WO2011078748A1

WO2011078748A1 - Driver notification system and method

Info

Publication number: WO2011078748A1
Application number: PCT/SE2009/000534
Authority: WO
Inventors: Carl Fredrik Mannerfelt
Original assignee: Volvo Lastvagnar Ab
Priority date: 2009-12-22
Filing date: 2009-12-22
Publication date: 2011-06-30

Abstract

The present invention relates to a driver notification system comprising a driver indicator for notifying a driver during operation of a vehicle, wherein driver indicator is connected to a control unit. The control unit is configured to control the driver indicator to notify the driver to activate a cruise control if a set of cruise control conditions are fulfilled, wherein the set of cruise control conditions comprises that the vehicle has a speed above, or coinciding, with a predetermined vehicle speed value, and that a mechanical transmission of the vehicle is operated in a predetermined gear value. The present invention further relates to a method for notifying a driver to activate cruise control during operation of a cruise control equipped vehicle.

Description

DRIVER NOTIFICATION SYSTEM AND METHOD Field of the Invention

The present invention relates to a driver notification system comprising a driver indicator for notifying a driver during operation of a vehicle, such as a heavy truck, or a car, wherein the driver indicator is connected to a control unit. The present invention also relates to a method for notifying the driver during operation of a cruise control equipped vehicle. Background Art

For a driver operating a vehicle, such as a truck, car, or other road vehicle, it is often suitable to activate a cruise control function of the vehicle. The cruise control function is arranged to automatically control the speed of the vehicle when activated, and is typically used to maintain a substantially constant speed of the vehicle. Especially during long haul transport, or long drives, wherein the vehicle is driven long distances and the driver is driving under relatively stationary driving conditions, the cruise control function may allow for an improved fuel economy. For example, the cruise control may allow for a reduction of negative effects associated with the personal driving style of the driver.

WO 2008/082403 describes a cruise control system which permits the driver to set a plurality of cruise control speed settings. In more detail, the cruise control system comprises a speed control mechanism for maintaining a speed of a vehicle at a selected one of a plurality of preset speed settings.

Conventional vehicles and vehicle systems involving a cruise control function, however, are disadvantageous in that the driver, during operation of the vehicle does not activate the cruise control or does not remember to activate the cruise control, which, in turn, may lead to increased fuel economy and undesired driver behavior. Summary of the Invention

The object of the present invention is to improve fuel economy and the personal driving style behavior of the driver of a vehicle.

These and other objects are met by the subject matter provided in the independent claims. Preferred embodiments of the invention are presented in the dependent claims.

According to a first aspect thereof, the present invention relates to a driver notification system comprising a driver indicator for notifying a driver during operation of a vehicle. Furthermore, the driver indicator is connected to a control unit. The control unit is configured to control the driver indicator to notify the driver to activate a cruise control if a set of cruise control conditions are simultaneously fulfilled, wherein the set of cruise control conditions comprises a first condition that the vehicle has a speed above, or coinciding, with a predetermined, or preset, vehicle speed value, and a second condition that a mechanical transmission, or a gearbox, of the vehicle is operated in a predetermined, or preset, gear value, or set of gears, or operated above the predetermined gear value.

Improved fuel economy and improved operation of the vehicle is facilitated and achieved by providing a driver notification system which is arranged to notify the driver to activate the cruise control function during suitable conditions. In other words, a driver support system wherein the driver notification system coaches the driver in order to improve the driving and the driver's operation of the vehicle, is achieved. In particular, the driver notification system is arranged to notify the driver to activate the cruise control when the vehicle is operated in conditions that are suitable and safe for cruise control, such as during long drives on a major road with relatively stationary driving conditions, which may be compared to driving on smaller roads, or bypaths, in urban areas. Also, the driver notification system provides vehicle operating information which may be utilized for evaluating and affecting the personal driver behavior of the driver.

The invention is further advantageous in that the driver is coached, or affected, to utilize the functionality of the cruise control which lead to that the driver more often and more quickly activates the cruise control when it is suitable to do so. Thus, the vehicle may be operated by the cruise control in more stationary and optimized driving conditions. For example, the vehicle speed value and vehicle operating gear value may be optimized such that the driver notification system notifies the driver when optimized speed and gear conditions are present. Hence, efficient and optimized vehicle operation and driving is facilitated. For example, efficient and/or optimal gear conditions, or gear selection, correspond efficient power transfer in the mechanical transmission with little losses due to gear interactions, such as gear meshing under load, vibrations, and that as transmission is operated with a low number of rotating parts.

The predetermined vehicle speed value, as defined in the first cruise control condition, may for example be above 30 km/h preferably above about 50 km/h, more preferably above about 75 km/h. Also, the predetermined vehicle speed value may be between 30 km/h and 1 10 km/h, preferably between 45 km/h and 100 km/h, more preferably between 80 km/h and 95 km/h. The vehicle speed value may be set by the driver during, or before, operating of the vehicle, but may also be set remotely by a specific

instruments, tools, or wireless devices.

The predetermined gear value, as defined in the second cruise control condition may be a preset gear, or speed, of the transmission. The gear value may also comprise a plurality of suitable gears/speeds. For example, the gear value may be predetermined such that a gear which provides efficient fuel consumption and power efficiency is utilized. Also, the predetermined gear value may comprise a set of suitable gears, or transmission gear ratios.

Furthermore, the vehicle gear value may e.g. comprise the highest three gears, the highest two gears, or the highest gear of the transmission.

The transmission, or gearbox, of the vehicle may for example be a manually operated transmission, automatic or semi-automatic transmission, or a manually initiated transmission. Furthermore, in the case of an automatic or continuous transmission, the vehicle gear value may be defined as the gear ratio, or the rotation ratio, between the rotation of the drive shaft and the engine shaft of the vehicle. The transmission, such as for a heavy vehicle, may also comprise a main portion, main and range portions, or main, range and split portions. In other words, the transmission may be equipped with split gear and range gear.

By being fulfilled simultaneously, the cruise control conditions are fulfilled essentially at the same time. However, the control unit may for example be configured to evaluate the first and second conditions essentially simultaneously in a driving situation. This implies that the cruise control conditions may be simultaneously fulfilled if the control unit, in a driving situation, first evaluates the first condition and then evaluates the second conditions, wherein the evaluations are performed essentially after each other such that the same driving situation is the same. The control unit may also first evaluate, or determine, the second condition first after which the first condition is evaluated.

According to an embodiment, the second condition further comprises that the mechanical transmission, or gearbox, is operated in a direct acting gear, or direct gears. In other words, the control unit is further configured to notify the driver to activate the cruise control function of the vehicle only if the mechanical transmission is operated in a gear value which corresponds to direct acting gears, or substantially direct acting gears. Hence, the driver notification system notify the driver to activate cruise control when the transmission, and thereby the drive train of the vehicle, is operated with low transmission losses which improves the efficiency and fuel economy of the operation of the vehicle. For example, the transmission losses and losses in the drive train of the vehicle due to friction, lubrication, wear, and/or tribological interactions in the transmission are further reduced. A direct acting gear, or direct gear, typically is designed such that the power transfer occurs by direct coupling of the input shaft to the output shaft which provide efficient power transfer.

Furthermore, according to an embodiment, the set of cruise control conditions of the driver notification system further comprises a third condition that the first and second conditions are fulfilled simultaneously during a predetermined, or preset, activation time period. This means that the control unit is configured to control the driver indicator to notify the driver to activate the cruise control if the first and second conditions are fulfilled during the preset activation time period. Hence, the driver notification system is provided with a suitable timer function, or delay function, which may be arranged to match, or delay, the notification of the driver until a more suitable situation occur. By determining that the first and second conditions are both present during the preset activation time period, before the driver is notified, the driver notification system is enabled to better ensure that the driver is operating the vehicle in a state suitable for cruise control. An example, when the vehicle speed is above a preset limit, a certain gear is engaged, and the driving has been like this during a certain time period, i.e. the activation time period, the driver should be notified to activate the cruise control. A timer device may be integrated with, or connected to, the control unit for enabling timekeeping and controlling of the duration of each condition, or desired conditions, of the set of cruise control conditions. The activation time period may be set at factory level, set by the driver or a vehicle system operator, for example by remote and/or wireless configuration. According to an example, the activation time period may be set between 0.1 minutes and 30 minutes, preferably between 1 minute and 15 minutes, more preferably between 3 minutes and 8 minutes. Also, the activation time period may also be set to about 5 minutes.

The control unit of the driver notification system may also, according to one embodiment, be configured to control the driver indicator to notify the driver during a predetermined notification time period. Hence, when the control unit receives information and determines that the set of cruise control conditions are fulfilled, the control unit activates the driver indicator, wherein the driver indicator is maintained active, in a notifying state, during the predetermined notification time period. During the notification time period the driver will be able to perceive the notification signal, which e.g. may be a visual or audible notification signal.

Optionally, the control unit is configured to interrupt the notification of the driver after that the notification time period is over, or has elapsed. This may typically be executed even if the set of cruise control conditions are still fulfilled, or true. In other words, if the driver indicator is in the active notifying state, but the cruise control is not activated during the preset notification time period, the driver indicator is interrupted, or deactivated, by the control unit. Also, the control unit may be arranged to reactivate the driver indicator during a new notification time period each time the cruise control conditions are determined to be true, or fulfilled. Moreover, if the driver indicator is active, i.e. in a notifying state, and the cruise control function of the vehicle is activated, the control unit is typically configured to interrupt the notifying of the driver.

According to one embodiment of the driver notification system, it further comprises a telematics device arranged to collect vehicle operating information and vehicle cruise control activity information, wherein the telematics device is arranged to provide the vehicle operating information and vehicle cruise control activity information to a fleet management system. In particular, the telematics device may, over time, collect, or measure, information containing vehicle speed, transmission operation state, and cruise control settings. Vehicle operating information may also comprise further information such as driver behavior, further operating information relating to vehicle speed, vehicle position, etc, and other vehicle information which may be useful in a fleet management system.

The collected vehicle information may be processed, stored in memory device, and provided with a time stamp, which allow for evaluation of vehicle driving operation and performance. In particular, the vehicle information collected by the telematics device allows for management and evaluation of the operating characteristics of a single vehicle or a set of vehicles in a fleet. For example, suitable driving styles in terms of fuel economy and driver behavior may advantageously be quantified, measured, and studied over time or over vehicle operating cycles.

Optionally, according to one embodiment, the telematics device may be configured to provide the vehicle information to a fleet management system, for example, via, at least partly, a wireless fleet management communication system. The telematics device may be adapted to be arranged in the vehicle and connected to, or integrated with, the control unit of the driver notification system. The telematics device may further be arranged to report the vehicle information via sending and receiving

information via the telematics system to a fleet office. In particular, vehicle information which provides calculated performance data of the personal driving style of the driver may be reported. In more detail, such information may for instance be based on how often the driven it utilizing the cruise control in relation to how often, and under how long time, the driver

notification system notifies the driver to activate cruise control. Hence, cruise control utilization rate, fuel economy and efficient operation of the vehicle may be further improved and facilitated.

According to a second aspect thereof, the present invention relates to a method for notifying a driver during operation of a cruise control equipped vehicle having an internal combustion engine and a mechanical transmission. The method comprises determining a first condition, or conditional

expression/requirement, that the vehicle has a speed above, or coinciding with, a predetermined vehicle speed value, VSv, determining a second condition that the mechanical transmission, or the gearbox, of the vehicle is operated in a predetermined gear value, VGv, or set of gears, and notifying the driver of the vehicle to activate cruise control if the first and second conditions are simultaneously fulfilled. Hence, a method for notifying the driver of a vehicle to activate the cruise control function which enables improved fuel economy and improved operation of the vehicle, is provided. In particular, the driver is notified to activate the cruise control when suitable condition for activating the cruise control are simultaneously present in a driving situation. Suitable vehicle operating conditions correspond to a certain vehicle speed and a certain gear value, such as the top three gears/speeds of the transmission, or the highest gear/speed. Further advantages of the method follow from the above description with reference to the first aspect of the invention, i.e. the driver notification system.

According to an embodiment of the method, the step of determining the second condition comprises determining that the mechanical transmission of the vehicle is operated in a direct acting gear. In other words, the preset gear - value defined by the second condition comprises that the transmission is operated in a specific gear, which gear is a direct acting gear.

Advantageously, by only notifying the driver to activate cruise control when the vehicle is operated in a direct acting gear, the operation and driving of the vehicle will be energy efficient since direct acting gears typically allow for less drive line energy losses in the transmission.

The method may, according to a further embodiment, further comprise a step of determining that the first and second conditions are fulfilled simultaneously during a predetermined activation time period. In order words, the method comprises a third condition which is defined by determining if the first and second conditions are fulfilled during a certain time period. This third condition is advantageous in that the method for notifying the driver is provided with improved conditional requirements which ensures that the driver is notified only when the vehicle is driven and operated in a state in which it is suitable to activate cruise control. For example, it is more likely that the driver is driving the vehicle on a main road at a steady cruise speed, wherein the transmission is operated in a specific, or direct acting gear, if the first and second conditions are fulfilled during a certain time period. Hence, the probability of notifying the driver to activate cruise control in a situation in which the driver only for a short period of time operates the vehicle such that the first and second conditions are fulfilled, such as when driving in a urban area, is allowed to be limited.

In addition, the method may further also comprise interrupting the notifying of the driver. Hence, the notification of the driver to activate the cruise control is turned off, or deactivated. Advantageously, the notification of the driver may be interrupted after a predetermined notification time period.

According to one embodiment of the method, it comprises collecting vehicle information and vehicle cruise control activity information. The vehicle information may contain driver specific operating data, such as how well the driver is following the cruise control recommendation provided by the method for notifying the driver. Moreover, the vehicle information may advantageously be provided, or reported, to a fleet management system which allows for determination and evaluation of vehicle driving and operating performances. Hence, driver support functions and feedback may be provide and processed centrally at a fleet office, and efficient driving behavior and overall improved fuel economy of a fleet of vehicles may be facilitated. Furthermore, the invention may also be embodied in a computer program comprising program code means for performing the method, and/or embodiments, of the present invention when said program is run on a computer, or on a micro processor in a control unit. Hence, the invention may be embodied in a computer program product comprising program code means stored on a computer readable medium for performing the method steps of the present invention when said program is run on a computer. For example, the computer readable medium may be a medium capable of storing data in a machine-readable format and/or a medium that is capable of containing, storing, communicate, propagate the computer program for use by or in connection with a system or device.

Other objectives, features, and advantages of the present invention will appear from the following detailed disclosure, from the attached dependent claims as well as from the drawings.

Brief Description of Drawings

Embodiments of the invention will now be described, by way of example, with reference to the accompanying drawings. It is to be noted that the drawings typically are schematic exemplifying representations of embodiments of the invention. Fig. 1 schematically illustrates an embodiment of the driver notification system according to the present invention.

Fig. 2 schematically illustrates a further embodiment of the driver notification system according to the present invention.

Fig. 3 schematically illustrate the driver indicator arranged in the dashboard according to an embodiment of the present invention.

Fig. 4 schematically illustrates a further embodiment of the driver notification system according to the present invention. Fig. 5 schematically illustrate a statistical table of vehicle operating data.

Fig 6 illustrate a flow chart of a method according to an embodiment of the present invention.

Fig 7a-b illustrate a flow chart of a method according to embodiments of the present invention.

Detailed Description of Embodiments of the Invention Fig. 1 schematically illustrates a driver notification system 1 comprising a driver indicator 2 and a control unit 5. The driver indicator 2 is schematically illustrated as a device separated but connected to the control unit 5 via controlling means, such as a cables or wires, capable of transferring a controlling signal from the control unit 5 to the driver indicator 2. However, the control unit 5 may also be integrated with and connected to the driver indicator 2 such that the control unit and driver indicators form a single device, or unit.

The driver notification system 1 is adapted for being arranged in a cruise control equipped vehicle typically having a internal combustion engine and a mechanical transmission. For example, the vehicle may be a heavy truck, bus or passenger car, or any other road vehicle which is equipped with a cruise control. The driver indicator 2 is arrange for notifying the driver, or operator, of the vehicle during operation and is therefore arranged in close proximity to the driver's vehicle operating position. Moreover, the driver indicator is 2 arranged such that a notification signal from the driver indicator 2 is perceivable by the driver. For example, the driver indicator may notify the driver via a visible or audible signal, such as a visual display or light which may be illuminated in order to notify the driver, or a speaker device which produces a notification sound for the driver. Typically the driver indicator 2 is perceptibly arranged on the dashboard of the vehicle.

The control unit 5 is configured to control the driver indicator 2 to notify the driver to activate the cruise control function of the vehicle if a set of cruise control conditions are fulfilled. The cruise control conditions represent conditional expressions, or statement, which define the operation or function of the driver notification system 1. A first condition stipulates that the vehicle should have speed above, or coinciding with, a predetermined vehicle speed value, VSv. A second condition stipulates that the mechanical transmission of the vehicle should be operated in a predetermined gear value VGv. The control unit 5 is configured to receive and process instantaneous vehicle information. Instantaneous vehicle speed data VSinst may be received in the control unit 5 and processed in order to determine if the instantaneous vehicle speed of the vehicle is above, or coinciding, with the predetermined vehicle speed value VSv, (VSinst >= VSv). In addition, the instantaneous vehicle operating gear data, VOGinst, may be received in the control unit 5 and processed in order to determine if the vehicle is operated in the

predetermined gear value. Accordingly, the control unit 5 may be configured to control if the first and second cruise control condition are fulfilled. If the set of cruise control conditions are fulfilled, the control unit 5 is further configured to produce a notification signal, or activation signal, to the driver indicator 2. The set of cruise control conditions may also comprise further conditions in addition to the first and second conditions.

Typically, the control unit 5 comprises a CPU, microprocessor, or electronic control device which enables the control unit 5 to process and evaluate vehicle information containing e.g. vehicle speed data, vehicle operating gear data, vehicle position data, etc. The control unit may further be arranged to be provided with vehicle information from, and to communicated with, vehicle control systems, engine control units, computer-controlled subsystems and sublevel vehicle sensor devices such as vehicle speed sensors, and engine shaft or drive shaft rotation detection means, or detectors. Typically, vehicle information, such as vehicle speed and gear data is provided in the form of a digitally represented signal, or value.

As further illustrated in Fig.1 , instantaneous vehicle operating information, or data, is provided to the control unit 5 via a vehicle speed data input 3 and a vehicle operating gear data input 4. According to further embodiments of the invention, further inputs may be arranged in order to provide suitable vehicle information to the control unit 5. Fig. 2 illustrates a schematic structure, or assembly, comprising the control unit 5 and driver indicator 2, as well as auxiliary devices. In different combinations they form a plurality of embodiments of the driver notification system 1 . As shown, the control unit 5 is be connected to, or integrated with, further vehicle information providing devices, which thereby may be adapted to be used in combination with the control unit 5 and the driver indicator 2 in separate embodiments or in together in various combinations. For example, in one embodiment the control unit 5 is further connected to a timer device 10, and according to another embodiment, the control unit 5 may be connected to a timer device 10 and a telematics device 1 1.

As schematically illustrated, a timer device 10 is connected, or integrated, with the control unit 5. The timer device allows the control unit to measure and determine the duration of true or falls states of the cruise control conditions configured into the control unit. In other words, if the first cruise control condition is fulfilled, the control unit may generate a first on-signal, and a second on-signal if the second cruise control condition is fulfilled. The control unit may further be configured to measure the duration of the first and second on-signals and compare the result with a predetermined activation time period value. This allows the control unit 5 to determine if the first and second condition have been fulfilled simultaneously during the predetermined activation time period. The timer device may also provide a time stamp associated with each one of the first and second on-signals for logging and later evaluation of vehicle driving and operating characteristics.

As further illustrated, the control unit 5 may be connected to a cruise control unit 14 which controls the cruise control function of the vehicle. The control unit 5 and the cruise control unit 14 may be configured to

communicate with each other in order for the control unit to receive

information of the activation setting of the cruise control function of the vehicle, i.e. if the cruise control function is activated or not. This allow the control unit 5 to be configured with a conditional statement that the notification of the driver to activate cruise control may only be executed if the cruise control is set in an non-active mode, i.e. if it is deactivated. Furthermore, the control unit 5 may be connected to and arranged to communicate with a telematics device 1 1 arranged in the vehicle. The telematics device may operate in combination with a transceiver/receiver device 12 and a GPS device 13. Thereby, the vehicle position may be logged and match with vehicle operating information which may be associated with a time stamp, and provide to a fleet management system.

Furthermore, the control unit 5 may be configured to receive vehicle position information from the GPS device and/or remote instructions via the telematics device. Such position information or instruction may define additional cruise control condition for further functionality of the driver notification system. For example, the control unit may be configured not to notify the driver to activate the cruise control, if the vehicle is positioned in predetermined areas, such as urban areas. Also, instructions received by the telematics device may advantageously adjust the conditional values of the set of cruise control conditions, such as the vehicle speed value and the vehicle gear value.

As further illustrated in Fig. 2, a speed sensor 6 and a transmission sensor 7 are arranged to provide input signals to the control unit 5. Optionally, the signals may be pre-processed by the central vehicle control unit(s) 8, wherein the instantaneous vehicle speed data and instantaneous vehicle gear data is provided to the control unit 5 by the central vehicle control unit(s) 8.

Optionally, the control unit 5 may connected to a driver setting device, or selector 15. With the driver settings device 5 the driver may adjust the configuration of the control unit 5 by selecting the predetermined vehicle speed value, predetermined vehicle gear value, activation time period, notification timer period, etc. Also, individual driver specific settings may automatically be implemented for different drivers of a vehicle.

In Fig. 3, a driver indicator 2 in the form of readable display is shown. The display is arranged in the dashboard 20, or instrument panel, of a vehicle. In this position, the driver indicator is easily perceived and noticed by the driver during operation of the vehicle. The display may illuminate when it receives an activation signal from the control unit which may be suitable arranged behind the dashboard. During operation of the vehicle and when the control unit detects that the driving fulfills the set of cruise control conditions, the driver indicator will inform and notify the driver that it is suitable to activate the vehicle's cruise control.

Fig. 4 schematically illustrates an embodiment of the driver notification system 1 arranged in a truck 21 . The control unit 5 is connected to the driver indicator 2 which is arranged close to the driving position of the driver. The control unit 5 is further connected to a telematics device 1 1 and a

transmitter/receiver device 12 in the truck 21. Vehicle operating data collected from, or provided by, the control unit 5 may be bundled in a dataset and reported via the telematics device 1 1 and via a communication network 30, such as a wireless communication system, to a fleet management system 31 which is arranged to manage and control communication of fleet and vehicle information in a network based computing network. The communication network 30 may be of, or a combination of, a wireless, wired, LAN, WAN, internet, intranet, peer-to-peer network, optical, or other communication networks. The fleet management system receives the vehicle operation data which allows for analysis and controlling of vehicle tracking, vehicle

diagnostics, driver and fuel management. In particular, vehicle operating data containing information of driver behavior in terms of utilization of the cruise control function based on the driver notification system 1 may be reported and derived from each vehicle in a fleet. The driver notification system 1 in combination with the telematics device 1 , communication network 30, and fleet management system 31 forms a vehicle operation telematics system for e.g. driver, fuel, and vehicle management.

Fig. 5 schematically illustrate a statistical representation of vehicle operating data in the form of a table, wherein the vehicle operating data may be collected and compiled according to a periodic plan. In the first column of the table, the operating state of the transmission is indicated by different gear values. In the second column, the distance driven for a specific gear and during a specific period is indicated. In the third column, the utilization rate of the cruise control function is indicated in the form of percentage of associated distance for each gear. The utilization rate of the cruise control is typically based on, and put in relation to, information provided by the driver notification system, wherein e.g. the information provides a measurement of the total time, or total distance, during which the vehicle has been operated in conditions suitable for cruise control, i.e. vehicle cruise control activity information. In other words, the utilization rate of the cruise control, as determined by the driver notification system, is measured and represented in the table which allows for driver and vehicle operation evaluation. In particular, how often the driver activates the cruise control based on the notifying signal of the driver notification system may be measured and represented graphically. The vehicle operating data may also be represented in charts and graphs. Furthermore, the utilization rate of the cruise control may also be measured in relation to the total drive distance, or the total drive time, during a specified period.

Fig 6 illustrates a method 50 for notifying a driver during operation of a cruise control equipped vehicle having an internal combustion engine and a mechanical transmission according to an embodiment of the present invention. The method comprises a set of cruise control conditions which form conditional expressions defining the execution of the method.

At block 51 , a first cruise control condition is evaluated by determining that the vehicle has a instantaneous vehicle speed above, or coinciding with, a predetermined vehicle speed value, VSv. The determining of the first cruise control condition may comprise processing received instantaneous vehicle speed data, VSinst, based on signals provided by from e.g. vehicle speed detectors, a GPS device, or drive shaft rotation detectors. For example, the vehicle speed may be derived from the revolutions per minute, rmp, of the main drive shaft of the vehicle and compared with the predetermined vehicle speed value, VSv, as defined by the first cruise control condition. In other words, at block 51 , it is determined if the data value of VSinst is greater than, or equal to VSv. Alternatively, the vehicle speed value VSv may be a suitable vehicle speed interval, or range, wherein the first cruise control condition is fulfilled if the instantaneous vehicle speed data, VSinst, is in the VSv interval.

At block 52, a second cruise control condition is evaluated by determining that the mechanical transmission of the vehicle is operated in a predetermined gear value. The determining of the second cruise control condition may comprise processing received instantaneous vehicle operating gear data, VOGinst, based on signals provided by e.g. transmission gear sensing means, sensors, a gear selector, or a transmission control unit. For example, the operating gear of the transmission may be derived by

processing and comparing the rotational speed of the drive shaft of the vehicle and the rotational speed of the engine shaft, wherein the transmission is arranged between the engine shaft and the drive shaft, and wherein the drive shaft is connected to the drive wheel(s) of the vehicle. The relation between the rotational speed of the drive shaft and the engine shaft defines the gear ratio of the transmission and thereby the operating gear of the transmission. For example, a substantially direct acting gear typically provides a ratio of substantially one (1 ) between the rotational speed of the drive shaft and the engine shaft.

At block 80, the driver of a vehicle is notified to activate cruise control if the first and second cruise control conditions are fulfilled simultaneously, or substantially simultaneously. Furthermore, the step of notifying the driver may further comprise producing a activation signal for activating a driver indicator.

With reference to the method in Fig 6, the order of the determining of the set of cruise control conditions may be alternated, or be executed in a desired order such that it is determined that the cruise control conditions are fulfilled essentially simultaneously in a driver situation.

Fig 7a illustrates a further method 50 for notifying a driver during operation of a cruise control equipped vehicle. This method comprises similar cruise control condition evaluations, as described with reference to the method described in Fig. 6. In addition, the method comprises a third cruise control condition.

At block 53, the third cruise control condition is evaluated by

determining if the first and second condition are fulfilled simultaneously, during a predetermined operating time period. This third cruise control condition should also be fulfilled, or true, before the notification of the driver, at block 80, is performed. Typically the determining comprises measuring the time duration of signals indicating that the first and second cruise control conditions are fulfilled if the vehicle is simultaneously driven in a suitable speed and suitable gear for a certain period of time. If it is fulfilled, an activation signal activating the driver indicator is produced.

Prior to initiating the evaluation of the cruise control conditions, a suitable pre-step may be executed in order to determine if the cruise control is activated or not. Alternatively, the set of cruise control condition may further comprise a condition that the cruise control is not activated, or not in action, in order for the notification of the driver to be executed.

Fig. 7b illustrates a alternative embodiment of the method described in relation to Fig. 7a. As illustrated, the first and second condition may be evaluated in parallel, or in a separated manner. In other words, the first and second cruise control condition is evaluated at the same time. With reference to Fig. 6, the first and second conditions may also be evaluated in parallel.

The invention has mainly been described above with reference to a number of explicitly disclosed embodiments. However, as is readily

appreciated by the skilled person in the art, embodiments other than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended claims.

Claims

1. A driver notification system (1 ) comprising

a driver indicator (2) for notifying a driver during operation of a vehicle, said driver indicator (2) being connected to a control unit (5), characterized in that

the control unit (5) is configured to control the driver indicator (2) to notify the driver to activate a cruise control if a set of cruise control conditions are simultaneously fulfilled,

wherein the set of cruise control conditions comprises

a first condition that the vehicle has a speed above, or coinciding, with a predetermined vehicle speed value, and

a second condition that a mechanical transmission of the vehicle is operated in a predetermined gear value.

2. A driver notification system (1 ) according to claim 1 , wherein the second condition further comprises that the mechanical transmission is operated in a direct acting gear.

3. A driver notification system (1 ) according anyone of the preceding claims, wherein the set of cruise control conditions further comprises a third condition that the first and second conditions are fulfilled simultaneously during a predetermined activation time period.

4. A driver notification system (1 ) according to anyone of the preceding claims, wherein the control unit (5) is configured to control the driver indicator (2) to notify the driver during a predetermined notification time period.

5. A driver notification system according to claim 4, wherein the control unit (5) is configured to interrupt the notification of the driver after the notification time period has elapsed.

6. A driver notification system according to anyone of the preceding claims, further comprising a telematics device (1 1 ) arranged to collect vehicle operating information and vehicle cruise control activity information, wherein the telematics device (1 1 ) is arranged to provide the vehicle operating information and vehicle cruise control activity information to a fleet

management system (31 ).

7. Method for notifying a driver during operation of a cruise control equipped vehicle having an internal combustion engine and a mechanical transmission, the method comprising

determining a first condition that the vehicle has a speed above, or coinciding with, a predetermined vehicle speed value,

determining a second condition that the mechanical transmission of the vehicle is operated in a predetermined gear value, and

notifying the driver of the vehicle to activate cruise control if the first and second conditions are simultaneously fulfilled.

8. Method according to claim 7, in which the determining of the second condition comprises determining that the mechanical transmission of the vehicle is operated in a direct acting gear.

9. Method according to any one of claims 7-8, further comprising determining that the first and second conditions are fulfilled

simultaneously during a predetermined activation time period.

10. Method according to claim 9, in which the step of notifying the driver comprises notifying the driver of the vehicle to activate the cruise control if the first and second conditions are simultaneously fulfilled during the predetermined activation time period.

1 1 . Method according to any one of claims 7-10, further comprising interrupting the notifying of the driver.

12. Method according to claim 1 1 , wherein the step of interrupting the notifying of the driver further comprises interrupting the notifying of the driver after a predetermined notification time period.

13. Method according to any one of claims 8-12, further comprising collecting vehicle operating information and vehicle cruise control activity information, and

providing the vehicle operating information and vehicle cruise control activity information to a fleet management system.

14. A computer program comprising program code means for performing the method according to any one of claims 7-13 when said program is run on a computer.

15. A computer program product comprising program code means stored on a computer readable medium for performing the method according to any one of the claims 7-13 when said program is run on a computer.