WO2015176804A1

WO2015176804A1 - System for assisting in driving a vehicle

Info

Publication number: WO2015176804A1
Application number: PCT/EP2015/000983
Authority: WO
Inventors: Michele ROLLI
Original assignee: Rolli Michele
Priority date: 2014-05-21
Filing date: 2015-05-13
Publication date: 2015-11-26

Abstract

Method for assisting in driving a vehicle comprising the following steps: - detecting the vehicle position by means of satellite signals; - acquiring the geometric constraints of the road track where the vehicle is moving along; - detecting the current conditions of motion of the vehicle; - processing the data of current conditions of motion of the vehicle to identify the current potentials of maneuverability of the vehicle; - checking the compatibility, using the acquired data, between the geometric constraints of the road track where the vehicle is moving along and its current potentials of maneuverability; - displaying of projected light signalling upon the stretch of road surface ahead of the vehicle, as a function of said compatibility check.

Description

TITLE

System for Assisting in Driving a Vehicle.

DESCRIPTION

The present invention concerns an improved method for assisting in driving a vehicle according to claim 1, and an apparatus according to claim 13, using said method.

BACKGROUND ART

Driver assisting systems are known wherein their hosting vehicles are detected to be exceeding safe cruise conditions and the driver is assisted in controlling his/her vehicle and in making decisions on the correct speed and trajectory. Various types of assistance systems, such as optical and acoustic ones, are already used to provide drivers with information and warnings, particularly in cases of rapid approach to road bends and obstacles, and alert them on locations where potential hazards may occur. The visual representation of significant information, which is conveyed to drivers by means of dashboard screens and Head-Up Displays (HUD), is also known. In said systems a virtual image of the roadway ahead in the vicinity of the vehicle is synthesized and rendered. Document EP 2 618 108 A1 discloses a driving assisting system comprising means of calculation and representation. Said means of representation are adapted to provide information on a screen or a Head-Up Display (HUD). According to gathered information, the system represents the estimated impending path of the vehicle. The driver is not always able to pay attention to the screen, and it may be even hazardous to divert his/her attention and eye-focus from the roadway to check the virtual represented path of his/her vehicle. Also the HUD is not appear to be the best means for displaying information with due clarity, immediacy, and proper 3D rendering. Particularly in low visibility and emergency circumstances, it is necessary that driver's eyes be focused on his/her actual route in front. Furthermore, the vehicle's future path, which as an additional value, and which could provide visible safety advantages, is not evident to other drivers in the proximity. The incidence of underestimated distances and high speeds still remains today a critical source of car accidents, so the object of the present invention is to define a method of driving assistance which would allow to mitigate the above said drawbacks and risks. The present method is disclosed to assist drivers by improving their spatial and situational awareness, providing them with timely warnings from the very roadway they are driving along. Visual warning signalling is instantaneously forwarded to the driver, allowing him/her to anticipate the latency or the approaching of risks related to the dynamic response of the vehicle, both in longitudinal and lateral directions. The main implementation of said signalling is specifically meant to keep the driver's attention on the route, focusing it by projecting the said light signals onto the road surface in front of the vehicle. This provides strong instinctive connotations for immediate fruition and reaction, as well as the additional advantage of generating signalling upon a surface that is independent of the driver's point of view. The present method's aim is to identify and better highlight a set of conditions where driving safety may be jeopardized, due to the circumstances arising along the route. A better and farther predictive discernibility is herewith achieved too, and an optimal logic is proposed by a particular exemplary embodiment, as exposed below. The above-said signalling type, aimed at night and twilight uses (i.e. when perception of distances and speeds is weaker), can be integrated in some embodiments with additional forms of traditional signallings, such as representation on the navigator screen, speedometer, and through audible alerts or callouts. Advantageous executions come from the following description of a number of exemplary achievements and embodiments and from the relevant claims in a nonrestrictive way.

TECHNICAL FIELD

The present invention relates, but is not limited, to the automotive industry in general, primarily to passenger transportation, freight transport on trucks (including articulated), and motorcycles. Rescue and Police vehicles can substantially benefit from what is herewith proposed, due to the unusual and demanding operations they are required to perform. More potential implementations can be envisaged for rail vehicles, underground trains, forklifts, airport handling and pushback maneuvers. Even the upcoming introduction of driverless vehicles does not exclude the exploitation of the present method since it allows drivers in the vicinity to anticipate what the kinematic behavior of the driverless vehicle will be. Particular attention is also paid to aircraft operations during takeoff and landing phases, and ground taxi operations in aerodromes, as later exposed. In consideration of the wider scope of scenarios, the present description is mainly focused on the automotive field.

DISCLOSURE OF INVENTION

According to the present invention, a system for assisting the driving of a vehicle is provided, wherein said system comprises the method and the means using said method, which are adapted to determine and display to the driver visual signallings aimed at the above recalled safety objects. Said vehicle hosting said system. Said method is made up of the three steps of acquiring, processing, and displaying of said signalling, as is more extensively expounded below. In conjunction with detecting vehicle position by means of a device receiving satellite signals (Global Navigation Satellite System - GNSS), said acquiring step is in charge of detecting the environmental information relevant for identifying the geometric constraints of the road track ahead of the vehicle. According to some embodiments, the definition of the geometric constraints is focused on a limited stretch of road ahead of the vehicle, within which suitable quantitative assessments are accomplished. According to some embodiments, the track geometry definition is implemented by means of a map where the vehicle, as localized by said device receiving satellite signals, is moving along. According to some embodiments, said satellite signal receiver is further refined with augmented GNSS capability aimed at improving the receiver performances of localization. According to some embodiments, "dead reckoning" techniques support and refine the localization performances. According to some further embodiments, optical or other data from environment sensing units perform or integrate the recognition of the environmental constraints information in order either to define the geometry of the stretch of road, and/or to detect unexpected foreign objects and/or obstacles able to affect the safe motion of the vehicle. The subsequent processing step provides for the whole activity of investigation about safety conditions and the determination of alerts and signallings resulting from the compatibility check between the geometric constraints of the stretch of road ahead, as received from said acquiring step, and the quantitative estimate of manoeuvrability potentials of the vehicle under current conditions of motion. According to some embodiments, the quantitative assessments are aimed at checking and evaluating which the extent is of said compatibility between the potentials of maneuverability provided by the vehicle at its current conditions of motion and the geometric constraints from the road track, as available from said acquiring step. In this way a level of risk can also be assigned to said alerting and signalling by estimating to which extent the safety conditions are being affected. According to some embodiments said compatibility check between the potentials of maneuverability of the vehicle and the geometric constraints from the road track comprise the determination of one minimum turning radius and/or available lateral excursion, and/or one longitudinal stopping distance. According to some further embodiments, said processing step is adapted to determine an estimated vehicle path, suitable to be evaluated in terms of risk level and readily displayed by projecting means upon the roadway surface. Finally, said display step comprises visual signalling by a light source, possibly a vivid laser, projecting light beams and figurations onto the stretch of road surface ahead of the vehicle as a result of the compatibility checks and/or risk level determined by said processing step. According to some embodiments, said visual signalling is a straightforward representation of the vehicle's estimated path upon the stretch of road, and/or its stopping distance, as determined by said processing step. The present invention will now be described more fully with reference to the accompanying drawings, in which example embodiments are shown. However, this invention should not be construed as limited to the embodiments set forth herein. Disclosed features of example embodiments may be combined as readily understood by one of ordinary skill in the art to which this invention belongs. Like numbers refer to like elements throughout. Well-known functions or constructions will not necessarily be described in detail for brevity and/or clarity.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and details of some implementing ways of the invention preferred and not limited to what is herein exposed will be specified with clarity from now on in the following chapters and with reference to the attached drawings, in which:

Figure 1 illustrates a flow chart according to some embodiments of the present invention;

Figure 2 illustrates a block diagram of an apparatus according to some embodiments of the present invention; Figure 3 illustrates a block diagram more detailed than in Figure 2, and has been introduced for clarity purposes in order to convey all devices in Figure 6 towards their respective functional areas: acquiring, processing, displaying, as per Figures 1 and 2.

Figures 4A 4B and 4C illustrate a stretch of road showing some exemplary signalling of the estimated vehicle path according to some embodiments;

Figure 5 illustrates a stylized representation of a vehicle dashboard according to some embodiments, where known means of acoustic warning signals and on-screen reproduction inside the car (e.g. the same as a GPS navigator) are complementary of what is projected outside, and for daylight driving.

Figure 6 illustrates a scheme of an apparatus using methods and logics according to some embodiments of the present invention;

Figures 7A and 7B plot the quantitative assessment of the risk level associated with current cruise and speed conditions according to some embodiments of the present invention. DESCRIPTION OF THE DRAWINGS

The exemplary embodiment in Figure 1 depicts one method

(100) of implementing the predictive path signalling according to the present invention.

Said method (100) consists of the three core steps of: acquisition (101) of all the constraints from the surrounding environment and vehicle position, processing (102) and evaluating the safety conditions for the vehicle motion, and emitting (103), i.e. the displaying of alerts related to such conditions in the main form of visual signalling towards a user interface.

The block diagram in Figure 2 represents an apparatus (200) implementing and utilizing said method (100), comprising all its essential composing devices (201), (202) and (203) as they might outline an embodiment of the present invention. In said representation in Figure 2 it has been chosen to arrange composing block devices (201), (202), and (203) following the same sequence of steps (101), (102) and (103) of method (100), as they execute the corresponding functions, without limiting to the present the only feasible architecture. The Block device (201) implements the step

(101) of detection of vehicle position and the acquisition of road layout (11), leading to the entire geometric constraints within which system calculations (102) will be focused. The vehicle position information is primarily determined by a GNSS satellite system and, according to some embodiments, the localization performance is enhanced in terms of accuracy by GNSS "augmented" features. According to some embodiments, relying also on the road geometry from a more precise 3D map, said block device 201 is adapted to return the stretch of road exactly ahead of the vehicle position, as detected by the GNSS. According to some embodiments, the localization performance is refined by car chassis sensors in order to obtain more and better position fixes, after integration by methods already known such as "Dead Reckoning". According to some embodiments, information from environment sensing units, also comprising optical data from a camera, and/or infra-red camera, and/or radar, and/or laser systems, and/or sonar systems, and/or LIDAR (Light Detecting and Ranging), are merged into the above detection step in order to optimize and integrate the definition of the road stretch. Moreover, the above said environment sensing units can be adapted to detect and identify other vehicles and/or unexpected foreign obstacles which could possibly be affecting the estimated safe path. Block device (202) is in charge of processing and evaluating the current safety conditions of driving. Said block (202) gathers the geometric constraints of the route where the vehicle is moving along with reference to its own position from block (201), and provides for the two internal sub-steps of processing (202-1) the current conditions of motion of the vehicle in order to estimate its current potentials of maneuverability and, in the light of that, of checking (202-2) the compatibility between the geometric constraints (201) of the road track and said estimated potentials of maneuverability by sub-block (202- 1). According to some embodiments, block (202) is also adapted to be supplied with external environment conditions such as the contamination status of road pavement by rain, ice or mud, presence of wind, and other inputs able to refine the estimate of said current potentials of maneuverability of the vehicle. According to some embodiments, block (202-1) simulates upon the track geometry its own estimate of the vehicle path (13). In all instances where, according to some embodiments, said prediction proves incompatible with the characteristics of the road and environment, said block (202- 2) evaluates the extent of such incompatibility and fixes a level of risk. Both the vehicle motion simulation and its level of risk are outputs of said block device (202). Block device (203) embodies the final section of the present apparatus (200) and is in charge of the interface to the driver and of the outputting of alert signallings to him/her. According to some embodiments, said block device (203) first graphically codifies the quantitative information received from said block device (202), converting it into what can be represented to the driver by the projector, and subsequently takes charge of checking the suitable overlap and consistency between what is projected (both from position and perspective standpoints) and the actual roadway layout (11), finally stabilizing it.

INDUSTRIAL APPLICABILITY

Figures 4A, 4B and 4C exemplify, according to some embodiments, said signalling (12, 13, 14, 15, 16, 17, 18) as they could be seen by the driver if they were projected in night or twilight circumstances onto the stretch of road (11) surface ahead. Light beams (13) are herein appropriately directed and shaped to frontally represent the prediction of the upcoming kinematic path of the vehicle in its upcoming and most significant moments. According to some embodiments, a laser light source, properly oriented and shaped by means of a scanner or other diffuser means already available at the state of the art (hereinafter referred to as simply "the projector") is the most effective way to convey the above messages due to excellent performances in directionality and concentration of light intensity (this does not exclude the use of other forms of concentrated light projection). The preference of laser sources is therefore due to purposes of higher visibility and sharpness. According to some embodiments, the projector is kept pointed downward, radiating within allowed intensity ranges and featuring conservative measures of automatic shutdown according to fail-safe approaches. According to some embodiments, the projector is installed in proximity of vehicle headlights, in order to always be underneath the sightline of drivers, never intercepting it. Moreover, the light beams are oriented and actively controlled by the scanner/diffuser to avert any possibility of dazzle towards other divers, especially those approaching from the opposite direction (also relying on optical data). As per similar well- known stabilizing methods for video images capturing/tracking, stabilization methods by inertial sensors can be adopted in some embodiments in order to correct all issues that affect projector elevation, image depth and lateral distortions arising as a result of the car's front chassis bumps. Together with the stabilization by means of actuators (depicted in Figure 6 with an input to the projector), the projection carried out by the scanner/diffuser can be delimited in the middle of a wider projectable area, thus preserving all border areas for compensation and stabilization purposes only. This additional embodiment feature would help to restrict the actual mechanical excursion for the whole projector optics. According to some embodiments, the projector is adapted to actuate a control on the adequate overlap between whatever is projected onto the road surface (11) and the actual geometry of the track, stabilizing it and adjusting its shape. This can also be achieved by optically sensing the environment or by other detecting means available at the state of the art. According to some embodiments, deformations of the light graphics projected upon the road pavement due to its planarity irregularities are as well corrected by a feedback from an optical sensing unit positioned in proximity of driver's point of view. For all embodiments according to the present invention, a suitable level of accuracy and integrity must be established to ensure that real-time performance calculations do not mislead drivers or pilots. The way said embodiments are conceived and aimed, given their dependence on various parameters, measurements and modeling, can be called upon to detect, manage and determine scenarios of complexity not always definable with the desired certainty and confidence. However, the vocation to safety can suggest the way forward to overcome such uncertainties consistently: having to face levels of uncertainty not always exactly definable, system evaluations should remain around more conservative margins (meaning considering worse scenarios) between the two possible limits within which the uncertainty can be attested. The achievement of the present invention is also to find solutions and algorithms avoiding to even fall into the opposite, that is provide unjustified alerts and signalling, as well counterproductive: generate noise and divert the attention of the driver, since the true vocation of the present invention is to promote a greater attention to the human factor and ergonomic aspects. System logics shall be appropriately set up to obtain and keep trustworthiness and all essential characteristics even enabling to take direct control over vehicle systems in partial or full authority (braking, steering systems, ESP, ARS, external lights). ONE MODE FOR CARRYING OUT THE INVENTION

One further exemplary embodiment connoted by higher and improved predictive features will now be expounded with reference to Figure 6, wherein is prefigured an architecture which could be differently integrated and laid down according to further forms of embodiments and to what implementation criteria would recommend. Herein, the projector is driven by an input from unit block (604) designated "GGCU" (Graphics Generator and Control Unit), which in turn receives the final result which collects all various esteems processed by the other three main identified functional units (601), (602) and (603). Unit block (604) GGCU relies on the whole information in a numeric form (also vectorial) which is suitable to be first converted and codified in graphic form, and then immediately projected by the scanner (and made available onscreen). According to some embodiments, block (604) controls projector and screen (output CTRL) so that they can display the following relevant information:

- Track marking (12), highlighted along the centreline and overlying the actual stretch of the road ahead (11)

- Estimated Vehicle path (13), simulated over the upcoming stretch of road (11) at the current vehicle's motion conditions

- Signalling of path criticality (16), (17), as estimated along the stretch of road at plausible motion conditions, as below exposed.

- Spatial references of the estimated vehicle stop distance (14) determined both longitudinally and laterally

- Additional symbols, pictograms, vectors, alphanumeric indications, figurations, standard symbols of alert (15), in support of the above graphic representations and added at any appropriate position within the projectable area.

Figures 4A, 4B, 4C expose a set of final graphics addressed to the driver, as samples of typical scenarios, which the system would be capable of outputting by properly combining the above-listed key elements according to some embodiments. In order to achieve a technical implementation of an embodiment able of such performances, the three logical-functional nuclei have been conceptually identified so that they can process the necessary information, thus allowing the (604) GGCU to represent what is mentioned above. The said three nuclei are focused on: (601) acquiring and processing the constraints imposed by the geometry of the stretch of road, (602) predicting the plausible kinematic behaviour of the vehicle, and (603) detecting and classifying all conditions of incompatibility between the two preceding constraints of track and motion. Given the precondition whereby in order to allow this exemplary embodiment to obtain credible results (i.e. that the three scopes of operation proceed independently from each other), (601), (602) and (603) have been limited to the three following functional unit blocks, interconnected as shown in Figure 6. (601) ATGM in Figure 6 - Available Track Geometry Mapper is the unit block returning the geometry (3D) of the road track in the reference system originating from the vehicle and extending longitudinally ahead. In such embodiment it includes a 3D map of the road track over which it identifies the vehicle position provided by GNSS satellite signals (Global Navigation Satellite Systems: GPS, Galileo etc.). Said signals can also rely on some currently-available or undergoing-development improvement solutions in order to refine precision (augmentation systems for GPS, EGNOS, WAAS and SBAS). (601) Similarly to methods known as "Dead Reckoning" and accessing further vehicle chassis sensor measurements, ATGM allows an even better estimation of the actual position (accurate position updater) by matching and balancing it with previous position fixes which are updated after integration over time of speed, acceleration, and steering-angle data. In this way, ATGM relies on a larger sample of position measurements upon which it can weigh up the average for the actual position. In case the route includes alternative paths, such as crossroads or intersections, (601) ATGM, in the same way as traditional satellite navigators, can also manage destinations and specific paths, thereby allowing this embodiment to generate signallings and safety alerts that are consistent with said specific paths. Information from driver's selection of turn signals can also be considered for the above said identification and signalling purposes, consistent with specific paths, according to some embodiments. The above embodiments can moreover succeed in including directional orientation features within the projected area on the road. All of this must not exempt the system from considering the innate criticalities of such crossroads, and said system must nevertheless alert as to the need for suitable decelerations even in the absence of any pre-set destination or path. According to some embodiments, the ATGM unit block (601) can also manage the acquisition of information from environment-sensing units so that it can highlight potential obstacles that may affect the safe motion of vehicle. The output from this unit block is identified in Figure 6 by the vector string T (for Track), which is positioned in a reference system strapped to the vehicle, adapted to represent the road track ahead and superimposed over it while moving forward. T extends longitudinally towards the proceeding direction for a span long enough to let the receiving unit (602) VDKS process its own quantitative evaluations, as exemplified below. (602) VDKS in Figure 6 stands for Vehicle Dynamic to Kinematic Simulator. This is the unit block encompassing the processing core, expectedly characterized by a considerable demanding calculation and intercommunication activity, aimed at the quantitative and predictive estimate of the crucial kinetic variables in the outmost domains of space and time. According to this exemplary embodiment, (602) VDKS is outlined for general traits only, as this exposition is not applied to any specific type of vehicle. Basically, (602) VDKS is adapted to perform numerical processing able to generate simulation sequences starting from embedded physical modelling. (Differential) equations representative of the vehicle response (which convey the various dynamic interactions into kinematic terms of speeds, accelerations and suitable distances) are processed on the inputs of the parameters the way they are measured.

A significant set of parameters identified as physically relevant for the present exemplary embodiment is reported below, wherein said parameters can be received and processed in any suitable order, and are not limited to the present set, nor are aimed to be herewith exhaustive. Said parameter inputs are laid down along the lower interconnections of Figure 6 and come from valid, up-to-date measurements of:

- Actual vehicle speed, detected by all available wheel speed transducers;

- Vehicle acceleration - longitudinal, lateral, vertical - from an inertial reference system and 3D accelerometers;

- Attitude, angular velocity, angular acceleration, from inertial reference system attitude & gyro.

- Vehicle actual mass, estimated throughout different accuracy levels, is obtainable from presence sensors at each seat (also quantitative), in the car boot and from fuel quantity, or from a measure of the overall load on the suspensions/shock -absorbers.

- Steering angle or turning radius,

- Activation status of ABS, ESP, ASR (traction control) systems in order to get a significant measure of the road- holding for longitudinal and lateral acceleration (deceleration) actually available. Less advisable on a frequent basis, but to be nevertheless kept into consideration, is the possibility of collecting the road- holding information also through human intervention by allowing the driver to apply even hard braking. This measure would also allow, at scattered intervals, to instruct the system about tyre performance, and balance it.

- Tyre-to-road friction estimation, methods for the definition of the dynamic reaction provided by the tyres against the pavement, all collected within the "surface detection" block in Figure 6. The unit block dedicated to surface detection, at the bottom of Figure 6, is also intended to make use of inputs obtained from image processing (aimed at detecting the roughness of the road surface from its visual appearance, or optically detecting the bumps and hollows due to the roughness) through OAT (Outside Air Temperature) sensors and rain detectors, from information about the ground disruption and disconnection data coming from /shock-absorber excursions for longer wavelengths and, lastly, if the above still turns out to be insufficient, by manual inputs from the driver on the state and contamination of the road surface by water, ice or mud. Finally, there are reasons to believe that it could be practicable to allow for the use of a probe temporarily in contact with the road surface, aimed at returning a measure of road grip. For the sake of completeness, reference is made to the direct and indirect methods exposed in the publication "Road Friction Estimation" Part II, IVSS etc. as also mentioned in said patent application EP 2 618 108 at Paragraph [0031].

As mentioned above, further inputs to (602) VDKS in the embodiment of Figure 6 are those from (601) ATGM:

- Geometry of the stretch of road ahead;

- uphill/downhill slope, banking angle, concave or convex irregularities of the stretch of road ahead;

- ground disruptions and disconnections, and unpaved sections.

For this exemplary embodiment, unit block (602) VDKS carries out a process of simulation characterized by high reliability in meters and moments very close to the present moment and current circumstances of motion. However the simulation gradually loses its consistency for farther meters ahead, going towards predictions for subsequent moments and meters where the continuity of the conditions above cannot be assured. Nevertheless, their relevance can be appropriately considered and measured, and that task will be implemented by unit block (603) SCWU. The object is to assess the compatibility of the estimated vehicle path (Course) along with the stretch of road ahead (Track - input from (601) unit ATGM), triggering the appropriate warnings and furthermore returning their extent of criticality, thus satisfying the warning purposes that this exemplary system embodiment is in charge of. The exemplary embodiment in Figure 6 also shows how all connections of inputs and outputs are laid down, and which the main variables subject to processing are. Unit block (602) VDKS is depicted partitioned into one main section (Central Logic Responder) where recurring processing tasks reside to resolve all equations characteristic of vehicle motion, and three other interface modules (2A - Speed Mapping, 2B - Speed Derating, 2C - Output Selector). Said equations are being updated and supplied with all physical parameters measured as above. 2A and 2B are in charge of interrogating recurrently and limited to what is of real interest to the Central Logic Responder, and forwarding the two respective critical outputs V^MAX and v^SAFE for evaluation by block (603) SCWU. V^MAX and v^SAFE, once compared with current speed V, will allow SCWU to return its output x(V) and, lastly, to govern the GGCU unit. The processing for this exemplary embodiment is carried out by the Central Logic Responder in response to interrogations of the two interface blocks 2A and 2B, allowing each to deliver their respective output, as exemplified below:

Interface block 2A is in charge of starting up the mapping process of the road track T in terms of what the logics of block (602) VDKS esteems to be the maximum speeds currently sustainable by the vehicle v^MAX (speed mapping process). Such v^MAX are the maximum calculated speeds at current driving conditions (mass, road-holding etc.) i.e. those ensuring both to turn and to rely on stop distances always inside the road track T and its constraints, meter by meter along the longitudinal variable "I". Thus, all various factors contributing to the dynamic response of the vehicle, as later translated into kinematic terms, are herewith synthesized and reduced into a simple mono-dimensional sequence of speeds along "I". Furthermore, interface block 2A ensures that the operation of the logic block (602) VDKS be applied only to the genuinely-significant stretch of road called SLS (Significant Longitudinal Stretch) ahead of the vehicle, and along the geometry of the road track T. The output by 2A is designated "V ^AX(SLS)\ to indicate that interface block 2A, after sequencing meter by meter its interrogations to the Central Logic Responder of (602) VDKS inside the SLS, first receives the longitudinal sequence of V^MAX(I) (max-speed mapping) and then packs them throughout the whole extension of the SLS, and forwards them to unit block (603) SCWU for its subsequent evaluation activity. Note that, according to some embodiments, the SLS can initially be a default-length interval (SLS₀ conservatively, but laboriously long), to be then subjected to continuous corrections to follow (SLS_CORR), in the light of what the longitudinal extension is actually found to be significant by unit block VDKS, after learning which criticalities the road track T will involve to face. This limitation of mapping the v^MAX along a shorter stretch SLS coRR ^< SLSo aims only to achieve further economies of calculation to the extent they may be deemed beneficial. The output V^MAX(SLS) by 2A, in summary, conceptually identifies the kinematic constraint that must imperatively be observed. It aims to state within which maximum and inviolable limits it is guaranteed as an extreme ratio the vehicle road-holding inside its roadway without overrunning it, and in observance of its current dynamic constraints.

Interface block 2B is in charge of a different sequence of speeds to deliver to unit block (603) SCWU, this time the "safe" speeds still calculated along the significant stretch of road SLS along road track T, and designated as "V^SAFE(SLS)\ The v^SAFE sequence is extrapolated from the previous V ^AX(SLS) sequence: Figures 7A and 7B give a qualitative representation of one transformation according to the exemplary embodiment of Figure 6 (in the time domain, however, univocally transferable to the space domain, longitudinally to the track): the profile of maximum speeds V ^AX(SLS) is basically "derated" by applying a penalty as a result of the vocation of the system to look forwards. Critical stretches of road ahead (sharp or hairpin bends, winding roads, ref. point "C" in Fig 7A) are "unearthed" by (602) VDKS to impose further limitations on the maximum speeds above, moderating them by imposing decelerations that are softer and certainly safer than those sustainable by the vehicle in known extreme conditions (angle β, derivative of the velocity in time). The extent of these decelerations, identified by angle a, is still dictated by the central logic unit (602) VDKS, and also takes into account safety constants and preset margins (K). According to some embodiments, the angle a can be updated according to vehicle current dynamic performances (mass, tire-to-road friction), and is also contextualized into the particular geometry of the impending road track (uphill, downhill, bank angles, concave or convex elevation irregularities). This second output V^SAFE(SLS) has been isolated in order to identify which "potential of safe maneuverability" the vehicle is providing in its current motion conditions. Thus, in addition to the maximum alert level triggered in Figure 7A for speed V_3> an intermediate level is introduced that warns of circumstances which are not entirely free from hazards even at speed V2. Interface block 2C is the ultimate one in the exemplary embodiment of Figure 6, exclusively in charge for communication with unit block (604) GGCU Graphics Generator and Control Unit, provided with the final result of all the evaluations by (602) VDKS. Interface block 2C acts as a signal selector/mixer, operating in response to control input x(V) from (603) SCWU.

Unit block (603) SCWU (Speed Comparator and Warning Unit), as will be further expounded below, in detecting:

The current speed (V-i) coming from wheel speed transducers, is below v^SAFE (its current punctual value, but also near this value (within a speed interval that is reasonable with those in SLS, as explained below) drives the selector 2C not to forward anything to unit block (604) GGCU or, alternatively, provide it with the geometry of the stretch of road T_Si_s- Unit block (604) GGCU will take care of depicting it with meanings and/or color codes for normality, generating the esteemed vehicle path (13) and all signals as in Figure 4A.

Note: it is a well-recognized advantage for some embodiments, even the single functionality, to emit the mere track marking (12) in order to better highlight the stretch of road ahead in low-visibility conditions and upon the driver's request.

- The current speed (V₂) is above v^SAFE but below the v^MAX, drives the selector 2C to forward to unit block (604) GGCU the geometry of the stretch of road TSLS and denote it with alert meanings (13) in its own color codes, besides further side-signalling (15) (16) to be projected as in Figure 4B.

- The current speed (V₃) is above v ^AX, drives the selector 2C to forward to unit block (604) GGCU the geometry of the estimated vehicle path CSLS (where CSLS stands for "Course", trend, proceeding along the SLS) as kinematically simulated by unit block (602) VDKS in the domain of space, and no longer able to observe the centerline of the stretch of road or its representation (track marking) (12). C_SLS is denoted by meanings of maximum alert and criticality, and drives (604) GGCU to generate the signals as per Figure 4, according to some embodiments in a flashing color code at high frequency (13) (17), together with side-signalling (17), (18). By setting coefficient K, the system embodiment can be calibrated to adjust the residual margin for cases of extreme emergency maneuvers, which must be flawless in order to succeed. The calculated Course CSLS(V) originating the estimated vehicle path signal (17) per Figure 4C, as processed by (602) VDKS, is now for the first time a distinct entity and deviates from the Track TSLS originating the track marking signal (12), no longer subsisting the minimum conditions to comply with the latter (12). The two calculated paths (CsLs(V) and T_SLS) however don't completely "ignore" each other: the Central Logic Responder returns a lateral control of the calculated Course CSLS(V) by imposing upon it to follow the same steering sequence as suggested by the stretch of road (11) and by the Track Marking (12), along a trajectory (17) that turns out to be irreversibly divergent. What will be projected is its progressive deviating from the stretch of road (11), for turning radiuses which, although minimal according to what high speed allows, will not be enough to ensure a safe road-holding. Thus, among the innumerable possible escape trajectories, one particularly relevant and significant is isolated and represented (13)(17): the one observing bends as adherent as possible to the stretch of road (11), but with dramatically wider curvatures. The investigation in the longitudinal direction by unit block (602) VDKS as well will trigger further alerts whenever any incompatibility between the availability of the stretch of road (11) and the stopping distance (14), simulated along the estimated vehicle path (13) (17), will be detected. The sense of criticality will aim at deterring categorically any disposition of the driver to follow the signalling (17) of the Course C_SLS(V).

Unit block (603) SCWU in the exemplary embodiment of Figure 6 - Speeds Comparator and Warning Unit is the Central Warning System, functional unit adapted to discover and quantify in terms of entity and criticality the incompatibility conditions detected for vehicle motion. The information it is provided with is characterized in this embodiment by a highly comprehensive content of data, comprising everything as a result of the vehicle maneuverability and the geometry of the stretch of road (11). It is herein furthermore fed by inputs of speed and actual position of the vehicle. With reference to one more embodiment per Figure 7B, it should be noted that the logics of alert generation is not meant as limited to the arithmetic "punctual" comparisons above (greater vs. lesser) of actual speed against the other two speeds V^SAFE and v^MAX. In fact, relying on speed profiles available even for upcoming intervals, block unit (603) SCWU can "lean forward" and extend its evaluation tasks throughout the persistence of some "adverse trends" of the actual speed, inducing some continuity from latest moments. Useful warnings may in fact well arise also in cases in which it is the (plausible) projection of the current speed (V2) to interfere with the other two speed profiles v^SAFE and v^MAX for the upcoming instants. Figure 7B shows this feature conceptually using some embodiments where unit block (603) SCWU, being aware of both the historical recent driving profile and the deceleration limit β allowed in that stretch, "projects forward" for a few seconds the current unsafe driving attitude of the driver, showing him an immediate maximum- level alert. This happens despite the intermediate risk level zone being in force. According to further embodiments, (603) SCWU is in charge of additional outputs for daylight use: consistently with what is graphically represented, one to a dashboard screen (22), one to a tone generator (20), and one to the vehicle speedometer (21) adapted to show in color codes an arc in proximity of its needle, in order to give account of the extent of speed decrease necessary to restore safe driving conditions, and as depicted in Figure 5. A reference also deserves further system embodiments adapted to the Aviation sector, wherein applied to aircrafts landing and takeoff procedures and, additionally, for ground handling along aerodrome layouts during the in and out taxi phases. According to some embodiments, the present invention is adapted to integrate the signalling features of systems commercially available and known in the Aviation Industry as ROAAS (Runway Overrun Awareness and Avoidance System) or ROPS (Runway Overrun Prevention System) or further analogous systems aimed at assisting during landing phases. This is achieved by interfacing the above exposed emission step (103) and/or block device (203) as per Figures 1 and 2, wherein they are adapted to generate and project the estimated aircraft path, stopping distance, and additional signalling upon the actual runway surface during landing. The advantage and purpose is again to keep the pilots' sightline and attention upon the runway ahead. According to these embodiments, the processing means needed to display the above-said features by (103) and (203) are adapted to include all environmental and specific information from said ROAAS/ROPS systems within processing step (102) and block device (202). The main additional information needed is already available to the ROAAS/ROPS systems from airframe Air Data Computers such as airspeed, wind direction, air temperature and pressure, airfield elevation, aircraft load and aerodynamic configuration etc. According to these embodiments, the compatibility check is herein performed by said processing step (102) and/or block device (202) as a function of runway geometry in terms of length and borders, together with its surface status and contamination, as is well accounted. According to some embodiments, the information is adapted to be simply projected in the basic exemplary form of a single displayed alert not to proceed with landing and triggering a timely go-around action.

According to some embodiments, the system is adapted to assist during the aircraft take-off phase as well, providing pilots with signalling that is likewise aimed at reducing exposure to runway excursion risks. This is again achieved by information projected on the actual runway surface and is implemented by the same above exposed emission step (103) and/or block device (203) as per Figures 1 and 2, after being properly adapted in conjunction with processing step (102) and/or block device (202) to process the compatibility checks between aircraft performances on ground and runway geometric and physic constraints. According to some embodiments, the information is adapted to be just projected in the basic exemplary form of a single displayed point of non-return, beyond which it is imperative to go airborne.

According to some further embodiments, the system is adapted for the ground taxi use, mainly focused for the crew to follow signs for directional orientation: the whole laser projection system, appropriately driven by the Airport ground traffic control (in cases of disparate paths only) is adapted to provide nightlight directions along the correct path to follow within the whole aerodrome layout, up to the parking/apron areas (night guidance, the same way as "follow me" vehicles do). Indeed, the system as it is set down in the exemplary embodiment in Figure 6 is already well capable of managing and accurately assisting during such movements and to project the path to follow onto the ground. Again with reference to the exemplary embodiment as per Figure 6, the sequence of waypoints from the Airport Ground Traffic Control would enter the system via the "NAV" input in the same way as a preset GPS navigator would do, while the feature of compatibility check with the track would be triggered only below definite speeds (tentatively 50-70 knots) so as not to interfere with the most critical phases of take-off and landing. According to some further forms of embodiment, during post-landing deceleration, the projected lighting path could accurately indicate through which of the multiple runway lateral way-outs it is safe to rapidly free the runway at current speed conditions.

It is to be understood that the described exemplary embodiments of the present invention can be the subject of additions, modifications and variations which are obvious for those skilled in the art and which are not to be limited to the specific embodiments disclosed. Modifications combinations of features of disclosed embodiments, as well as other embodiments, are intended to be included within the scope of the appended claims. It is also to be understood that, to Figures comparable to those herewith depicted and exposed, further different forms of representation, Figures, symbols, pictograms, vectors, alphanumeric indications, moving projections and graphic animations or anything else equally suitable to represent and effectively render the circumstances of practicability and safety of the road are intended to be included within the scope of the present invention and its appended claims. Said additional forms of representation may differ from the most immediate pure representation of the trajectory of the vehicle itself, herein preferred for reasons of clarity.

Claims

1. Method (100) for assisting in driving a vehicle comprising the following steps:

- acquiring the vehicle position by means of satellite signals;

- acquiring (101) the geometric constraints of the road track (11) where the vehicle is moving along;

^■ acquiring the current conditions of motion of the vehicle;

processing (102) the data of current conditions of motion of the vehicle to identify the current potentials of maneuverability of the vehicle;

checking the compatibility, using the acquired data, between the geometric constraints of the road track (11) where the vehicle is moving along and its current potentials of maneuverability;

displaying (103) of projected light signalling upon the stretch of road surface ahead of the vehicle, as a function of said compatibility check.

2. Method according to Claim 1 wherein the acquisition of vehicle position is performed by using satellite signals integrated and/or refined by inertial sensors and/or environment sensing units.

3. Method according to one or more of the preceding Claims wherein the acquisition of the geometric constraints of the road track (11), where the vehicle is moving along, is performed by using a stored map.

4. Method according to one or more of the preceding Claims wherein the acquisition of the geometric constraints of the road track (11) where the vehicle is moving along, is performed by environment sensing units adapted to acquire either the geometry of the track, and/or the presence of foreign objects and/or obstacles.

5. Method according to Claims 2 and 4, wherein said environment sensing units are of optical, radar or sonar type.

6. Method according to one or more of the preceding Claims Characterized in that it comprises also a step of acquiring the current information about external environmental conditions and in that said information about external environmental conditions is processed and integrated with the current conditions of motion of the vehicle, in order to refine the estimate of said current potentials of maneuverability of the vehicle.

7. Method according to one or more of the preceding Claims wherein said processing of data for estimation of the current potentials of maneuverability of the vehicle comprise the determination of one minimum turning radius and/or available lateral excursion, and/or one longitudinal stopping distance.

8. Method according to one or more of the preceding Claims wherein said processing of data for estimation of the current potentials of maneuverability of the vehicle comprise an estimation of the vehicle path (13).

9. Method according to one or more of the preceding Claims wherein the compatibility check comprises the comparing of acquired road track (11) where the vehicle is moving along with said estimated vehicle path (13).

10. Method according to one or more of the preceding Claims wherein the compatibility check comprises an evaluation of the compatibility level between the geometric constraints of the road track (11) and the estimated current potentials of maneuverability of the vehicle.

11. Method according to one or more of the preceding Claims 5 wherein said projection of light signalling comprises the projections upon the stretch of road surface ahead of the vehicle of the estimated vehicle path (13) and/or of the road track (12) where the vehicle is moving along.

12. Method according to one or more of the preceding Claims 0 wherein said projection of light signalling comprises the projection of warnings and alerting signs (14, 15, 16, 18) as a result of the compatibility check, and/or warnings (20, 21, 22) in the internal vehicle cabin.

13. Apparatus (200) for assisting in driving a vehicle 5 comprising:

- means of acquisition of vehicle position by satellite signals;

- means of acquisition (201) of the geometric constraints of the road track (11) where the vehicle is moving along;

- means to acquire the current conditions of motion of the !0 vehicle;

- at least one processing unit (202) adapted to:

- process (202-1) the data gathered by said acquiring means about current conditions of motion of the vehicle in order to identify the current potentials of

:5 maneuverability of the vehicle, and

- check (202-2) the compatibility, using the acquired data, between the geometric constraints of the road track (11) where the vehicle is moving along and said current potentials of maneuverability;

- at least one light generator (203) adapted to project light signalling upon the stretch of road surface ahead of the vehicle, as a function of said compatibility check.

14. Apparatus according to one or more of the preceding Claims wherein said acquiring means of the geometric constraints of the road track (11) where the vehicle is moving along comprise hardware and software means wherein a map of said road track is uploaded and stored.

15. Apparatus according to one or more of the preceding Claims wherein said acquiring means of the geometric constraints of the road track (11) where the vehicle is moving along comprise environment sensing units.

16. Apparatus according to one or more of the preceding Claims wherein said acquiring means of vehicle position comprise inertial sensors and/or environment sensing units integrating and/or refining said acquiring means of vehicle position via satellite signals.

17. Apparatus according to one or more of the preceding Claims characterized in that it comprises acquiring means for current external environment conditions and in that said processing unit is adapted to identify the current potentials of maneuverability of the vehicle by processing data as a function of both the current conditions of motion and the external environment conditions.

18. Apparatus according to one or more of the preceding Claims wherein said processing unit is adapted to identify the current potentials of maneuverability of the vehicle by determining one minimum turning radius and/or available lateral excursion, and one longitudinal stopping distance.

19. Apparatus according to one or more of the preceding Claims wherein said processing unit is adapted to identify an estimated vehicle path (13) from both the current potentials of maneuverability of the vehicle and the geometric constraints of the road track (11).

20. Apparatus according to one or more of the preceding Claims wherein said processing unit (202) is adapted to perform said compatibility check by comparing the acquired road track (12), where the vehicle is moving along, and the estimated vehicle path (13, 17).

21. Apparatus according to one or more of the preceding Claims wherein at least one light generator is controlled in order to project one light signalling consisting of a representation (13) of the estimated vehicle path, and/or of the road track (12), and/or of warnings and alerting signs (14, 15, 16, 18).

22. Apparatus according to one or more of the preceding Claims wherein the generator of light signalling projects visible laser light, mono or multicolor.

23. Method according to one or more of the Claims from 1 to 12 and/or apparatus according to one or more of the Claims from 13 to 22 characterized in that it is adapted for assisting preferably in low visibility conditions, in driving a vehicle or an aircraft, during aircraft ground taxi operations or during takeoff or landing phases.