WO2009116866A2

WO2009116866A2 - Navigation device

Info

Publication number: WO2009116866A2
Application number: PCT/NL2009/050131
Authority: WO
Inventors: Martin Bruin; Robert Bieling; Ernst Verbeek; Davy Henri Barend Doorenbosch; Van Der Paulus Antonius Willebrordus Leonardus Linden; Manfred Dalmeijer
Original assignee: Falkplan Andes Holding Bv
Priority date: 2008-03-20
Filing date: 2009-03-19
Publication date: 2009-09-24
Also published as: NL2001394C2; WO2009116866A3

Abstract

A navigation device for a vehicle, comprising a processor unit, memory means, data input means, a sound and/or image output unit, wherein said memory means comprise a database with data representing a network of nodes and links between said nodes, wherein said processor unit is arranged to determine a quick and/or short route via links between nodes from a location in the network to a destination location in the network, which has been input by means of the data input means, and to give a driver of the vehicle directions by means of said sound and/or image output unit to reach the destination location via the determined route, wherein said database further comprises collections of nodes and links which define at least one preferred route, which preferred route may differ from the fast and/or short route between the nodes that the processor unit would calculate, and wherein said processor unit is arranged to substitute a route segment between two locations - if the calculated route has at least said two different locations in common with a segment of a preferred route that has no overlap with the calculate route - for the segment of the preferred route that connects said two locations.

Description

NAVIGATION DEVICE

The invention relates to a navigation device for a vehicle, comprising a processor unit, memory means, data input means, a sound and/or image output unit, said memory means comprising a database with data representing a network of nodes and links between said nodes, said processor unit being arranged to determine a quick and/or short route via links between nodes from a location in the network to a destination location in the network, which has been input by means of the data input means, and to give a driver of the vehicle directions by means of said sound and/or image output unit to reach the destination location via the determined route.

A side effect of the growing market for navigation systems is that an increasing number of road users, who follow a navigation system's directions, can no longer be directed in the traditional way by road operators via signposts. The routes defined by navigation systems are often quite different from the circulation routes planned and desired by the road operators. This leads to traffic at unwanted locations {also called GPS rat-run traffic) straight through residential areas, school areas or village centres.

Navigation systems use a geographic database, in which roads and streets are stored. The roads and streets have varying characteristics (road classifications) , such as the allowed speed, one-way traffic, etc. To have road users take main routes as much as possible within built-up areas, a number of distinctive characteristics are added, such as a main route or a district opening road. A route is determined by inputting a destination. The starting point is determined by means of a positioning system, such as GPS. The routing software subsequently calculates a route on the basis of a mathematical algorithm. If the fastest route is desired, the allowed speeds on the roads and streets between starting point and destination are the main criterion on the basis of which the routing software determines the route. Criteria in the routing software are, for example: finding the fastest route, avoiding motorways or calling at intermediate destinations. The current view is that the addition of characteristics and criteria will enable the routing software to produce a better route advice. However, this does by no means in all cases lead to the result desired by road operators.

The object of the invention is to solve the above problem in an efficient, simple and effective manner.

In order to accomplish that object, the database further comprises collections of nodes and links which define at least one preferred route, which preferred route may differ from the fast and/or short route between the nodes that the processor unit would calculate, said processor unit being arranged to substitute a route segment between two locations - if the calculated route has at least said two different locations in common with a segment of a preferred route that has no overlap with the calculate route - for the segment of the preferred route that connects said two locations. The preferred routes may be defined by road operators, for example comprising existing through routes for cars and/or trucks indicated by signposts. In this way the algorithm will automatically substitute the segment of the route originally calculated by the navigation system that extends between two points on a preferred route for the segment of the preferred route that extends between said two points .

The processor unit is preferably arranged to determine - if a particular route segment has been substituted for a segment of a preferred route - whether the route determined in that case has at least two different locations in common with a segment of a preferred route that has no overlap with the determined route, and to substitute the determined route segment between the two locations for the segment of said preferred route that connects the two locations, and to repeat said step each time route segments have been substituted in said step. In this way drivers are directed along preferred routes as much as possible in an iterative process, insofar as this is necessary.

The memory means preferably comprise several defined preferred routes for at least one class of vehicles and/or at least one time window, the processor unit being arranged to substitute particular route segments for segments of preferred routes only if the vehicle class stored in the memory means corresponds to the vehicle class and the time window for the preferred route in question. In this way road operators can have preferred routes for different categories of vehicles and different time windows defined in the navigation system, as is currently frequently indicated on signposts. The vehicle classes preferably comprise at least one class of heavy goo'ds vehicle traffic or hazardous materials vehicle traffic and the time windows preferably comprise at least one time window for rush hours.

The invention further relates to a data carrier with a computer programme comprising the instructions required for arranging the processor unit in the manner described above. The invention also relates to a data carrier with a database comprising collections of nodes and links which define at least one preferred route intended for use in the navigation device as described in the foregoing. The invention also relates to a method for distributing a computer programme, wherein a computer programme comprising the instructions required for arranging the processor unit as described above is provided via a network or a data carrier and is input into the memory means of the navigation device. The invention also relates to a method for distributing data, wherein a database comprising collections of nodes and links defining at least one preferred route is provided via a network or a data carrier and is input into the memory means of the navigation device as described in the foregoing.

The invention will now be explained in more detail with reference to embodiments shown in the figures, in which:

Figures IA, IB and 1C show examples of the substitution of a sub route in a representation of a road network;

Figure 2 shows an example of a route through various "clusters" in a road network; and

Figure 3 shows a simplified representation of part of a road network.

The navigation device comprises a housing containing, among other components, a central processor unit, permanent memory means such as a hard disk or a flash memory, volatile memory means such as RAM, an input unit such as a keyboard or an LCD touchscreen, and a sound output unit such as a loudspeaker. The components of the navigation device are interconnected in a known manner and can cooperate for executing a computer programme in a manner that is known per se. The memory means comprise a geographic database with nodes and links between said nodes, which jointly represent a network, and a computer programme by means of which the processor unit can calculate an initial fastest or shortest route between a starting node and a destination node by means of a navigation algorithm.

The present navigation device provides an additional component in the geographic database, as well as an adaptation of the navigation algorithm.

In addition to the aforesaid data, the geographic database of the navigation device comprises starting and destination nodes of preferred routes, which can be defined by interested parties, such as road operators. Preferred routes are defined between said starting and destination nodes, which routes may run via intermediate nodes. The preferred routes may be different for each transport modality (for example passenger car or truck) and may for example be defined for specific time windows. Furthermore, preferred routes may be unidirectional as well as bidirectional .

Preferred routes are stored in a supplier-neutral format by which they can be projected on various road network databases. Existing techniques, such as TMC or Agora, can be used for this purpose.

Distribution to route planners and navigation systems can take place offline (for example over the Internet or by CDROM) as well as online and in real time (GPRS, UMTS) . In the case of real time distribution, temporary relief routes can be passed on in situations as they occur, such as incidents (accident, disaster) . The algorithm can deal with preferred routes as a fixed route between the starting point and the destination, but also as a collection of starting points/destinations between each of the nodes within the preferred route. In that case all the traffic that arrives or leaves halfway the preferred route is directed by means of a preferred route as well.

The navigation algorithm of the navigation device calculates the route from the starting point to the destination, but it substitutes segments of the originally calculated route for segments of one or more preferred routes. The phrase "segment of a preferred route" is understood to mean a segment of the preferred route between two nodes of said preferred route, which nodes are not necessarily the starting node and the destination node.

Figure 1 shows three examples of the substitution of a route segment in a representation of a node database.

Figure IA is an example in which the clock time of the navigation device is 8.00 a.m. and the traffic modality input into the navigation device by the user is "passenger car". The route (I) between the starting node S and the destination node E as initially calculated by the processor unit is S - A - D - E. As the database does not comprise a preferred route having at least two nodes "in common with the initially calculated route for this modality at this point in time, no substitution of calculated route segments will take place, and the finally calculated route

(F) is likewise S - A - D - E.

Figure IB is an example in which the clock time of the navigation device is 9.00 a.m. and the traffic modality input into the navigation device by the user is "truck". The route between starting node S and destination node E initially calculated by the processor unit is S - A - D - E. Since a preferred route A

- B - C - D having the nodes A and D in common with the initially calculated route is defined in the database for this modality at this point in time, and the two routes are different from each other, a substitution of the calculated route segment A - D between these nodes for the segment A-B -C- D of the preferred route takes place, with the finally calculated route being S - A - B - C - D - E.

Figure 1C is an example in which the clock time of the navigation device is 9.00 a.m. and the traffic modality input into the navigation device by the user is "truck" . The route between starting node S and destination node E initially calculated by the processor unit is S - B - A - D - E. Since a preferred route A - B - C - D having the nodes A, B and D in common with the initially calculated route is defined in the database for this modality at this point in time, and the routes are different from each other, a substitution of a segment of the calculated route for a segment of the preferred route takes place. Two final routes are possible in that case; substitution of A - D for A - B - C

- D with final route S - B - A - B - C - D - E, and substitution of B - A - D for B - C - D with final route S - B - C - D - E. From these two options, the shortest route is determined, with the finally calculated route being S - B - C - D - E.

In figure 2 an example is given of a longer route through various "clusters". Preferred routes are Bl-Al-Dl-El, B2-C2-F2-I2-H2, and B3-A3-D3-G3-H3. The calculation of the route and the substitution for segments of preferred routes takes place in real time, in dependence on the point in time at which the vehicle arrives at the cluster in question. Figure 3 shows a strongly simplified representation of part of a road network. The table below includes the network segments between two sets of nodes:

Routes are recorded as sequences of nodes, for example: from A to C via B.

Preferred routes are represented as follows in tabular form:

For example, if the initially calculated route X - A - B - C - Z has been calculated for a car at 10:00, a preferred route A - D - C between A and C has been determined for that modality at that point in time.

The algorithm that generates the desired routes can for example proceed as follows {several variations for the exact implementation are possible, which variations all produce the same result:

1. The initially, conventionally calculated route is the starting point. It is called the working route.

2. Determine which preferred routes have an overlap (common nodes) with the working route. Ignore the other preferred routes.

3. Start with the first node of the working route (in this case

X) .

4. Determine for all combinations from x to all the other nodes whether a preferred route exists. Start with the longest mathematical routes: a. X - Z b. Z - C

C. X - B d. X - A

5. Check for each of said route segments whether it corresponds with the starting node and the destination node of a preferred route. There are no common starting and destination nodes in that case. 6. Move the starting node one position ahead (it will be A now, therefore) . Repeat from step 4. The second iteration thus leads to the following route segments: a. A - Z b. A - C

Route segment A - C has starting and destination nodes in common met preferred route A - D - C. Substitute route segment A - C for preferred route A - D - C. This will lead to the following working route: X - A - D - C - Z.

7. Return to step 2 with this adapted working route. In this way "preferred routes within preferred routes" can be substituted in the algorithm.

Once all combinations have been gone through, the result is the following final route: X - A - D - C - Z.

It is also possible to regard each preferred route as a series of implicit preferred route segments. The preferred route A - D - C can for example be regarded as the following implicit preferred routes:

1. A - D - C

2. A - D

3. D - C

If in the above example a car drives from y to z, the initially determined route is: Y - D - B - C - Z. Of the aforesaid route segments, segment D - C has corresponding starting and destination nodes. By substituting this in the working route, the following final route is obtained: Y-D-C-Z. This function can be programmed in the above step 4 of the algorithm in a simple manner.

Claims

CIAXMS

1. A navigation device for a vehicle, comprising a processor unit, memory means, data input means, a sound and/or image output unit, wherein said memory means comprise a database with data representing a network of nodes and links between said nodes, wherein said processor unit is arranged to determine a quick and/or short route via links between nodes from a location in the network to a destination location in the network, which has been input by means of the data input means, and to give a driver of the vehicle directions by means of said sound and/or image output unit to reach the destination location via the determined route, wherein said database further comprises collections of nodes and links which define at least one preferred route, which preferred route may differ from the fast and/or short route between the nodes that the processor unit would calculate, and wherein said processor unit is arranged to substitute a route segment between two locations - if the calculated route has at least said two different locations in common with a segment of a preferred route that has no overlap with the calculate route - for the segment of the preferred route that connects said two locations.

2. A navigation device according to claim 1, wherein the processor unit is arranged to determine - if a particular route segment has been substituted for a segment of a preferred route - whether the route determined in that case has at least two different locations in common with a segment of a preferred route that has no overlap with the determined route, and to substitute the determined route segment between the two locations for the segment of said preferred route that connects the two locations, and to repeat said step each time route segments have been substituted in said step.

3. A navigation device according to claim 1 or 2, wherein the memory means comprise several defined preferred routes for at least one class of vehicles and/or at least one time window, the processor unit being arranged to substitute particular route segments for segments of preferred routes only if the vehicle class stored in the memory means corresponds to the vehicle class and the time window for the preferred route in question.

4. A navigation device according to claim 3, wherein the vehicle classes comprise at least one class of heavy goods vehicle traffic or hazardous materials vehicle traffic.

5. A navigation device according to claim 3 or 4, wherein the time windows comprise at least one time window for rush hours.

6. A data carrier with a computer programme for a navigation device, which comprises the instructions required for arranging the processor unit as defined in any one of the preceding claims.

7. A data carrier with a database for a navigation device, which comprises collections of nodes and links which define at least one preferred route intended for use in the navigation device according to any one of the preceding claims.

8. A method for distributing a computer programme, wherein a computer programme comprising the instructions required for arranging the processor unit as defined in any one of the preceding claims is provided via a network or a data carrier and is input into the memory means of the navigation device according to said claim.

9. A method for distributing data for use in a navigation system, wherein a database comprising collections of nodes and links defining at least one preferred route is provided via a network or a data carrier and is input into the memory means of the navigation device according to any one of the preceding claims.