Method and equipment for motorway control

• US 6,320,515 B1
• Filed: 02/05/1999
• Issued: 11/20/2001
• Est. Priority Date: 08/09/1996
• Status: Expired due to Fees

• Current Assignee: Kjell Olsson
• Original Assignee: Kjell Olsson
• Inventors: Olsson, Kjell
• Primary Examiner(s): TONG, NINA C
• Application Number:
  US09/242,027
• Time in Patent Office: 1,019 Days
• Field of Search: 340/905, 340/907, 340/917, 340/909, 340/910, 340/911, 340/916, 340/918, 340/919, 340/920, 340/922, 340/924, 340/933, 340/934, 340/935, 340/936, 340/937, 340/938, 701/117
• US Class Current: 340/905
• CPC Class Codes: G08G 1/075 Ramp control

Abstract

The method and the means concern a system for control of motorway traffic, with focus on access control. The network characteristics of the traffic, according to the invention, is treated by traffic control functions based on the traffic as well as the access itself, as at the closest section upstream the access, and at connected parts of the road network. The invention goal is safer traffic and an effective utilization of the motorway. The system is creating possibilities for a dynamic traffic management with control of traffic flows. A smoother and better controlled weaving process is effected by preparatory actions and the functions create more margins, as well in space as in time, for the performance of the usually complicated and dangerous driving procedures on the motorway. Modern information technology is used as a means for carrying out the invented solutions.

Claims

1. A method concerning systems for access control of traffic at motorways and larger roads, where the access flow is controlled by information means, which directly or indirectly influence the access travel of the cars, and where the flow size is determined considering the flow size on the motorway, and where cars (A) from the access road interact with cars (B, C, etc) on the motorway while weaving together the respective flows, comprising;

limiting the flow of A-cars on the access road by a given target value, an allocated ration, which is related to a target value for the motorway flow,

dynamically correcting the said ration based on at least one of the following (a) and (b);

a. upstream measurements of traffic flow on the motorway, with a correction determined by the deviation between the said flow target value and said measured value, and where the said upstream measurement site is positioned a distance L1 from the access weaving zone, where L1 is that far, that flow-corrected access cars reach the motorway in time for weaving with those motorway cars, which have caused the flow correction, and where a target value for L1 is L1 ≧

v²/a, where v is an applicable velocity value for the motorway and a is an applicable acceleration value for the access, and the qoutient v²/a is covering (is larger than) the corresponding quotient of velocity and acceleration values for most of the applicable traffic situations,

b. at upstream exit, measurements on cars, which indicate exit, a roadbased equipment, which register information about the cars indicating exit, said information is used for estimating a correction of the downstream access flow, and the traffic density in the right lane of the motorway, on a distance L2 closest upstream the weaving zone for the access, where L2 is less than L1, is determined within a limit in accordance to that access flow, which is estimated for the weaving together with the said motorway traffic, including determination of target values for gaps between motorway cars, where said target values give a density between cars on the motorway, which seen over the corresponding access flow time period for two consecutive (A)-cars, is corresponding to an added gap for those motorway cars, giving space for at least one car, an access car.

2. A method according to claim 1, where the method includes a principal function, HF1, superior access control, which concerns an integrated access flow control for a plurality of accesses along a motorway, HF1 comprising:

selection of a plurality of accesses along a motorway,

determination of target values for motorway flows and access flows along the motorway, whereby each selected access is allocated a dynamic ration of traffic flow for access to the motorway,

measurements of flows by sensors on the motorway, which including the access flow gives the added flow downstream the access,

comparison of the actual flow on the motorway obtained from measurement, and the

corresponding target value, and at deviations larger then a selected level;

a correction is made, Cu, of the flow ration for at least one of downstream accesses, where the flow is increased or decreased dependent on the upstream motorway flow being too small or too large, and there is a succeeding correction, C1, of the flow rations for accesses that earlier have been given larger or smaller rations than the given target values,

a dynamically updating of allocated rations of accesses flows based on measured or predicted traffic situations,

an updating of said target values based on changed needs at the road network.

3. A method according to claim 2, where the method includes a principal function, HF2, exit control, which concerns control of exit traffic and preparations for the following access, HF2 comprising:

the exit process is performed in at least two stages, a first stage upstream of the weaving zone, a second stage, the weaving stage, where exit weaving is occuring,

and during the first stage, information is exchanged between cars and road based equipment, where cars are indicating turning to the right or the left, the road based equipment registrating the turning information about the cars, information is calculated or predicted on the resultant distribution of traffic flow, concerning primary the right lane downstream the exit, and is used for estimation of correction of the downstream access flow, estimation of information about which cars selected for which lane, the road based equipment informing cars selectively about respective allocation of lanes, before or at the latest in stage 2,

and in the second stage, an intermediate lane is implemented, Int., between the two rightest lanes of the motorway, of which the most right one, Ri, at least partly might consist of the earlier implemented exit ramp, and the other, Le, also consists of the left lane of a motorway with two lanes, single direction,

and the said road based equipment is informing cars selectively about respective role, including allocation of lane, during the first or at latest during the second stage, comprising;

cars in Le, which are going to shift to Ri, are informed about the role involving a direct selection of the Int. lane, and after that weaving to the Ri, cars in Ri, which are going to shift to Le, are informed about the role involving weaving to Int. and then further to Le.

4. A method according to claim 1, where the method includes a principal function, HF3, preparatory access control, which concerns traffic control upstream an access, HF3 comprising:

road based equipment, is supplying information to cars on the right lane of the motorway about gap to the car ahead, where the road based information means are positioned on the distance L2 or the distance between the related exit and access, and the gap information is based on the target value of the gap between cars in the right lane of the motorway, based on estimated access flow of cars from downstream access to the motorway,

determination of the target value for the gap according to (a) plus at least one of the following criterias (b) to (e),

(a). the target value shall give a density of cars on the motorway, seen over the corresponding access flow time period, which corresponds to an added total gap, which have room for at least one more car, an access car;

(b). a succession of cars are given the same information, corresponding to equal gaps,

(c). dedication of gaps for cars in a row, where the first one or few first cars are allocated larger gaps than the next followers, and the first cars are selected to match the later weaving by an access car,

(d). the target value is selectively chosen from (b) at large access flows or long distances down to the access, while (c) is selected at smaller access flows or at short distances down to the access weaving zone,

(e). the target value for the gap is dedicated to the car (B) on the motorway, which is selected to let in a car (A) from the access, comprising;

successive detection and registration of cars (A) on the access and cars on the motorway,

prediction of when (A) reach the weaving zone and selection of the car (B) on the motorway, which is predicted to reach the weaving zone next after (A), selective information to (B) about the gap for letting in (A).

5. A method according to claim 1, where the method includes a principal function, HF4, local access control, which concerns control at the local access, HF4 comprising

road based equipment, which detects and registrates cars (A) on the access and cars (B) and (C) on the motorway upstream the access, where the car (B) is the car on the motorway which is going to let in car (A) ahead, and car (C) is following (B), prediction of (A)'"'"'s and (B)'"'"'s travel towards the weaving zone, whereby the selection of (B)-car is based on the said prediction, road based equipment, which upstream the weaving zone, is informing the (B)-car about its role in the weaving, comprising at least one of the following method steps;

(a). informing about the role weaving together with (A) in position upstream (A),

(b). informing about the role carrying out lane-shift to a position behind (A) in the ramp-lane and (B) following (A) to the weaving to the left, i e back into the gap, which (B) left on the motorway,

(c). in addition to (b), informing (C) about the role meaning keeping the gap to car (B), also while (B) is in the parallall lane relative to C.

6. Means for carrying out the methods according to claim 1, concerning systems for access control of traffic at motorways and larger roads, where the access flow is controlled by information means, which directly or indirectly influence the access travel of the cars, and where the flow size is determined considering the flow size on the motorway, and where cars (A) from the access road interact with cars (B, C, etc) on the motorway while weaving together the respective flows, including traffic management system, (TMS), traffic sensors and access equipment, comprising;

a computer based traffic management system being fed with information about flows from various parts of the motorway and its connections to the neighbouring road network, and rations and target values for traffic flows on the accesses and the motorway, being determined and stored with support from the traffic management system, and dynamic corrections being estimated by TMS or by an access equipment, and at least one of (a) and (b) being included;

(a). a sensor being positioned the distance L1 upstream the access weaving zone, measuring the flow continuously and transmitting the traffic information in short time intervals to the TMS and/or the access equipment,

(b). an exit equipment including;

sensors, detecting cars selecting to take off for the exit, a computer unit, being positioned at the exit equipment or at the TMS, computing or predicting the traffic flow in the right lane downstream the exit, and transmitting traffic information in short time intervals to the TMS and/or the access equipment,

an access equipment being positioned at the access, including sensors for traffic measurement and control means for flow control at the access, and rations and correction values are obtained from TMS, or the corrections are estimated from obtained basic values, and the access equipment is managing the corrected access flow,

a computer unit in the TMS, the access equipment or a gap-information system is calculating the target values for gaps for the motorway traffic in the right lane, seen over the access flow time period;

selectively combined with a gap-information system positioned closely upstream the access along the motorway, the gap-information system informing motorway cars about gaps, based on obtained information.

7. Means according to claim 6, concerning information from cars to road based equipment and means, comprising:

an information transfer including at least one of the following information transfers;

(a). the respective blinker of the car for delivering turning information, video sensor for the road based equipment detecting the turning information,

(b) radiowave communication between car and roadbased equipment, including transfer or turning information and supplementary information for identification.

8. Means according to claim 6, for carrying out method steps concerning information from road based equipment to selected cars, comprising:

information transfer with a light-lobe, which is controlled by road based equipment and positioned over the car and/or viewable for the driver on or ahead of the car, and including at least one of the following information transfers;

(a). the light has a selected colour, with a meaning according to given colour code, including identity, of which the following are detailed embodiments of given information in the said claims;

(a1) you are the “

the colour”

,

(a2) you have the “

the role”

,

(a3) you are “

(B)-car”

,

(b), the identity colouris connected to the road based information signs with selective information regarding the corresponding indicated identity colour,

(c). the position of the light-lobe and at least one of shape and colour give information about the controlled gap,

(d) the colour code above is changed to or combined with modulation of the light or infrared “

light”

, which is detected by a car equipment.

9. Means according to claim 6, for carrying out method steps concerning effecting the gap, comprising:

cars equipped with gap controlling equipment, which is fed with information about the gap, and is contributing in effecting the gap.

10. Means according to claim 6, for carrying out method steps concerning prediction or flow control of access traffic, comprising:

cars equipped with speed control equipment, which is used for control of the (A)-car travel plan along the access road, based on information from the road based equipment.

11. Means according to claim 6, for carrying out method steps concerning information from road based equipment selectively to cars along a road, and which means includes presentation means positioned at the side of or above the road, comprising:

selective information is directed to the car concerned; and

is activated, when the car ahead isn'"'"'t seeing the information, and is turned off or changed, when the concerned car no longer is seeing it, and an embodiment is included, where the activity period at dense traffic principally is determined by the respective car passing the information means,

selective information is given by one or more repeated presentation means along the road; and

at repetition;

the content is matched for the respective car travelling from presentation means to presentation means, and whereby information is repeated or successively varied,

selective information is presented in at least one of the following ways (a)-(c);

a. by an individual presentation means,

b. successively, part by part, utilizing a plurality of presentation means,

c. by at least two steps, where the said presentation means information is including an identity information, and where selective additional information is presented by another more general presentation means, which is showing the additional information related to the respective car identity information.

12. Means according to claim 6, comprising:

presentation means presenting selective information, including identifying, according to at least one of;

a. light means, lamps or LED, which are changing colours, or a group of such with different positions and colours, which are switched on in different combinations,

(b). showing different patterns or symbols.

13. Means according to claim 6, which have a task including presenting information about gaps, comprising:

presenting information according to at least one of (a)-(d);

a. gaps are illustrated with symbols, where the real given gap is marked related to the status of the recommended gap, the target gap,

b. increasing gap is illustrated with symbols,

c. static text is indicating gap, and dynamic text or symbols are shown containing the message increase,

d. a static sign positioned upstream the presentation means is informing about those latter means.

14. Means according to claim 6, for carrying out method steps concerning exits, and where the means include road constructions including a section of the motorway with its exit, where the motorway section upstream and downstream is connected to the two right lanes of the motorway, where the lane most to the right is called Ri, and the other Le, comprising:

the motorway section is considered divided into at least three stages;

a first stage, where the two said right lanes, Le and Ri, are separated to give space for a lane in between, Int, where the separation starts with a continuous line, or a corresponding separation between Le and Ri, and the line is following Ri, while Le is branching to a continuous Le and Int, and a dotted line, or corresponding separation, is separating Le from Int, and with a traffic function, in which cars in Le can choose the Int lane directly, while cars in Ri have to wait for weaving into Int, until the continuous line is ended,

a second stage, where the continuous line separating Ri and Int is changed into a dotted line; and

with a traffic function, in which cars from Ri can weave into Int, and later on continue weaving into Le, and cars from Le, now in Int, can weave into Ri, and where Ri is branching to an exit in this stage, or at last in the next (third) stage,

a third stage, where Ri is branched into a branch, which is constituting an exit from the motorway, if this wasn'"'"'t done in stage two, and a branch, which is combined with Int to a lane, which is constituting a continuation of Ri, for connection to the right lane of the motorway, and where the length of the second stage is corresponding to the length of traditional weaving zones, while the other stages can be done shorter, and has the road construction a traffic function, in which cars in respective Le and Ri of the motorway, which want to change lanes, can be performing that in two stages by first changing to an intermediate lane, Int lane, whereby traffic density in Le and Ri are decreasing, and weaving in from Int is simplified, compared with the weaving in dense traffic directly between Le and Ri.