Patent Application
20150057906
1. Technical Field
The present disclosure relates to the field of vehicle energy management. In particular, to a system and method for vehicle energy management.
2. Related Art
Many mechanisms have been developed to help optimize energy consumption in vehicles. However, some aspects of vehicle energy consumption continue to be significantly affected by driver related factors such as driving style (e.g heavy acceleration and sudden braking). Drivers sometimes choose less than optimal modes of operation of the vehicle based on a lack of information about the driving context (e.g. up coming traffic congestion and road topology ahead).
Existing systems that give fuel economy indications or driver suggestions are typically based on past and current vehicle state and/or operating conditions. For example, for naturally aspirated internal combustion engines the intake manifold vacuum can be used to infer efficient engine operation and can be displayed on a gauge. Also, instantaneous or average fuel consumption can be computed and displayed. In hybrid and electric vehicles instantaneous energy consumption can be displayed. These solutions are limited in their beneficial impact due to being retrospective in nature—that is, being based on past and current vehicle state and/or operating conditions.
The system and method may be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the disclosure. Moreover, in the figures, like referenced numerals designate corresponding parts throughout the different views.
Other systems, methods, features and advantages will be, or will become, apparent to one with skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included with this description and be protected by the following claims.
A system and method for vehicle energy management are described that take driving context into account to derive suggested vehicle control inputs to reduce energy consumption. Driving context may be based on information including, for example, traffic congestion and/or flow information for a travelled route, road topology information (e.g. changes of elevation and/or grade ahead), traffic controls (e.g. traffic lights, stop signs), weather conditions, vehicle characteristics (e.g. re-generative braking equipped, type of transmission (e.g. continuously variable or stepped gear ratio), vehicle energy consumption profile) and other types of driving context information. The driving context may be used to derive suggested control inputs (e.g. acceleration, deceleration or braking) to reduce energy consumption. The suggested control inputs may, for example, be expressed as: a suggested road speed, suggested gear selection, rate of acceleration or rate of deceleration.
The suggested control inputs may be displayed to the driver as a suggested speed indicator, an acceleration or deceleration magnitude indicator, or other similar displays. Alternatively or in addition, the suggested control inputs may be provided to a cruise control mechanism (including adaptive cruise control system) and/or powertrain management system.
The input signals and/or data related to driving-context received by the driving-context input module 102 may be received from systems such as, for example, the positioning system 118, the traffic status system 120, the navigation system 124, the cruise control system 116, the power train management system 114 and the VDI 122. The input signals and/or data related to driving-context may include, for example, vehicle speed, vehicle direction of travel (e.g. bearing), vehicle location (e.g. longitude and latitude), anticipated route (e.g. a navigation system planned route), cruise control status (e.g. active/inactive, speed setting), live traffic information (e.g. traffic management channel (TMC) information), topology and/or terrain information, and other similar information that may be related to driving-context. Input signals and/or data related to driving-context received from the VDI 122 may include inputs and/or selections made by the driver 132.
The off-vehicle sources may provide signals and/or data related to, for example, traffic information, topology information, traffic controls information, weather information and other similar information that may be pertinent to vehicle energy management. The traffic information may include, for example, crowd-sourced traffic information, real-time traffic information, sensor-based traffic information, time-of-day/day-of-week traffic profile information and other similar traffic information. The traffic controls information may include, for example, placement, type, cycle-time/schedule and operational state of traffic controls such as traffic lights, stop signs, yield signs, speed limit zones and other similar traffic controls. Topology information may include, for example, road layout, road elevation and road grade (i.e. slope) data, topography, road surface type (e.g. paved, gravel, dirt), road classification (e.g. single lane, multi-lane, limited access, level intersections, overpass) and other similar topology information.
The retrievable information stored in the vehicle characteristics repository 104 may include vehicle characteristics such as, for example, powertrain type (e.g. internal combustion engine, hybrid, electric), whether the vehicle is re-generative braking equipped, type of transmission (e.g. continuously variable or stepped gear ratio), vehicle energy consumption profile (e.g. fuel consumption versus engine speed, road speed or load) and other similar vehicle characteristics. The retrievable information may also include vehicle status information such as, for example, powertrain operating temperature, hybrid operating mode (e.g. electric, engine or combined propulsion), cruise control engaged, current road speed, throttle position and other similar vehicle status information.
The control input generation module 106 may use inputs and data from the driving-context input module 102 and the vehicle characteristics repository 104 to derive suggested control inputs. The derived suggested control inputs are directed to mitigating energy consumption by the vehicle 130. The control input generation module 106 uses the signals and data received via the driving-context input module 102 and/or the data retrieved from the vehicle characteristics repository 104 to generate a projected (a.k.a. anticipated) near-term future driving context. This may include using topographic information to determine, for example, that a current up-hill grade will end in 500 meters and then will be followed by a 2% down-hill grade for an additional 800 meters. In another example the projected near-term future driving context may include a stop sign ahead or an increase in speed limit ahead. In a further example when the vehicle is approaching a traffic light that is beyond the driver's line of sight (e.g. where the road turns ahead or there is an elevation change), the system 100 may be able to project based on, for example, known traffic light cycle-time and/or time-of-day that the traffic light will be signaling ‘stop’ (e.g. indicating ‘red’) when the vehicle 130 arrives and therefore may generate a suggested control input that forgoes further acceleration and/or recommends coasting as the vehicle approaches the traffic light. Projecting the driving context may include the use of extrapolation, interpolation or other projection or prediction techniques. In another example, when driving from a starting point A to an end point B and traffic information (e.g. crowd-sourced traffic information) indicates that there is congestion at a point between A and B, the system 100 may derive a suggested control input that would result in the vehicle 130 travelling at a speed below a speed-limit for the route (or speed-limits for sections of the route) in order to mitigate slowing or stopping due to the congestion or in hopes that the congestion will dissipate before the vehicle 130 arrives at the point of congestion thereby mitigating energy consumption. The foregoing examples are only illustrative in nature and are in no way meant to be limiting.
The control input generation module 108 may use the projected near-term future driving context to derive one or more suggested control inputs. The suggested control inputs may include, for example, accelerate (optionally including a magnitude indication), decelerate (optionally including a magnitude indication), maintain a constant speed, prepare to brake, brake (optionally including a magnitude indication) and other similar suggested control inputs.
The suggested control inputs may be displayed, or otherwise presented, through the VDI 122 to provide the driver 132 with an indication (a.k.a. hints or cues) as to what vehicle control inputs will mitigate energy consumption by the vehicle 130 based on the projected near-term future driving context. Alternatively, or in addition, the suggested control inputs may be provided to the cruise control system 116. The cruise control system 116, when activated, may for example use the suggested control inputs to adjust a speed setting upwardly or downwardly in accordance with the suggested control inputs or may disengage the cruise control system 116. Further alternatively, or in addition, the suggested control inputs may be provided to the powertrain management system 114. The powertrain management system 114 may for example use the suggested control inputs to adapt, configure or operate one or more components of the powertrain (a.k.a. drivetrain) in order to mitigate power consumption.
Referring again to
The processor 110 may comprise a single processor or multiple processors that may be disposed on a single chip, on multiple devices or distributed over more that one system. The processor 110 may be hardware that executes computer executable instructions or computer code embodied in the memory 128 or in other memory to perform one or more features of the system 100. The processor 110 may include a general purpose processor, a central processing unit (CPU), a graphics processing unit (GPU), an application specific integrated circuit (ASIC), a digital signal processor (DSP), a field programmable gate array (FPGA), a digital circuit, an analog circuit, a microcontroller, any other type of processor, or any combination thereof.
The memory 128 may comprise a device for storing and retrieving data, processor executable instructions, or any combination thereof. The memory 114 may include non-volatile and/or volatile memory, such as a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), or a flash memory. The memory 114 may comprise a single device or multiple devices that may be disposed on one or more dedicated memory devices or on a processor or other similar device. Alternatively or in addition, the memory 114 may include an optical, magnetic (hard-drive) or any other form of data storage device.
The memory 114 may store computer code, such as instructions to implement the driving-context input module 102, the control input generation module 106, the vehicle characteristics repository 104 and the control output module 108 as described herein. The computer code may include instructions executable with the processor 110. The computer code may be written in any computer language, such as C, C++, assembly language, channel program code, and/or any combination of computer languages. The memory 114 may store information in data structures including, for example, all or a portion of the data related to driving-context, the vehicle characteristics, vehicle status information, near-term future driving context and the suggested control inputs.
The I/O interface 112 may be used to connect devices such as, for example, the positioning system 118, the traffic status system 120, the navigation system 124, the cruise control system 116, the power train management system 114, the VDI 122, the data communication system 126 and to other components of the system 100.
All of the disclosure, regardless of the particular implementation described, is exemplary in nature, rather than limiting. The system 100 may include more, fewer, or different components than those illustrated in
The functions, acts or tasks illustrated in the figures or described may be executed in response to one or more sets of logic or instructions stored in or on computer readable media. The functions, acts or tasks are independent of the particular type of instructions set, storage media, processor or processing strategy and may be performed by software, hardware, integrated circuits, firmware, micro code and the like, operating alone or in combination. Likewise, processing strategies may include multiprocessing, multitasking, parallel processing, distributed processing, and/or any other type of processing. In one embodiment, the instructions are stored on a removable media device for reading by local or remote systems. In other embodiments, the logic or instructions are stored in a remote location for transfer through a computer network or over telephone lines. In yet other embodiments, the logic or instructions may be stored within a given computer such as, for example, a CPU.
While various embodiments of the system and method for vehicle energy management have been described, it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible within the scope of the present disclosure. Accordingly, the system and method are not to be restricted except in light of the attached claims and their equivalents.
