HIGHLY AUTOMATED MODE OF ROAD TRAFFIC

Information

  • Patent Application
  • 20230063561
  • Publication Number
    20230063561
  • Date Filed
    February 12, 2021
    3 years ago
  • Date Published
    March 02, 2023
    a year ago
Abstract
Disclosed is a traffic system and method for motor vehicles (F), comprising, on the side of a traffic lane (12b, 12c), a dedicated track (21) in the form of a “U”-shaped gutter receiving, in a highly automated driving mode, one of the side wheel assemblies (16) of a vehicle, and comprising: • a running surface (22) substantially parallel to the surface of the roadway of the traffic lane (12b, 12c), • two side surfaces (23, 31) located on either side and above the running surface (22), one external (23) and the other internal (31) with respect to the footprint of the vehicle (F), the side surfaces (23, 31) being substantially perpendicular to the running surface (22), the internal side surface (31) maintaining the current ground clearance of the motor vehicles, wherein the side surfaces (23, 31) of the track are substantially continuous longitudinally and in that the system comprises a means for crossing the internal side surface (31) by lateral movement of the side wheels assembly (16) at sustained speed.
Description

The present invention relates to a bimodal, preferably electrically powered, traffic system, one of the modes being conventionally controlled by the driver and the other being highly automated, comprising:

    • a high-speed pseudo-level 4 highly automated driving mode (without instantaneous alertness) requiring only automotive-level reliability through backup mechanical guidance in emergency mode, due, for example, to a possible failure of the highly automated driving system;
    • a dynamic power charge of electric or hybrid vehicles in very low voltage and medium power;
    • a possibility of “platooning” to increase the traffic capacity without widening the roadway, the risks of which are mitigated by the presence of emergency braking, independent of the wheel/road friction coefficient, and its activation by inertia in the case of failure of the brake control system as described in the applicant's publication WO 94/26573.


The deployment of autonomous traffic in motor vehicles is currently facing a legal problem due to the fact that the legal responsibility in case of an accident is transferred from the driver to the manufacturer (and his suppliers). Indeed, most traffic accidents are currently of human origin and the driver is mainly responsible.


All current autonomous vehicle concepts are based on a “contactless” technology including sensors and electronic control systems, of “automotive” reliability, which are therefore not immune to failure (computer bug, blackout, etc.) and therefore most manufacturers limit themselves to level 3 driving aids requiring, on the part of the driver, constant vigilance in order to regain control of the vehicle and thus relieve the manufacturer of responsibility in the event of an accident in autonomous mode due to a malfunction of the “contactless” trajectory control system.


However, it is not disputable that drowsiness at the wheel remains one of the first causes of accidents on freeways and level 3 autonomous driving, by removing the need for the driver to keep his car permanently in the lane, does not go in the direction of reducing the monotony inherent to driving on a separate roadway such as a freeway or expressway, at sustained speed.


In the current state of traffic and travel speeds, a loss of visual cues such as a missing marking line or an unexpected interruption of the non-contact guidance system, even if only for a few tenths of a second, can lead to a runaway or a collision.


Although the aeronautical industry has developed electrical systems with a very high level of reliability, these systems are too costly for a car and above all require periodic maintenance programs with a high level of quality that is difficult to reconcile with routine maintenance as perceived by the driver of a car today. Indeed, if one only counts a few hundred thousand aircraft in the world, there are more than a billion vehicles on the road today, i.e. more than 5,000 times more!


It is therefore not surprising that all serious projects of autonomous cars “without immediate vigilance” are limited today to very low speeds (in traffic jams for example) to minimize the consequences of accidents or are oriented towards shared vehicles belonging to operators, who are the only ones able to cover the high acquisition cost and to ensure rigorous maintenance. In addition, the electric propulsion of conventional motor vehicles, despite the significant improvements it brings in the areas of atmospheric pollution and noise, comes up against a problem of weight for on-board energy storage.


In fact, 100 kg of lead-acid batteries are needed to store the equivalent energy of one liter of gasoline, weighing 700 grams. Although lithium-ion technology has quadrupled the mass capacity of batteries over the last twenty years, from 40 Wh/kg to more than 150 Wh/kg, the autonomy is still insufficient and represents an obstacle to the electrification of the automobiles fleet in developed countries.


On the other hand, the manufacturing and recycling of these batteries represents a substantial environmental impact that is contrary to the ecological objectives set for the coming decades of the 21st century.


Numerous studies have been carried out on the possibility of recharging vehicles without contact while driving on the basis of magnetic induction, but due to the distance between the transmitter and the receiver, the efficiency drops and the cost of the infrastructure remains prohibitive for widespread deployment.


Moreover, long-distance travel is increasingly taking place on dual roadways, expressways or freeways with separate roadways.


It is an object of the present invention to provide a dedicated track on the central side of separate traffic lanes for one of the side wheel assemblies of vehicles forming a mechanical lane keeping device having a “gutter” shape by the cooperation of two side surfaces located one on the bottom of the “cast-in-place” crash barrier that generalizes and the other on the lateral face of a continuous rail anchored in the roadway bordering said dedicated track.


This dedicated track, which advantageously uses the dead space between the crash barrier and the continuous marking line delimiting the fast-traffic lane, called the roughened zone, which does not encroach on the existing traffic lanes, allows for safe highly automated traffic, for equipped vehicles, sharing the roadway in a laterally staggered manner with the existing traffic, in order to allow for an economically viable transition to a progressive deployment of a highly automated traffic mode.


In his application PCT/FR93/00486, which was published in WO 94/26573, the applicant already demonstrated the safety advantages of such a guided traffic with all the side wheels running in a “gutter”. But, the described device required either the interruption of a side wall of the “gutter” to allow the entry and the exit of the wheels laterally, or a frontal entry and exit as in the “O-Bahn” system, which equips certain buses in ADELAIDE in AUSTRALIA since the Nineties, taking again the principle of the “Tracline 65” project experimented in the Eighties in Birmingham in England. Indeed, the interruption of a side wall poses a safety problem in case of failure of the steering system or in case of emergency braking in a zone where the side wall is interrupted.


The present invention provides a new solution for entering and exiting the dedicated track “gutter” by providing a means for laterally crossing the internal side surface by the side wheel assembly, at a sustained speed (which may be the current maximum speed in most countries on freeways). Advantageously, retractable rollers placed on the axle stubs of the side wheels of one of the side wheel assemblies, allow to momentarily relieve the load on the side wheels, by taking support on the extension of the roadway when the said side wheels are in line with the gutter for the purpose of landing, without impact, and extracting the said side wheel assembly, also at sustained speed.


The main function of this device lies in the existence, for the equipped vehicle running with a side wheel assembly in the gutter, of an emergency mechanical lateral guidance to control its trajectory in case of emergency mode due to a failure of the primary steering system in highly automated mode. As a result, the highly automated traffic mode according to the invention allows the vehicle to enter and exit laterally at any point of the shared infrastructure and this at a higher speed than in the case where it would have to enter the network through a specific entrance gate as it is the case in the “O-Bahn” system.


Thanks to these essential means of the invention, there is no longer a privileged entry/exit zone on the dedicated track that can be entered or left at any point. Advantageously, this exclusive dedicated track can be bordered directly by the “Jersey” type crash barrier or other lane separation wall of a divided roadway, the side surface bordering the roadway being carried by the lower part of the “Jersey” wall, thus advantageously using the unobstructed strip located between the “Jersey” wall and the continuous white marking line delimiting the lane.


It is thus understood that, even when installed on the left-hand side of a separate roadway (in the case of right-hand drive), this track dedicated to vehicle guidance retains all its characteristics so that the infrastructure thus modified can also be used by existing driver-controlled vehicles, thus greatly facilitating the introduction of the system and leaving the way open for a more or less rapid increase in the number of vehicles equipped according to the invention without requiring major initial investments.


Advantageously, the side wheels can be equipped with height-adjustable suspensions whose height varies in synchronization with the movement of the wheels to minimize body roll. The height of the suspension of the other side wheels can be adjusted in order to eliminate body roll when entering and exiting the runway of the dedicated track according to the invention, which will thus become transparent for the driver and the passengers.


By continuously measuring the lateral distance of the vehicle with respect to the side surfaces bordering the “gutter”, by one or more sensors placed in front of the front wheel, a servo-control of the vehicle's steering can thus maintain the front wheels in the center of the dedicated track, thus offering a simplified mode of highly automated driving that does not require visual detection of the marking lines. Although the measurement of this distance can be acquired continuously by several sensors, advantageously placed in front of the front wheel, measuring the lateral position of the vehicle with respect to the side surfaces bordering the dedicated track, a failure of this distance detection system is always possible and in this eventuality the contacts between the sidewalls of the tires, or the edges of the rims in the case of a flat tire, with the side surfaces of the “gutter” will be able to maintain the trajectory of the vehicle until an emergency stop. The vehicle can then exit the gutter by turning its front wheels at a standstill, and be able to free the dedicated track. This is the procedure for manual exit from the “gutter” that will be used by any vehicle that is not equipped and that by accident finds itself with all of its side wheels in the gutter. It is obvious to the man skilled in the art that in order to minimize failures, an obligation of close periodic control of the guidance and emergency braking devices will be put in place by the authorities.


The object of the present invention is then to provide electric mobility with a dynamic very low voltage power charge, arranged along the traffic lanes, from which each vehicle can be supplied with a voltage of less than 50 V AC and 120 V DC in order to comply with safety standards. It is reminded that although lower than the 400 V, the standard voltage of the battery pack, the very low safety voltage of 120 V DC still allows each 100 V block of the battery pack to be charged successively by switching, the batteries being composed of voltage elements of only a few volts.


In a preferred embodiment, the “Jersey” wall has above the first lateral guiding surface on each side a “third rail” connected to one of the poles of a very low voltage source and the vehicle has a lateral sliding shoe in order to ensure the electrical charge of the vehicle while driving, the other pole, connected to the rail, being picked up by a brush or any other known device


Indeed, in an advantageous way in terms of global energy efficiency (i.e. taking into account not only the energy to propel the car, but also to extract the raw materials from the mines and to transform them for its manufacture and that of its batteries), the present invention makes it possible to substantially limit the capacity and thus the weight of the on-board battery pack, thus reducing the quantity of C02 generated for its production. Moreover, the very low voltage of 120 V DC collected directly by sliding/rolling contact allows to supply directly the motor in autotransformer mode, without passing by the batteries, the latter being used only to supply the temporary additional energy or to recover the excess energy due to the ascents/descents and the changes of speed imposed by the profile of the roadway in highly automated traffic mode.


Finally, the present invention aims at reducing the current congestion of the network by allowing the “platooning” of several vehicles while mitigating the danger of such a system, which in essence reduces the distances of the vehicles in the platoon, by an on-board emergency braking device.


During the PATH (Partners for Advanced Transit and Highways) program tests in the 1990s, a 20% gain in aerodynamic drag was calculated if the vehicles were driven at a distance of 1 m, but this configuration led to difficulties in the control system and in particular to a risk of collision between the vehicles in the “platoon” in the event of emergency braking.


To alleviate this problem, according to the invention, an emergency braking caliper, allowing a deceleration of up to several g, is attached to the rear of the vehicle, preferably behind the rear wheel, to allow it to engage and disengage from the rail during entry and exit of the highly automated mode according to the invention. This device advantageously allows maximizing the reaction time for the management of ephemeral or permanent obstacles that may be on the track by substantially decreasing the braking distance, which may thus be of the same order or less than the 2 seconds prescribed for the current speeds on fast lanes or freeways. Consequently, the emergency braking device according to the invention increases the time allocated to the analysis of the nature of the obstacle and also avoids the degradation of braking performance in wet or icy weather.


Advantageously, this braking system will be associated with a telescopic bumper placed in the front bumper of the vehicles which operates by inertia, as on heavy towed trailers, by mechanically activating the emergency brake caliper, in emergency mode, in the event of failure of the on-board control system or total “black-out”.


The invention advantageously makes it possible to increase the traffic flow without necessarily requiring the creation of additional lanes on the roadway as is the case today, and thus represents a substantial economic and environmental interest.


Thus, instead of having to widen a freeway to two times three lanes when peak traffic exceeds 4,000 vehicles/hour, the invention will make it possible to increase the flow to more than 6,000 vehicles/hour at sustained speed, and this for a fraction of the cost necessary to create a third lane.


Then the rail, which offers:

    • on one hand, a rectilinear support, without abrupt variation as on an asphalt roadway, to the extraction roller to allow the wheels to enter and leave the “gutter” at high speed and
    • on the other hand, a lateral guidance to maintain the vehicle on its trajectory in emergency mode,


      will advantageously be made up of sections connected to each other allowing, by clamping and friction, to transmit the several tens of tons that the braking effort of a group of vehicles driving “in platoon” could apply on it.


By allowing a highly automated serene driving, due to the presence of the guidance system in emergency mode by mechanical contact, private individuals as well as professionals will be able to make road trips without having to maintain constant vigilance, thus bringing gains in terms of safety.


This will allow both individuals and professionals to travel on the road without having to maintain constant vigilance, thus saving productive time while working on other tasks for professionals or saving leisure time in the case of personal travel.


The traffic system for motor vehicles, comprises on the side of a traffic lane a dedicated track, in the form of a “U” shaped gutter, receiving in highly automated driving one of the side wheel assemblies of a vehicle and comprising:

    • a rolling surface substantially parallel to the road surface of the traffic lane
    • two side surfaces located on either side and above the rolling surface, one external and the other internal with respect to the foot print of the vehicle, the side surfaces being substantially perpendicular to the rolling surface, the internal side surface maintaining the current ground clearance of the motor vehicles, wherein the side surfaces of the rolling track are substantially continuous longitudinally and in that the system comprises a means for crossing, by lateral movement, the internal side surface by the side wheel assembly at sustained speed.


The means for laterally crossing the internal side surface may be a ramp, generally gently sloping perpendicular to the direction of travel, which connects the roadway to the upper end of the internal side surface.


The means for laterally crossing the internal side surface may be obtained by placing the running surface of the dedicated roadway at a lower height than the roadway.


The lateral crossing means of the internal side surface may be obtained by the combination of:

    • of a generally gently sloping ramp perpendicular to the direction of travel, connecting the roadway to the upper end of the internal side surface, and,
    • the position of the running surface of the dedicated track at a lower elevation than the roadway.


The upper end of the internal side surface comprises an auxiliary rolling surface, substantially parallel to the roadway surface and the front wheel of the side wheel assembly is equipped with an auxiliary support means capable of, while traveling at cruising speed, to temporarily relieve the load of the front wheel by taking support on the auxiliary rolling surface, the auxiliary support means being retractable by movement between a high position, where it preserves the ground clearance of the vehicle, and a low position where its lower contact point is substantially at the same height as the point of contact of the front wheel with the roadway. The auxiliary support means includes at least one roller mounted on a support arm hinged to the front wheel axle stub of the side wheel assembly and the internal side surface and the auxiliary running surface are carried by a continuous rail.


The rail has a third, ledge-like surface substantially parallel to and below the auxiliary rolling surface, the third surface and the auxiliary surface being pinchable by an emergency brake caliper connected to the vehicle structure to generate a braking force, by friction on the rail, that can reach a high value of more than 1 g in an emergency, independently of the coefficient of adhesion between wheel and road.


The side wheel assembly may be equipped with variable height suspensions and the heights of the suspensions:

    • decrease during the lateral ascent of the gentle slope ramp, with the auxiliary support means being lowered as the side wheel assembly moves over the auxiliary rolling surface to position itself plumb with the dedicated track, and then
    • increase to land the wheel on the rolling surface, with the support means simultaneously rising;


      resulting in a limitation or even cancellation of the body roll of the vehicle during the lateral entries, at sustained speed, on the dedicated track, the reverse sequence being used during the extraction of the wheels to leave the dedicated track.


Forward of the side wheel assembly, a sensor measures the lateral distance between the side wheel assembly and the outer side surface of the dedicated track and controls the vehicle steering device to maintain the side wheels of the side wheel assembly generally centered on the dedicated track while driving.


A “third rail”, powered by a pole of an electrical source, is positioned above and recessed from the outer surface of the dedicated track, with the return to the source provided by the conductive continuous rail, and known means are provided in the vehicle for establishing an electrical connection while driving by sliding/rolling shoe with the “third rail” and the continuous rail.


The yaw torque generated during emergency braking between:

    • the inertial force on the longitudinal axis of the vehicle, on which the center of gravity of the vehicle is substantially located, and
    • the braking force, on the rail,


      is taken up by the torque generated by the lateral forces formed by:
    • the contact force on the sliding/rolling shoe of the “third rail” located outside the dedicated track and positioned in front of the emergency brake caliper, and
    • the lateral contact force at the crotch of the caliper engaging the brake caliper on the rail.


A method for moving in and out of a freeway motor vehicle travel mode at a sustained speed to a highly automated travel mode, comprising a “U” shaped gutter dedicated track positioned at the edge of the freeway, capable of receiving a side wheel assembly of the motor vehicle by “vertical landing” for entry and “vertical extraction” for exit, the side wheel assembly being equipped with rollers fixed, in a vertically retractable manner, to the inner faces of the wheel spindles, the lower part of the rollers being, in the lowered position, substantially at the height of the wheel-road contact, comprising the steps:


to enter:

    • 1. approaching laterally to the dedicated track by action on the vehicle steering,
    • 2. lowering the retractable rollers to temporarily support, by resting on the auxiliary rolling surface of the continuous rail, the weight of the vehicle supported by the side wheel assembly when the side wheel assembly is plumb with respect to the dedicated track,
    • 3. raise the rollers to vertically land the side wheel assembly on the running surface;


      and to exit:
    • 1. lower the rollers, which rest on the auxiliary rolling surface of the continuous rail, and lift the side wheel assembly vertically off the running surface,
    • 2. activate the steering to move the side wheel assembly laterally towards the free roadway,
    • 3. continue moving until the side wheel assembly is on the open roadway, at which time the rollers are retracted upward to restore the vehicle's ground clearance and allow conventional open road travel.


This Method is completed in the case where at least the side wheel assembly is equipped with height adjustable suspensions in that the steps for:

    • “entering” include during phase 3: the suspension height of the side wheel assembly increases simultaneously with the retraction of the rollers;
    • “exiting” during phase 1: the suspension height of the side wheel assembly decreases simultaneously with the lowering of the rollers.





Other characteristics and advantages of the invention will be apparent from the description given below of an example of its implementation. Reference will be made to the appended drawings among which:



FIG. 1 represents an axisymmetric view of traffic (right) on a two-lane divided highway illustrating two platoons of 3 vehicles traveling in a highly automated mode according to the invention, sharing part of the roadway with conventional traffic.



FIG. 2 shows a frontal view of two cars travelling in a highly automated mode in opposite directions with their left side wheel assemblies engaged in the respective gutters according to the invention.



FIG. 3 represents the detail of the gutter allowing the highly automated mode of circulation of FIG. 2, the left wheel of the vehicle being only sketched.



FIG. 4 represents an axisymmetric view of an electric car equipped with the devices necessary for circulation in a highly automated mode according to the invention with enlarged views illustrating the auxiliary relief rollers.



FIGS. 5, 7 and 9 represent in axisymmetric views the transition sequence from free driving to driving in a highly automated mode, by crossing the ramp by the side wheel assembly and then landing into the “gutter” according to the invention.



FIGS. 6, 8 and 10 represent enlargements of FIGS. 5, 7 and 9 with the vehicle in transparency to illustrate the rollers temporarily allowing to relieve the weight of the vehicle during the passage from free mode to a highly automated mode.



FIGS. 11, 12 and 13 depict, in front view, the coordination of the height adjustable suspension with the lateral movement of the vehicle according to the invention to minimize/cancel body roll when entering and exiting the highly automated driving mode.



FIGS. 14 and 15 represent in axisymmetric views the disengagement and engagement of the emergency brake caliper on the rail as well as the assembly of the rail in sections.



FIGS. 16 and 17 show in top view and in axisymmetric view the recovery of the yaw torque exerted on the vehicle during emergency braking



FIGS. 18 and 19 represent frontal views of dedicated infrastructure of the slide or underground type, advantageously using the reduction of traffic lanes thanks to the highly automated traffic means according to the invention.






FIG. 1 illustrates a double-lane road or highway “a” with “right-hand” traffic comprising traffic lanes “b” and “c” separated by a concrete guardrail 1 of known “New Jersey” type. Conventionally, one finds successively from the outside to the inside:

    • the hard shoulder 10b, 10c of variable width;
    • the “slow” lanes, including the 11b and 11c roadways allowing access to and from the road (not illustrated) with double lanes “a”, usually 3.5 m wide, delimited by two ma lines, usually white, continuous on the right 2b, 2c and discontinuous on the left 3b, 3c;
    • the “fast” or passing lanes with roadways 12b and 12c, also usually 3.5 m wide, delimited by two marking lines, discontinuous on the right 3b, 3c and continuous on the left 4b, 4c and;
    • a central roughened strip of about 1 m wide 13b and 13c which can be reduced to 0.5 m in urban or suburban context separates the continuous marking line 4b, 4c from the concrete “Jersey” wall 1.


Light vehicles D and heavy vehicles E travel on lanes 11 and 12 in a conventional manner, under the control of their drivers, who keep their vehicles substantially centered on the lanes.


The light vehicles F1 to F6 circulate astride the marking line 4b or 4c in a “platoon” and in a highly automated way, in pseudo 4/5 mode (according to the SAE standard commonly defined by the authorities and the car manufacturers), without requiring any particular vigilance from their drivers, the vehicles F moving astride the marking lines 4b or 4c.



FIGS. 2 and 3 illustrate a cross-section of the central portion of the road “a”. In the center is the concrete guardrail 1 and two weir gutters 17b and 17c of the known “slot pipe” type of precast concrete comprising a discharge pipe 18 fed by drainage slots 13b and 13c located in the running surfaces 22. The gutters 17b and 17c are buried on either side at the base of the concrete guardrail 1. Vehicles F2 and F4 have their left wheel assemblies engaged in “U” shaped gutters 21b, 21c comprising:

    • a running surface 22 substantially parallel to and preferably below the roadway 12, resting on the weir gutter 17b or 17c;
    • an upper branch of the “U”, on the outer side with respect to the vehicle F, formed by a substantially vertical side surface 23 which can advantageously serve as the foot of the concrete guardrail 1, this surface 23 being surmounted by a substantially vertical and recessed “third rail” conductive side surface 24, mounted on an insulating support 25 This insulating support 25 can advantageously house the medium voltage cables 26, supplying the substations delivering the very low voltage to the vertical conducting surface 24.
    • a continuous rail 27 on the internal side with respect to the vehicle F fixed by the flange of its laminated profile 29 on the weir gutter 17 by bolts 28 which has three continuous surfaces:
      • a lower continuous surface 30,
      • a continuous side surface 31 and
      • an upper auxiliary rolling surface 32,


        all three of which are in cornice on the “U” shaped gutter 21.


On the rail 27, a gently sloping ramp 34 having substantially the height of the rail 27, formed of ramp segments is attached to the rail 29 attachment flange.


Accordingly, the substantially vertical side surfaces 23 and 31 serve as side edges, in a emergency mode, to keep the side wheels on the track by contact between the side wheel tire sidewalls 35 and 36, or the rim edge in the event of a flat tire, and the side surfaces 23 and 31. This emergency mode only occurs in case of failure of the steering control device (not illustrated) which is already fitted to certain cars with a type 3 automated driving mode. Advantageously, this steering control device is simplified, not requiring optical recognition, and being able to operate with simple lateral distance telemetry, by ultrasonic sensors 33 for example, to keep the front wheel 35 of the vehicle centered on the running surface 22 in highly automated driving mode according to the invention.



FIG. 4 illustrates a light electric vehicle F that includes the devices necessary for highly automated traffic mode according to the invention. It is a “right-hand drive” vehicle, comprising a left side wheel assembly 16 comprising the following devices specific to the invention:

    • a lateral distance measuring device 33, advantageously multi-sensor, preferably located in front of the right front wheel 35;
    • a retractable shoe 37 located at the bottom of the left-hand body;
    • a crossing means constituted by two assemblies 8, each assembly comprising a roller 38, 39 which can be raised and whose support arm 14 is actuated by the jack 15, preferably electric, being attached to the spindles 9 of the two left wheels 35 and 36 and;
    • a brake caliper 40, located behind the left rear wheel 36.



FIGS. 5-6, 7-8 and 9-10 illustrate the sequence of switching from conventional driving under the responsibility of the driver to the highly automated traffic mode according to the invention. The reverse sequence allows disengagement from the highly automated traffic mode according to the invention to conventional driving under the responsibility of the driver.


In FIGS. 5 and 6, the vehicle F is driving on the conventional lane 12b bordered by two marking lines, discontinuous on the right 3b and continuous on the left 4b. The distance sensor assembly 33 measures the distance between the vehicle F and the concrete guardrail 1. The rollers 38 and 39 are raised as well as the retractable friction shoe 37 and the emergency brake caliper 40 is raised and is located behind the wheel 36. If the system has detected the existence, for example by a geolocation system, of an add-on infrastructure according to the invention, that the distance to the concrete rail 1 is equal to a certain value and that the speed is sufficient, the change of driving mode can be initiated by the driver.


In FIGS. 7 and 8, the vehicle F, having engaged the change of driving mode, shifts to the left autonomously while driving at cruising speed, the left wheels 35 and 36 cross the marking line 4b and climb the ramp 34, simultaneously the rollers 38 and 39 are lowered by the rotation of the support arms 14 actuated by the jacks 15 and when the wheels 35 and 36 are plumb with the running surface 22, the rollers 38 and 39 resting on the upper rolling surface 32 of the rail 27 temporarily support the load of the wheels 35 and 36. As the rollers 38 and 39 rise, they land the wheels 35 and 36 on the running surface 22.


In FIGS. 9 and 10, the vehicle F has deployed the retractable shoe 37 located at the bottom of the left-hand body which has come into sliding/rolling contact with the conductive surface 24 which may advantageously be made of aluminum to minimize losses by Joule effect with a steel contact surface, a brush or a rolling/sliding shoe 56 (behind the jack 53) is in contact with the steel rail 27 to establish the return of the current and thus a dynamic electrical power charge in the order of 25-30 kW per vehicle is thus achieved. At the same time the brake caliper 40 has tilted and engaged the rail 27. The roller 41, resting on the rail 27, holds the linings 42 of the caliper 40 close to the three continuous surfaces 30, 31 and 32 without touching them.


With the high emergency braking capacity, greater than 1 g, independent of the tire/pavement adhesion conditions because the brake caliper 40 pinches the rail 27, the vehicles F1, F2, F3 and F4, F5, F6 can advantageously group together in a platoon with a distance of less than 1 m between vehicles as illustrated in FIG. 1. This allows a substantial increase in the throughput of the traffic lanes 12b and 12c by putting 2 or more vehicles in a platoon. Indeed, with platoons of 3 to 4 vehicles, the maximum throughput in vehicles/hour increases by 250% from about 1,700 vehicles/hour to nearly 6,000 vehicles/hour for the equipped traffic lane. Known devices for measuring close distances, such as ultrasonic devices, maintain reduced “intra-peloton” distances between vehicles, which results in a substantial gain in aerodynamic drag.


Vehicles grouped in this way can nevertheless leave the platoon at any time by means of a communication device between the vehicles of the “Wi-Fi”, “Bluetooth” or similar type. Indeed, before a split-lane junction, and not a simple exit that will in any case require a resumption of the conventional traffic mode, if the vehicle needs to take the right-hand branch, it will have to leave the highly automated traffic mode and will only be able to re-engage the highly automated traffic mode when it has entered the right-hand branch. The vehicle wishing to leave the platoon informs the vehicles in front and behind, which will automatically reduce or increase their speed to re-establish the required 2-second separation distance. For example, in the case of a speed of about 120 km/h, it will take about ten seconds to re-establish this regulatory distance allowing the exit of the platoon and the highly automated traffic mode according to the invention. When a large portion of the traffic is in the highly automated traffic mode according to the invention, and if the side lines are well detectable, a vehicle also equipped with level 3 autonomous driving will be able to carry out, without the driver's intervention, but under his vigilance, the maneuver of disengagement of the wheels 35 and 36 from the gutter 21 before the junction, then the change of lane to take the right branch of the junction in free mode, and then the re-engagement in the gutter 21 of the right branch. Reference beacons located on these junction zones can help the basic autonomous system, since it is level 3, to locate the vehicle precisely in relation to the infrastructure in case of reduced visibility (night, rain, fog, etc.).



FIGS. 11, 12 and 13 illustrate the sequence of switching from the conventional driving mode under the responsibility of the driver to the highly automated mode according to the invention in the case of a vehicle with variable suspension height, thus advantageously allowing to reduce or even cancel any vertical movement and/or body roll during this sequence.



FIG. 11 shows, in a frontal view, the vehicle F5 with “variable height suspension” driving on a conventional track 12c. The lateral distance measuring device 33 measures the distance of the vehicle F5 from the concrete guardrail 1, with the roller 38 raised; if the measured distance has a certain value, and the speed is sufficient to fit into the highly automated traffic mode, a change in driving mode can be initiated by the driver.



FIGS. 12 and 13 illustrate the vehicle F5 which, while driving at cruising speed, goes onto the gutter 21 and shifts to the left, the left front wheel 35 crosses the marking line 4b and when it climbs onto the ramp 34, the suspensions on the right side 51 are progressively raised while those on the left side 52 are lowered to cancel the roll, simultaneously the rollers 38 and 39 are lowered and when the left wheels 35 and 36 are plumb with the running surface 22, the height of the suspensions of the left wheels 52 increases to land, gently, the wheel 35 and the wheel 36 (hidden by the wheel 35) on the running surface 22. The roller 38 and roller 39 (hidden by roller 38) that temporarily took the loads from wheels 35 and 36 retract to have wheels 35 and 36 carry the lateral weight of vehicle F5 only.


In particular, FIG. 14 illustrates an advantageous joining system for the rail sections 29 that form the continuous rail 27 of the exposed mortise and tenon type. Thus, the front end of the rail section 27 in the direction of travel is in the form of an open mortise 29b and the rear end in the form of an open tenon 29a, and the connection can be made, for example, by three locked BTR screws. Advantageously, the end of the tenon 29a and the mortise 29b will be inclined in the vertical and horizontal planes to avoid a complete discontinuity in the height of the surfaces in a transverse plane. This system advantageously allows a tolerance on the length of the rail sections 29, facilitating their maintenance or replacement.



FIGS. 14 and 15 illustrate the emergency braking system according to the invention, which allows for platooning of light vehicles with a small inter-vehicle distance. This system is particularly adapted to mitigate the risk of collisions in highly automated operation where the trajectory and speed are out of the driver's control and his vigilance is not sustained. Indeed, thanks to a scan of the lane by radar or any other method allowing to detect vehicles or obstacles located on the trajectory, the control system adapts the speed of the vehicle, but in the case of impromptu occurrence of fixed obstacle or stopped/damaged vehicle the capacity of strong emergency deceleration, in any weather conditions, of the solo vehicle or of vehicles forming a platoon according to the invention, is thus much greater than what can be obtained by the conventional braking means of the vehicle which are limited by the wheel/road friction coefficient usually lower than 1.


In FIG. 14, the wheel 36 of the vehicle F has just been landed on the running surface 22 and the brake caliper 40 is in its free running position, tilted obliquely on the axes 48 and 49 behind the wheel 36. On the caliper support 45 integral with the left rear suspension arm 47 there is a pin 46 that corresponds to a hole 44 on the tilting caliper 40.


In FIG. 15, the brake caliper 40 is engaged on the continuous rail 27 by rotation about axes 48 and 49 which allow a tolerance on the height, the roller 41 holding the brake linings 42 equipping the three faces of the caliper in immediate proximity to the surfaces 30, 31 and 32 of the continuous rail 27. The vertical piston (or pistons) 53 is preferably located on the upper portion of the caliper 40. The pin 46 of the bracket 45 is engaged in the hole 44 to prevent rotation of the caliper relative to the rear axle on a transverse axis due to the eccentricity of the caliper 40 relative to its tilt axes 48 and 49.



FIGS. 16 and 17 illustrate the forces that are at stake during a high-powered emergency braking that generates a yawing torque due to the lateral shift between the braking force 57 of the vehicle, exerted on the continuous rail 27, and the inertia force 50 substantially in the longitudinal plane of symmetry of the vehicle. This torque is advantageously taken up by the torque between:

    • the force 54 exerted on the contact between the crotch of the caliper 40 on which a brake lining 42 is located and the surface 31 of the continuous rail 27, avoiding any possibility of disengagement of the caliper from the rail 27 and
    • the force 55 exerted by the pressure of the retractable friction shoe 37, which is free to deploy laterally in the highly automated mode of operation, according to the invention, to exert only a slight current collection pressure on the conductive surface 24, is blocked in retraction when the emergency brake caliper is actuated.



FIG. 18 illustrates an example of an aerial “slide” footbridge 61 of low cost due to the low weight of the light vehicles moving according to the highly automated traffic mode according to the invention, allowing the crossing of urban areas, pedestrians, roads, highways, railroads, rivers, etc. . . .



FIG. 19 illustrates the small size of the tunnel 62 needed for the dedicated track traffic of light vehicles moving according to the highly automated traffic mode according to the invention because of the precise lateral positioning of the vehicles. The system according to the invention has the advantage of allowing a large freedom on the width of the vehicles compared to the solution based on external rollers retained by the projects “Tracline 65”, “O Bahn” and more recently by the “Boring Company” of Elon Musk.


The previously described devices of the invention, allowing the lateral entry and exit of the highly automated traffic mode according to the invention on a road infrastructure in cohabitation with vehicles circulating in free mode, are particularly advantageous for solving the problem posed by the entry and exit of dedicated lanes, exclusively reserved for light vehicles, as illustrated in FIGS. 18 and 19.


The description and the drawings illustrate “right-hand” traffic, but it will be obvious to the person skilled in the art that this system is also valid for “left-hand” traffic. Also, the highly automated mode of driving is not restricted to electromobility or hybrid propulsion, and it is conceivable that ICE vehicles could take advantage of the benefits of highly automated driving and platooning in areas where electrification of the road will not be economically viable.


A substantial advantage of augmented road mobility, according to the invention, is that a transition from free-running to highly automated traffic according to the invention can be achieved on existing infrastructure without heavy investment.


When a substantial proportion of the vehicle fleet is equipped to travel in highly automated traffic mode, and because of the small width of the footprint of a guided traffic lane according to the invention, which allows for reduced infrastructure dimensions as illustrated in FIGS. 18 and 19, it will be possible to create an additional lane in a separate double lane or two-lane highway without requiring any real infrastructure work, by slightly shifting the position of the marking lines or by a limited reduction in the lane width.


Another substantial advantage of augmented road mobility according to the invention is the reduction of the size of the battery of “100% electric” vehicles, which will now be able to limit themselves to a capacity necessary to cover a distance of less than 100 km between recharges, representing a division by a factor of 3 to 5 of the weight of the batteries, with an impact on the weight, the cost, the need for reinforcement of the vehicle of thermal design and the environmental impact that the size of the latest generation of batteries imposes on “free circulation” electro mobility.


It goes without saying that the devices according to the invention can be adapted to other lane-separated road configurations, in particular single-lane roads in each direction, other forms of gutters and rails or to other vehicle structures, and the examples just given are only particular illustrations and in no way limit the fields of application of the invention.

Claims
  • 1. A motor vehicle traffic system (F) having on the side of a traffic lane (12b, 12c) a dedicated track (21), in the form of a “U” shaped gutter, receiving in highly automated driving mode one of the side wheel assemblies (16) of a vehicle, comprising: a running surface (22) substantially parallel to the road surface of said traffic lane (12b, 12c),two lateral surfaces (23, 31) located on either side and above said running surface (22), one external (23) and the other internal (31) with respect to the foot print of said vehicle (F), said side surfaces (23, 31) being substantially perpendicular to said running surface (22), said internal lateral surface (31) maintaining the current ground clearance of the motor vehicles
  • 2. A system according to claim 1, wherein said means for laterally crossing said internal side surface (31) comprise a ramp (34), generally gently sloping perpendicularly to the direction of traffic, which connects said roadway (12) to the upper end of said internal side surface (31).
  • 3. The system according to claim 1, wherein said lateral crossing means of said internal side surface (31) is obtained by positioning said running surface (22) of said dedicated track (21) at a lower elevation than said roadway (12).
  • 4. The system according to claim 1, wherein said lateral crossing means of said internal side surface is obtained by the combination of: of a ramp (34), generally gently sloping perpendicularly to the direction of traffic, connecting said roadway (12) to the upper end of said internal lateral surface (31) andpositioning said running surface (22) of said dedicated track (21) at a lower elevation than said roadway (12).
  • 5. System according to one of claims 2, 3 or 4, wherein said upper end of said internal side surface (31) comprises an auxiliary rolling surface (32), substantially parallel to the running surface (22).
  • 6. System according to claim 5, wherein the front wheel (35) of said side wheel assembly (16) is equipped with auxiliary support means (8) capable, while running at cruising speed, of temporarily relieving the load of said front wheel (35) by taking support on said auxiliary rolling surface (32), said means (8) being retractable by movement between a high position, where it maintains said ground clearance of the vehicle, and a low position where its lower contact point is substantially at the same height as the contact point of said front wheel with the roadway (12).
  • 7. The system according to claim 6, wherein said auxiliary support means (8) comprises at least one roller (38) mounted on a support arm (14) articulated to the axle stub (9) of the front wheel (35) of said side wheel assembly (16).
  • 8. The system of claim 5, wherein said internal side surface (31) and said auxiliary rolling surface (32) are carried by a continuous rail (27).
  • 9. System according to claim 8, wherein said rail has a third surface (30) substantially parallel to and below said auxiliary rolling surface (32), said third surface (30) and said auxiliary surface (32) being pinchable by an emergency braking caliper (40) connected to the vehicle structure (F) to generate a braking force, by friction on said rail (27), which can reach in emergency a high value higher than 1 g (9.81 m/s2), independently of the coefficient of friction between wheel (35, 36) and roadway (12)
  • 10. System according to claim 7, in combination with one of claims 2 or 4 wherein at least said side wheel assembly (16) is equipped with variable height suspensions (51, 52) and that the heights of said suspensions (51): decrease during the lateral ascent of said ramp (34) on a gentle slope, said auxiliary support means then being in a low position as the side wheel assembly (16) moves over the auxiliary rolling surface (32) to position itself plumb with said dedicated track (21), and thenincrease to land the wheel on said running surface (22), said support means (8) simultaneously rising,
  • 11. The system of claim 1, characterized by the presence, preferably in front of said side wheel assembly (16), of a sensor for measuring the lateral distance (33), of said assembly (16) from at least one of said outer side surfaces (23, 24), said lateral distance controlling the steering device of the vehicle to maintain, while driving, said side wheels (35, 36) of said side wheel assembly (16) generally centered on said dedicated track (21).
  • 12. The system of claim 8, wherein a “third rail”, powered by a pole of an electrical source, has a lateral contact surface (24) external to said track (21), the return to said source being made by said conducting continuous rail (27), and in that the vehicle is equipped with known means for establishing an electrical connection while driving by sliding/rolling shoes (37, 56) with said “third rail” (24) and said continuous rail (27).
  • 13. The system of claim 9, in combination with claim 12 wherein the yaw torque generated by the emergency braking between: the inertial force (50) on the longitudinal axis of the vehicle, on which the center of gravity of said vehicle is substantially located, andthe braking force (49), on said rail (27),
  • 14. A method for entering and exiting by lateral displacement, at sustained speed, from a open roadway motor vehicle traffic mode to a highly automated traffic mode restricted to a single traffic lane, comprising a dedicated track, in the form of a “U” shaped gutter (21) and placed at the edge of said open roadway, capable of receiving a set of side wheels (16) of said motor vehicle (F) by “vertical landing” to enter and “vertical extraction” to leave, said side wheel assembly (16) being equipped with retractable rollers (38, 39), fixed in a vertically retractable manner to the inner faces of the wheel spindles (9), the lower part of said wheels being, in the lowered position, substantially at the level of the wheel-pavement contact, comprising the steps:
  • 15. The method of claim 14, wherein at least said side wheel assembly (16) is equipped with height adjustable suspensions (51, 52) and in that the steps for: “entering” comprise during step 3: the suspension height of said side wheel assembly (16) increases simultaneously with the retraction of said rollers (38, 39);“exiting” includes during step 1: the suspension height of said side wheel assembly (16) decreases simultaneously with the lowering of said rollers (38, 39).
PCT Information
Filing Document Filing Date Country Kind
PCT/IB2021/051187 2/12/2021 WO