The present invention relates to vehicle control in general, and more particularly to vehicle control and driver-vehicle interfaces.
The advent of “smart” vehicles and infrastructure promises to automate much of the task of driving. However, it will be some time before the human driver may be completely done away with. In the interim, there is a need to balance increasing vehicle autonomy with the level of control and responsibility that drivers maintain for their vehicles' actions.
The present invention is intended to improve vehicle operation without wresting vehicle control from the hands of the operator. It does so using computer-assisted vehicle control whereby undesirable vehicle behavior, such as getting very close to another vehicle or obstacle, or colliding with it, is made more difficult to accomplish by dynamically limiting or changing the effect of one or more vehicle controls. The driver is preferably kept aware of such dynamic changes through signals, such as via haptic feedback through the affected controls. Automated vehicle control is preferably provided such that:
The automated vehicle control system of the present invention preferably mediates between the vehicle controls, through which the driver conveys his/her intents regarding the vehicle's behavior, and the underlying vehicle systems that directly affect vehicle behavior (e.g., acceleration).
In one aspect of the present invention a vehicle control system is provided including a vehicle, and a vehicle controller configured to receive information regarding the vehicle and its environment, receive vehicle control input via at least one vehicle control of the vehicle, apply control logic predefined for the received vehicle control input and the information, thereby determining at least one aspect of the vehicle to control and how to control the aspect, and send a control directive to at least one vehicle subsystem to carry out the determined control of the aspect, where when the vehicle is in a first operational state the vehicle controller allows the vehicle control input to control the at least one vehicle subsystem directly related to the vehicle control input without modification by the vehicle controller, and where when the vehicle is in a second operational state the vehicle controller uses the vehicle control input to determine a vehicle objective and sends the control directive to any of the vehicle subsystems in order to achieve the vehicle objective.
The present invention in embodiments thereof will be understood and appreciated more fully from the following detailed description taken in conjunction with the appended drawings in which:
Reference is now made to
Vehicle controller 102 also preferably provides haptic feedback to the driver through vehicle controls 108. Such feedback is preferably produced when the vehicle control input provided by the driver via vehicle controls 108 differs by a predefined measure from the action vehicle controller 102 actually takes when controlling vehicle 100 after applying control logic 110 to the vehicle control input. For example, if the accelerator pedal is depressed to indicate a desired rate of acceleration and/or speed, but the acceleration rate or speed it would normally entail exceeds a safety margin, vehicle controller 102 may decide to accelerate the vehicle at a slower rate or not at all and/or achieve a lower speed than the driver requests. Vehicle controller 102 preferably controls the accelerator pedal using conventional techniques to resist the driver's pressure on the pedal, conveying to the driver that the driver's command has been overridden.
Reference is now made to
Vehicle controller 102 preferably provides haptic feedback to the driver through vehicle controls 108, such as by causing the accelerator to vibrate upon entering and leaving the trailing zone in order to indicate to the driver that the behavior of the accelerator has been changed as described above, and/or by providing varying degrees of resistance in proportion to the degree with which the driver depresses the accelerator while vehicle 200 is within the trailing zone.
The driver may indicate his desire to leave the trailing zone mode by performing an override action, such as when the driver activates the turn signal when changing lanes, in which case vehicle controller 102 preferably reverts to normal zone mode, allowing the driver to directly control fuel flow.
Distances between vehicles moving at similar speeds, and thus the boundaries of the various zones described above, may be stated in terms of travel time. For example, the trailing zone (TZ) boundary farthest from vehicle 202 may be set at a distance from vehicle 202 such that vehicle 200 would take dTZ seconds to traverse the TZ at its present speed. The forbidden zone (FZ) boundary may similarly be set for a traversal time of dFZ, where dTZ>dFZ. The boundaries for TZ are also preferably determined based on a predefined minimum stopping distance, being the distance in which stopping without the assistance of vehicle controller 102 is difficult, such as where the distance to vehicle 202 is too short for the driver of vehicle 200 to notice and brake his vehicle in time, whereas the minimum distance from vehicle 202 would be safe if vehicle controller 102 were configured to automatically initiate the braking action. The extent of the FZ is typically set such that even automatic braking within the FZ would be unsafe. Typical values are dTZ=2 secs. and dFZ=0.5 secs.
Vehicle controller 102 may maintain vehicle 200 at a fixed travel-time distance from vehicle 202 by adjusting its speed to follow the speed changes of vehicle 202. Alternatively, this may be performed asymmetrically, such as where vehicle 200 slows down as much as vehicle 202 does, but where vehicle 200 only accelerates to a limited degree as a result of vehicle 202 accelerating, such as where vehicle 200 accelerates to the speed with which vehicle 200 was traveling just before it last entered the TZ plus some fixed amount, say 25 km/h, or percentage of its present cruising speed, such as 15%, or some limit imposed by other modes in effect, such as curve following. For example, a fixed addition may be used in low speed, stop-and-go traffic below a predefined speed threshold, whereas a percentage may be used when cruising at higher speeds above a predefined speed threshold. In this manner vehicle 200 may be prevented from being “pulled ahead” by a fast vehicle passing vehicle 200 and planting itself in front of vehicle 200.
Vehicle controller 102 may be configured to allow vehicle 200 to enter the TZ only when it is clear the driver does not intend to pass vehicle 202. The driver may indicate his intention to pass vehicle 202 by using the turn signal, by depressing the accelerator pedal into an override position, or by activating a special control dedicated to this purpose, among other possibilities, whereupon vehicle 200 does not slow unless and until the FZ is reached.
Vehicle controller 102 may be configured to control vehicle 200 as it approaches stationary objects, where vehicle 200 would slow to a complete stop to avoiding hitting a stationary object while allowing the driver to come close to the object by depressing the accelerator, or even to touch the object by performing an override action. In this case the width of the FZ may be set to zero or eliminated altogether. This may be employed during parallel parking, where the driver may freely depress the accelerator and depend on vehicle controller 102 to slow and/or stop vehicle 200 to avoid hitting other parked cars. When moving in reverse, a vehicle behind vehicle 200 is considered to be the vehicle being “trailed” as described above.
The present invention is believed to improve the driving experience by:
Improving safety, by automatically performing a vehicle control action quicker than a human driver could;
Making driving easier in general, by relieving the driver of the necessity to make conscious decisions and physical efforts to adjust the vehicle's motion to rapidly changing traffic situations;
Providing faster automatic response to advance other goals, such as improving traffic flow; and
Maintaining ultimate driver control and responsibility for the vehicle.
It is appreciated that the present invention may be applied to stop-and-go traffic where the speeds of the vehicles involved are relatively slow. A vehicle operating in this mode may stop completely when the vehicle it is tracking stops, and may start moving again when the tracked vehicle starts to move. Currently available vehicle control systems, such as Adaptive Cruise Control, are specifically disabled at low speeds to prevent the vehicle from suddenly moving forward and injuring pedestrians that may have stepped in front of the stopped vehicle. The present invention is believed to solve this problem by allowing the driver to actively and constantly control the distance between the driver's vehicle and the vehicle immediately ahead. Were a driver, using the present invention, to instinctively remove his foot from the accelerator to avoid hitting a pedestrian, the vehicle would leave the trailing mode, and the vehicle would no longer automatically accelerate to keep up with the vehicle ahead.
It is further appreciated that the present invention may be applied while the driver is parking a vehicle. Normally, parallel parking between closely parked cars requires several back and forth maneuvers. Although self-parking vehicle systems are currently available, they do not give drivers control during the process. For example, the driver may wish to park closer to the curb in a narrow street to minimize obstruction of traffic, or conversely, further from a wall to allow easy access to the doors on the passenger side. Moreover, a driver may sometimes wish to stay clear of an obstacle thah an automated system may not notice, such as a puddle. The present invention may be applied during parking to avoid the curb, other parked cars, objects such as parking meters, etc., and haptically indicate to the driver when these obstacles are being approached too closely. In an exemplary scenario, a driver stops his vehicle next to a parking space and instructs the system, such as via a dedicated switch, to enter a parking mode of operation. Vehicle motion is then modified in two respects:
In all other respects the driver continues to control the vehicle normally, controlling forward and reverse motion of the vehicle using the gear control, and the distance from obstacles in the vehicle's path using the gas pedal. The vehicle may employ vehicle control as described hereinabove regarding the stop-and-go traffic.
Unless stopped by the driver, the vehicle will move as far as it can in the direction indicated, automatically turning the tires leftward and rightward as needed, ending in a parallel position within the parking space that is closer to the curb by an amount determined by the degree of steering wheel rotation. In order to move the vehicle laterally, all the driver needs to do is to switch from forward to reverse and back, while constantly keeping the steering wheel turned in the direction of the desired lateral movement. The lateral displacement component is preferably proportional to the degree of steering wheel rotation from a home position. As the driver moves the steering wheel back to its home position, the vehicle will take increasingly smaller lateral steps, and will halt when the wheel returns to its center position. The lateral component of each forward and backward movement may be limited by a predefined maximum angle of attack, or one that is determined by a predefined function given measured distances to the curb and/or other obstacles bounding the parking space. The steering wheel preferably haptically conveys to the driver when the degree of rotation of the steering wheel would result in an angle of attack of each lateral movement that is greater than the maximum angle of attack. Thus, the driver may select any desired angle of attack up to the maximum angle of attack, or may override the maximum angle using an override mechanism such as is described hereinabove.
The driver may control the distance of the vehicle from obstacles in its path using the gas pedal as described hereinabove, while allowing for driver override.
It is appreciated that one or more of the steps of any of the methods described herein may be omitted or carried out in a different order than that shown, without departing from the true spirit and scope of the invention.
While the methods and apparatus disclosed herein may or may not have been described with reference to specific computer hardware or software, it is appreciated that the methods and apparatus described herein may be readily implemented in computer hardware or software using conventional techniques.
While the present invention has been described with reference to one or more specific embodiments, the description is intended to be illustrative of the invention as a whole and is not to be construed as limiting the invention to the embodiments shown. It is appreciated that various modifications may occur to those skilled in the art that, while not specifically shown herein, are nevertheless within the true spirit and scope of the invention.