensors to measure these factors and adjusts the torque command accordingly. Factors that can affect engine torque include the driver's throttle position, engine speed, engine load, and engine temperature. Engine torque is an important signal used to control engine performance.

[0067] A cruise control system is set to maintain a constant speed set by the user. This may cause the cruise control system to increase the engine torque request to maintain this speed when climbing hills and to brake when descending hills. To improve fuel efficiency when climbing hills, it is beneficial if the cruise control system can deviate from the set cruise speeds and maintain the torque request constant up to a certain speed limit set by the user. The system may first detect a road gradient in response to the current vehicle pitch angle to determine whether the vehicle is traveling uphill, level, or downhill.By reducing speed during uphill ascent, the cruise control system can reduce the vehicle's speed to the set speed while ascending, potentially avoiding deceleration during downhill descent. A new user input can be added along with a set of controls to establish a new minimum speed setting. The cruise control algorithm can also include an updated torque control strategy used during cruise control operation.

[0068] In some example embodiments, the cruise control algorithm receives a user-defined lower speed input indicating a minimum speed the user will allow the vehicle to travel before requesting an increase in torque. For example, the user may define a minimum speed 15 mph below the cruise control set speed. Alternatively, the user may define the minimum speed as a percentage of the cruise control set speed, for example, 85% of the cruise control set speed. The cruise control algorithm is then configured to monitor the vehicle pitch angle via a vehicle pitch angle sensor or the like. If the pitch angle sensor is positive, the algorithm determines that the requested torque will be held constant until the user input of the minimum speed is reached.If the pitch sensor is positive and the minimum speed is reached, the minimum speed can be maintained until the pitch sensor reports a limit. Once the pitch sensor remains stable, normal cruise control operation can be resumed based on the desired acceleration values. The reduced torque demand during an uphill climb promotes increased mileage through lower gas / electricity consumption.

[0069] Fig. Figure 3 is a diagram illustrating the components of a system 300 configured to operate using the cruise control system fuel efficiency algorithm in accordance with various embodiments described in the Fig. 1-2. The exemplary system 300 may include a user input 310, a processor 330, a vehicle controller 350, a pitch angle sensor 340, and a memory 260.

[0070] The example user input 310 may be a steering wheel-mounted touchpad, a center console touchpad, or other user interface for receiving user input 310 indicating cruise control activation, a set speed, and a minimum speed. Typically, a driver may activate the cruise control system and algorithm by initiating the cruise control system while driving at the desired set speed. The cruise control system then uses the vehicle's current speed at the time of activation as the set speed. Alternatively, the driver may press a resume button or the like, and the cruise control system will use a previously saved set speed as the current set speed.This may mean that the controller 330 generates engine torque requests so that the vehicle increases or decreases speed to transition from the current speed to the requested set speed.

[0071] The driver can enter a minimum speed via user input 310. The minimum speed is the lowest speed achievable while climbing an incline with a constant engine torque demand. For example, the driver can enter an exact speed, such as fifty-five miles per hour, a maximum speed reduction, such as ten miles per hour, or a maximum speed reduction percentage, such as fifteen percent. This minimum speed can be entered by the driver during cruise control system configuration before the vehicle is in motion. Alternatively, the driver can initiate the cruise control algorithm, for example, by activating the algorithm while traveling at the set speed and then being prompted to select a minimum speed via user input 310.The driver can then select the minimum speed by pressing an arrow button on the steering wheel, turning a job dial, pressing a level, or the like, until the minimum speed is displayed. The driver can then confirm the minimum speed with a separate button press or the like. This minimum speed can then be stored in memory 360 for use by the cruise control fuel efficiency algorithm. In some example embodiments, the cruise control fuel efficiency algorithm can be executed as part of a vehicle's fuel economy mode and automatically use the user-defined minimum speed or a default minimum speed stored in memory 360.

[0072] Processor 330 may be a component of a cruise control system, controller, vehicle control system, or the like. Processor 330 is configured to execute the cruise control fuel efficiency algorithm in response to driver activation of the cruise control system via user input 310 and the set speed. The minimum speed may be retrieved by processor 330 from memory 360. Processor 330 is configured to generate an engine torque request or similar control signal for coupling to vehicle controller 350. Vehicle controller 350 controls the vehicle throttle controller or the like so that the vehicle maintains the set speed. In some example embodiments, vehicle controller 350 may then transmit the current vehicle speed back to processor 330 for use by the cruise control algorithm.Next, processor 330 receives a vehicle pitch angle value from pitch angle sensor 340. If the vehicle pitch angle value indicates an incline, processor 330 may continue to couple the previous engine torque request to vehicle controller 350. Next, processor 350 receives the current vehicle speed from vehicle controller 350 and compares the current vehicle speed to the minimum speed. If the current vehicle speed is below the minimum speed, processor 330 may forward an updated engine torque request to vehicle controller 350 so that the vehicle maintains the minimum speed.Alternatively, if the current vehicle speed is below the minimum speed, the processor 330 may forward an updated engine torque request to the vehicle controller 350 so that the set speed is again achieved and the vehicle accelerates from the minimum speed to the set speed when climbing the incline.

[0073] In some example embodiments, in response to the vehicle pitch angle value indicating that the vehicle is climbing a grade, processor 330 may continue to couple the previous engine torque request to vehicle controller 350, and processor 330 may be further configured to turn off one or more heating and air conditioning components, such as an air conditioning compressor. Turning off the air conditioning compressor may advantageously reduce the engine torque required to maintain the set speed or may result in a loss of vehicle speed as the vehicle climbs the grade at the previous engine torque request.Turning off one or more heating and air conditioning components in response to the pitch angle value indicating that the vehicle is climbing an incline may result in more engine torque being delivered to the powertrain than during the level incline when the one or more heating and air conditioning components are turned on.

[0074] Pitch angle sensor 340 is configured to detect the current vehicle pitch angle and transmit data indicative of the current vehicle pitch angle to processor 330 and / or vehicle controller 350. A pitch angle sensor 340 may be part of a system, such as a six-axis inertial navigation system or an inertial measurement unit (IMU), that collects position, orientation, and velocity information using accelerometer and gyroscope sensors and can use this information to make predictions for the next position, orientation, and velocity using various algorithms.

[0075] Fig. 4 shows an exemplary flowchart illustrating a method 400 for using the system implemented using the cruise control fuel efficiency algorithm in accordance with various embodiments described in the Fig. 1-3. In some example embodiments, the example method is first operative to receive 405 a user input indicating a minimum speed. The minimum speed may be a percentage of the cruise control set speed or a maximum speed reduction, for example, fifteen miles per hour. The user, for example, a vehicle operator, may enter or select the minimum speed via a user interface, for example, an infotainment display, a dashboard display, or other user input.

[0076] Next, the method 410 activates a cruise control algorithm. The cruise control algorithm may be activated in response to a second user input at a user interface, for example, a button on the steering wheel. The cruise control algorithm next receives 412 the set speed. In some example embodiments, a set speed for the cruise control algorithm may be a current speed of the vehicle when the cruise control system is activated. Alternatively or additionally, the user may enter a set speed or increase or decrease the set speed via the user interface.

[0077] In response to the cruise control system being activated and the set speed being maintained, the method next generates 414 an engine torque request corresponding to the set speed. The engine torque request is an indicator of the engine torque required for the vehicle to travel at the set speed. Next, the method 415 detects a vehicle pitch angle. If the vehicle pitch angle is zero degrees or less, an engine torque request 417 is generated so that the vehicle maintains the set speed.

[0078] If the vehicle pitch angle is greater than zero degrees 420, indicating that the vehicle is climbing a hill or incline, the method maintains the previous engine torque request. In response to the transmission of the previous engine torque request, the method next receives 435 the current vehicle speed. The current vehicle speed may be received from a vehicle controller or another vehicle sensor or controller. The method next compares 440 the current vehicle speed to the minimum speed. If the current vehicle speed is not less than the minimum speed, the vehicle returns to sensing the vehicle pitch angle 415.

[0079] If the current vehicle speed is below the minimum speed, the method next increases the engine torque request and transmits this increased engine torque request to the vehicle controller. In some example embodiments, the increased engine torque request may cause the vehicle controller to maintain the minimum speed while the vehicle climbs the grade and the pitch angle remains greater than zero. Alternatively, the increased engine torque request may indicate an engine torque required to regain the set speed. After the increased torque request is transmitted to the vehicle controller, the method returns to detecting the vehicle pitch angle. 415.

[0080] It should be noted that the process of Fig. 1-4 may contain any number of additional or alternative tasks, that the Fig. The tasks shown in 1-4 do not have to be carried out in the order shown and that the process of Fig. 1-3 can be integrated into a more comprehensive procedure or process with additional functionality not described in detail here. In addition, one or more of the Fig. 1-3 in an embodiment of the Fig. 1-4 may be omitted as long as the intended overall functionality is retained.

Claims

[1] A method for controlling a vehicle speed, comprising: Receive, from a user interface, a set speed and a minimum speed; generating a first control signal indicative of a first engine torque request; controlling a vehicle to maintain the set speed in response to the first engine torque request; Detecting a vehicle pitch angle; Detecting the vehicle speed; and based on the vehicle pitch angle and vehicle speed: if the vehicle pitch angle is greater than zero degrees and the vehicle speed is greater than the minimum speed, generating a second control signal indicative of the first engine torque request and controlling the vehicle to maintain a first engine torque in response to the first engine torque request; or when the vehicle pitch angle is greater than zero degrees and the vehicle speed is less than the minimum speed, generating a third control signal indicative of a second engine torque request and controlling the vehicle to maintain the minimum speed in response to the second engine torque request. [2] The method of claim 1, wherein the set speed is received by the user interface in response to a user input. [3] The method of claim 1, wherein the set speed is determined in response to a vehicle speed during activation of a cruise control system. [4] The method of claim 1, wherein the vehicle speed is controlled by a vehicle controller in response to the first engine torque request and the second engine torque request. [5] The method of claim 1, wherein the minimum speed is received from the user interface in response to a user input. [6] The method of claim 1, wherein the minimum speed is a percentage of the set speed and is determined in response to a user input received prior to activation of a cruise control algorithm. [7] The method of claim 1, wherein the minimum speed is determined in response to a maximum allowable speed reduction determined in response to a user input received prior to activation of a cruise control algorithm. [8] A method according to claim 1, wherein the minimum speed is a default value stored in a memory when the vehicle is put into operation. [9] The method of claim 1 further comprising deactivating an air conditioning compressor in response to the vehicle pitch angle being greater than zero degrees and the vehicle speed being greater than the minimum speed and less than the set speed. [10] Cruise control system, comprising: a user interface for receiving a set speed and a minimum speed; a pitch angle sensor for detecting a vehicle pitch angle; a speed sensor for detecting a vehicle speed; a processor; and a vehicle control unit for controlling the vehicle speed; wherein the cruise control system is configured to carry out the method according to any one of the preceding claims.

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