GB2440756A

GB2440756A - A vehicle status and environment based navigation system

Info

Publication number: GB2440756A
Application number: GB0615931A
Authority: GB
Inventors: Kurt Dusterhoff; Jonathan David Ashley
Original assignee: Denso Corp
Current assignee: Denso Corp
Priority date: 2006-08-10
Filing date: 2006-08-10
Publication date: 2008-02-13
Anticipated expiration: 2026-08-10
Also published as: GB0615931D0; GB2440756B

Abstract

A navigation system provides guidance with respect to an instruction point along a route at which an action is required. A guidance point 37 is determined dynamically at which the guidance is to be given for the instruction point 38. A distance Z of the guidance point from the instruction point is determined by modifying a base distance Y by factor representative of vehicle and/or environment status. The guidance point 37 is compared to a current vehicle position determined by a vehicle positioning system. The guidance is output via a user interface in response to determining that the current vehicle position has reached the guidance point Z.

Description

1 2440756

GUIDANCE SYSTEM WITH VARIABLE GUIDANCE TIMING

BACKGROUND

The invention relates to a system for providing guidance information to a user. The user can, for example, be the driver of a vehicle. The system can, for example, be a navigation system.

Conventional guidance systems provide guidance to a user based on predefined characteristics. Some systems provide guidance based on a fixed distance from a point at which an action is required, or other information needs to be imparted to the driver of the vehicle.

As well as providing guidance based on a distance between the vehicle and a guidance point (e.g., a destination, waypoint, junction, etc.), it is also known to provide guidance timing dependent on a current vehicle speed. However, providing guidance on the basis of distance alone, or additionally on the basis of a speed of a vehicle, can only give an approximation of the appropriate timing for the guidance.

Accordingly, an object of the invention is to improve the timing at which guidance instructions are given to a user.

Accordingly, an embodiment of the invention seeks to mitigate at least some of the technical problems discussed above.

SUMMARY

Aspects of the invention are defined in the accompanying claims.

An embodiment of the invention can provide a navigation system for a vehicle operable to provide guidance with respect to an instruction point along a route. The navigation system is operable to determine a guidance point at which the guidance is to be given in respect of the instruction point. A distance of the guidance point from the instruction point is determined by modifying a base distance by factor representative of vehicle status andlor environment status. The guidance point is compared to a current vehicle position determined by a vehicle positioning system ---and a user interface is caused to output the guidance in response to determining that the current vehicle position has reached the guidance point.

An example embodiment of the invention can provide dynamic determination of a guidance point at which guidance for an instruction point (which can be a point by which an action needs to be completed by a driver) in response to a current vehicle position and plural vehicle sensors and/or data sources, whereby audible and/or displayed guidance can be provided at an appropriate timing or position according to current vehicle and/or environment conditions.

A vehicle can be provided that includes a navigation system as described above.

An embodiment of the invention can also provide a method of automatically providing navigation guidance to a driver of a vehicle with respect to an instruction point along a route. The method comprises a navigation system: determining a guidance point at which the guidance is to be given in respect of the instruction point, wherein a distance of the guidance point from the instruction point is determined by modifying a base distance by factor representative of vehicle status and/or environment status; comparing the guidance point to the determined vehicle position to a current vehicle position determined by a positioning system; and causing a user I. 3 interface to output the guidance in response to determining that the current vehicle position has reached the guidance point.

An embodiment of the invention can also provide a computer program product for carrying out the aforementioned method.

Although various aspects of the invention are set out in the accompanying independent claims, other aspects of the invention include any combination of features from the described embodiments andlor the accompanying dependent claims with the features of the independent claims, and not solely the combinations explicitly set out in the accompanying claims. I.

BRIEF DESCRIPTION OF THE FIGURES

Specific embodiments of the present invention will now be described by way of example only with reference to the accompanying Figures in which: Figure 1 is a schematic representation of a vehicle; Figure 2 is a schematic representation of a dashboard of a vehicle; Figure 3 is a schematic representation of a vehicle approaching a guidance point for illustrating the operation of the present invention; Figure 4 is a schematic representation of functional elements of a navigation system for implementing the present invention; Figure 5 is a schematic representation of factors that can be taken into account by the navigation system of Figure 4; and Figure 6 is a flow diagram illustrating an example of the operation of the navigation system of Figure 4.

While the invention is susceptible to various modifications and alternative forms, specific embodiments are shown by way of example in the drawings and are herein described in detail. It should be understood, however, that drawings and detailed description thereto are not intended to limit the invention to the particular form disclosed, but on the contrary, the invention is to cover all modifications, equivalents and alternatives falling within the spirit and scope of the present invention as defined by the appended claims.

DESCRIPTION OF EMBOD[MENTS

Figure 1 a schematic representation of a vehicle 10 provided with a satellite antenna 12 for receiving satellite signals for use in a navigation system. The navigation system can include one or more of a satellite positioning system, for example a Global Positioning System (GPS), and a dead reckoning system, for example for use in built up areas.

Figure 2 is a schematic representation of a dashboard 20 of a vehicle such as the vehicle 1. Among other components illustrated on the dashboard are a display screen 22 of a navigation system, for example a touch screen display, and a loudspeaker 54.

These components will be referred to in the following description.

Figure 3 is a schematic representation of a vehicle 35 approaching an instruction point 38 (for example a point by which an action needs to be completed by a driver), for example for following a route 32 on which the vehicle 35 is travelling. The instruction point 38 can, for example, be a destination point, a waypoint, a junction, or the like. As illustrated in Figure 3, the vehicle 35 is at a position 36 at a distance Y from the instruction point 38. The navigation system is operable to provide instruction to the driver of the vehicle 35 at a guidance point 37 which is a distance Z from the instruction point 38. In an example embodiment, the distance Z and therefore the position and/or the timing of the guidance point 37 are varied depending on a number of conditions as will be described in the following.

The timing of the guidance, and therefore the guidance point can be chosen according to the manner of the guidance given. For example if the guidance includes voiced guidance, then the timing of the start of the guidance is chosen so that it is complete by a time that the vehicle driver can react to the guidance prior to the instruction point. If the guidance is provided by a displayed guidance, then the timing of the giving of the guidance can be adapted accordingly to allow for the driver to react to the displayed guidance information. I.

Figure 3 also illustrates a further vehicle 33 at a position 34 located at a distance X from the vehicle 35.

The representation in Figure 3 illustrates a situation at a given point in time as the vehicle 35 travels along a route 32 on which the instruction point 38 is located.

Figure 4 is a schematic representation of an example embodiment of a navigation system. The navigation system 40 includes a positioning system 42 which is responsive to signals from the satellite antenna 12 to determine the current location of the vehicle. As indicated above, the positioning system 42 can be a GPS system, but could be based additionally or alternatively on one or more other types of positioning determining systems, for example a dead reckoning system. A processor 46 is responsive to the position determined by the positioning system 42 to perform navigation computations. The processor 46 can be configured as a special purpose processor, or a general purpose processor responsive to program instructions held in storage 44 and/or working memory 48.

As described in the following, the processor 46 can be responsive to sensors 52 and 56 which can involve vehicle condition sensors 52 and environment sensors 56. The processor can be operable to provide instruction to the user at a guidance point through the use of the display 22 and/or audible instruction via a loudspeaker 54 which can be part of the audio and/or audiovisual system of the vehicle 10.

In an embodiment of the invention, the navigation system 40 is responsive to a plurality of parameters indicative of the vehicle condition and/or the environment to determine appropriate factors for adjusting a base distance for providing an instruction to a user.

Table I below illustrates typical stopping distances (based on values of the UK Highway Code to be found at http://www.highwaycode.gov.uk) to include a thinking distance, braking distance and total distance. Examples of minimum advised distances for good driving conditions indicative of safe responsible driving could, for I. example, be based on these stopping distances and/or on a multiple of these stopping distances andlor on other stopping distances as appropriate.

TABLE 1

Speed Thinking Distance Braking Distance Total Distance 32KPH 6m 6m 12m 48 KPH 9m 14m 23m 64 KPH 12m 24m 36m 8OKPH 15m 38m 53m 9âKPH 18m 55m 73m I12KPH 21m 75m 96m > 112 KPH

S

Figure 5 is a schematic representation of various sensors and/or conditions that may be used to vary the timing of the guidance point referred to above.

A base distance can be determined in accordance with vehicle configuration information V dependent on a particular vehicle type and/or model. The vehicle type could, for example, trigger the use of high, medium and low distance vehicle definitions. High distance vehicles could include very heavy vehicles and high-performance sports vehicles. Medium distance vehicles could include vehicles with difficult visibility (e.g., some forms of 4x4 vehicles and mini-vans). Low distance vehicles could include general use vehicles that make up the majority of vehicles on the road. The base distance and or timing for the different categories can reflect basic differences in typical stopping distances.

Further information can be detennined based on a sensor A related to the vehicle mirrors, for example to indicate whether an auto dimming facility is activated due to driving at night and/or with a vehicle close behind. Similarly, radar sensors B can be operative to determine the proximity of a further vehicle. Weather information C can be provided, for example, in response to determining the operation of sensors such as a rain sensor H or wipers F, or information provided via telemetry, radio, mobile telephony, etc. A speed sensor D can be responsive to the current speed of a vehicle.

A light sensor E can be responsive to the operation of lights to determine whether the vehicle is driving in adverse weather conditions andlor at night. As mentioned above, the state of the wipers F can be used to determine whether the vehicle is driving in wet conditions. The clock G of the vehicle can be used to determine whether the driver is driving at night when reaction times may, for example, be slower. As mentioned above, a rain sensor H can be used to determine whether the vehicle is driving in rain. A thermometer I can be used to determine whether the vehicle is driving in cold conditions when there is a risk, for example, of ice or snow, or very warm conditions where the parameters of a tyre and/or road surface may be affected.

The navigation system can be operable to provide road class information J, for example whether the road is a major road, a minor road, dual or single carriageway, etc. Other parameters and/or sensors K can be used to determine various functions, such as, excessive suspension movement indicative of a poor road surface, measurement of reflectivity of a road to determine how much grip is available through the road surface, sensors adapted to detect eye movement of the user, indicative of a potential that a user is tired. Similarly, detection of unusual steering input and/or sluggish responsiveness of the user could be used to indicate potential tiredness of the driver, etc. As represented in Figure 5, data in respect of these various parameters can be provided to the navigation system 40 to derive factors for determining a distance from the instruction point to the guidance point at which guidance is to be given based on the base distance representative of the vehicle configuration V and the various additional input parameters. In a given instance, a selection of additional input parameters may be used, depending on a particular implementation.

The data representative of the parameters can in some cases be provided directly to the navigation system. Other data can be stored in memory or storage (e.g., the memory 48 or the storage 44), for example by other vehicle systems andJor in response to received telemetry or navigation data and can then be accessed by the navigation system processor.

In other words, the navigation system can be operable to respond to sensor data from at least one sensor operable to detect a vehicle status parameter and/or to obtain stored data representative of a vehicle status parameter. The vehicle status parameter can be representative of one or more of, for example: a vehicle speed status; a vehicle clock time; a vehicle condition status; a volume of audio status; an audio type (such as music, news, radio, CD, etc.); a status of a hands free function; a status of an adaptive cruise control system; a passenger type (such as baby on board or not), etc. The navigation system can alternatively, or additionally, be operable to respond to sensor data from at least one sensor operable sense an environment parameter and/or to obtain stored data representative of at least one environment parameter. Examples of a sensor that can be operable to sense an environment parameter include a moisture sensor, a wiper status sensor, a vehicle mirror auto-dim sensor; an external proximity sensor; a vehicle light status sensor; a brake system sensor, for example an anti-lock brake system sensor, a suspension system sensor, etc. An environment parameter can be representative of, for example, an external temperature, a wetness (e.g., how much moisture is detected by a moisture sensor), an ambient light level, a vehicle proximity, a road surface condition, etc. The stored data representative of an environment parameter can, for example be derived from navigation data. The stored data derived from navigation data can include, for example, one or more of road type, local speed limit, road inclination.

In an example embodiment of the invention, different parameters can be employed in the calculation with different scaling factors. Some examples of suitable scaling factors are set out in the following examples. These weightings are merely examples, and the scaling factors in a particular implementation can be selected appropriately.

The current speed could prime a basic time/distance calculation where faster moving vehicles produce guidance earlier to allow sufficient manoeuvring time. The road classification can determine if the user is likely to have one lane or multiple lanes of traffic to account for in the manoeuvre. Wet or extremely hot conditions could require the distance to be multiplied by a factor of two. Freezing conditions could w.

require a further trebling of the distance. The additional factors such as darkness (detected from the clock and/or headlamp status), following traffic (detecting using auto-dimming mirror and/or other sensors) could entail a further multiplier (e.g., 1.25) to allow for other road users to react to the drivefs reactions. It will be appreciated that these multiplication factors are given by way of example only, and that other multiplication factors could be used as appropriate for a given implementation.

In the following, two illustrative examples will be given.

Example I is a high performance 4x4 vehicle with high performance ceramic brakes travelling on a clear, warm night on a single carriageway road at 100 kilometres per hour. There is a car 10 metres behind. The destination is 200 metres ahead.

A base high performance guidance distance is set at 200 metres. Various weightings can be applied to this as follows: High performance brakes = 0.9 Night-time = 1.4 High speed = 1.0 Dry weather = 0.7 Close behind car = 1.2 Warm weather = 0.7 Windows down = 0.8 Steep downward gradient = 1.3 Applying the above mentioned factors to the high performance vehicle base guidance distance of 200 metres results in a final distance of 144 metres. Accordingly, the guidance warning about the nearby destination would be played at 144 metres before the destination.

Example 2 is a high performance 4x4 vehicle with high performance ceramic brakes travelling on a clear, warm night on a single carriageway road at 50 kilometres per hour. There is a vehicle 10 metres behind. The destination is 100 metres ahead.

As indicated above, the high performance vehicle base guidance distance is 200 metres. The weighting applied to the calculation is as follows: High performance brakes = 0.9 Night-time = 1.4 Low speed = 0.3 Dry weather = 0.7 Close behind car = 1.2 Warm weather = 0.7 Windows down = 0.8 Steep downward gradient = 1.3 Applying the above mentioned factors to the high performance vehicle base guidance distance of 200 metres results in a final distance of 46 metres. Accordingly, in this example, the guidance warning about the nearby destination will be played 46 metres before the destination.

If the guidance distance is greater than the actual distance to a guidance point, the user can be notified that they are at, or near, or past the guidance point. The rates can be chosen so that the user can be given notification that fits the vehicle and condition, rather than being the same for all users all the time. This enables more accurate response timing to be given to the driver to enable the driver to manoeuvre responsibly and safely on the road.

The user interface used to output the guidance in response to the processing system determining that the current vehicle position is at or past the guidance point can, for example, provide audio and/or visual guidance. Audio guidance can be given, for example by the vehicles audio system. Visual guidance can be given, for example, via the navigation display screen.

Figure 6 is a flow diagram illustrating an example of operation of the guidance system based on the above.

Step 62 is indicative of a current position of the vehicle being determined by the navigation system.

At a given time or interval, the current position is compared at step 66 to a next instruction point along the route of the vehicle and a determination is made whether the current position is at, for example, 300%, 200%, 100% or 50% of a base distance (step 64) away from the instruction point.

If, as a result of the comparison at step 66 it is determined that the vehicle is at one of the given multiples of the base distance from the instruction point, then following step 68, in step 70, the guidance point is determined at which guidance will be played.

If in step 68 it is determined that the comparison does not indicate that the current position is at a given guidance point, then the comparison at step 66 is performed for successive current position determinations 62 made by the navigation system 40.

Step 72 is representative of the guidance point being determined and stored in the memory 48 of the navigation system.

In step 74, the guidance point is compared to the current position 62. The comparison is performed repeatedly, as represented by the decision point 76, until the guidance point is determined to have been reached by the current position.

In response to determining that the current position is equal or greater than the guidance point (i.e. the guidance point has been reached), then at step 78 appropriate the guidance or instruction is output to the user.

If it is determined in step 76 that the guidance point has not only been reached but has also been passed (e.g., where a change in the sensed conditions has occurred), then rather than the normal guidance, guidance including a warning that the guidance point has been passed can be given to the user in step 78.

Accordingly, there has been described a navigation system that can provide dynamic adjustment of a point at which guidance is given with respect to an instruction point along a route at which an action is required. A processing system dynamically determines the guidance point at which the guidance is to be given for the instruction point. A distance of the guidance point from the instruction point is determined by modifying a base distance by factor representative of vehicle and/or environment status. The guidance point is compared to a current vehicle position determined by a vehicle positioning system. The guidance is output via a user interface in response to determining that the current vehicle position is at or past the guidance point.

A computer program product for implementing the invention can be in the form of a computer program on a carrier medium. The carrier medium could be a storage medium, such as a solid state, magnetic, optical, magneto-optical or other storage medium. The carrier medium could be a transmission medium such as broadcast, telephonic, computer network, wired, wireless, electrical, electromagnetic, optical or indeed any other transmission medium.

Although the embodiments above have been described in considerable detail, numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications as well as their equivalents.

Claims

CLAIMS

1. A navigation system for a vehicle operable to provide guidance with respect to an instruction point along a route, wherein the navigation system is operable: to determine a guidance point at which the guidance is to be given in respect of the instruction point, wherein a distance of the guidance point from the instruction point is determined by modifying a base distance by factor representative of vehicle status andlor environment status; to compare the guidance point to a current vehicle position determined by a vehicle positioning system; and to cause a user interface to output the guidance in response to determining that the current vehicle position has reached the guidance point.

2. The navigation system of claim 1, operable to respond to sensor data from at least one sensor operable to detect a vehicle status parameter for modifying the base distance by a vehicle status factor.

3. The navigation system of claim I or claim 2, operable to obtain stored data representative of a vehicle status parameter for modifying the base distance by a vehicle status factor.

4. The navigation system of claim 2 or claim 3, wherein the vehicle status parameter is representative of one or more of: a vehicle speed status; a vehicle clock time, a vehicle condition status.

5. The navigation system of any one of the preceding claims, operable to respond to sensor data from at least one sensor operable to sense an environment parameter for modifying the base distance by an environment factor.

6. The navigation system of claim 5, wherein the at least one sensor that is operable to sense an environment parameter is one or more of: a moisture sensor, a

-S

wiper status sensor, a vehicle mirror auto-dim sensor; an external proximity sensor; a vehicle light status sensor; a brake system sensor, a suspension system sensor.

7. The navigation system of any one of the preceding claims, operable to obtain stored data representative of at least one environment parameter for modifying the base distance by an environment status factor.

8. The navigation system of any one of claims 5 to 7, wherein a said environment parameter is representative of one of an external temperature, a wetness, an ambient light level, a vehicle proximity, a road surface condition.

9. The navigation system of claim 7, wherein the stored data representative of an environment parameter is derived from navigation data.

10. The navigation system of claim 9, wherein the stored data derived from navigation data includes one or more of road type, local speed limit, road inclination.

11. The navigation system of any one of the preceding claims, wherein the base distance is determined according to a vehicle type.

12. The navigation system of any one of the preceding claims, further comprising the user interface operable to output the guidance in response to the processing system determining that the current vehicle position has reached the guidance point.

13. The navigation system of any one of the preceding claims, wherein the user interface is operable to at least one of audible or displayed guidance.

14. The navigation system of any one of the preceding claims, further comprising the vehicle positioning system operable to determine a current vehicle position.

15. A vehicle comprising a navigation system as claimed in any one of the preceding claims.

16. A method of automatically providing navigation guidance to a driver of a vehicle with respect to an instruction point along a route, the method comprising a navigation system: determining a guidance point at which the guidance is to be given in respect of the instruction point, wherein a distance of the guidance point from the instruction point is determined by modifying a base distance by factor representative of vehicle status and/or environment status; comparing the guidance point to the determined vehicle position to a current vehicle position determined by a positioning system; and causing a user interface to output the guidance in response to determining that the current vehicle position has reached the guidance point.

17. The method of claim 16, wherein the navigation system responds to sensor data from at least one sensor detecting a vehicle status parameter for modifying the base distance by a vehicle status factor.

18. The method of claim 16 or claim 17, comprising the navigation system obtaining data from memory representative of a vehicle status parameter for modifying the base distance by a vehicle status factor.

19. The method of claim 17 or claim 18, wherein the vehicle status parameter is representative of one or more of: a vehicle speed status; a vehicle clock time, a vehicle condition status.

20. The method of any one of claims 16 to 19, wherein the navigation system responds to sensor data from at least one sensor operable determine an environment parameter for modifying the base distance by an environment factor.

21. The method of claim 20, wherein the at least one sensor that determines an environment parameter is one or more of: a moisture sensor, a wiper status sensor, a

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vehicle mirror auto-dim sensor; an external proximity status; a vehicle light status sensor; a brake system sensor, a suspension system sensor.

22. The method of any one of claims 16 to 21, wherein the navigation system obtains stored data representative of at least one environment parameter for modifying the base distance by an environment status factor.

23. The method of any one of claims 20 to 22, wherein a said environment parameter is representative of one of an external temperature, a wetness, an ambient light level, a vehicle proximity, a road surface condition.

24. The method of claim 23, wherein the stored data representative of an environment parameter is derived from navigation data.

25. The method of claim 24, wherein the stored data derived from navigation data includes one or more of road type, local speed limit, road inclination.

26. The method of any one of claims 16 to 25, wherein the base distance is determined according to a vehicle type.

27. The method of any one of claims 16 to 26, wherein the user interface outputs at least one of audible or displayed guidance.

28. A navigation system substantially as hereinbefore described with reference to the accompanying claims.

29. A method of automatically providing navigation guidance to a driver of a vehicle substantially as hereinbefore described with reference to the accompanying claims.

30. A computer program product comprising program code operable to control a navigation system to carry out the method of any one of claims 16 to 27 and 29.