BE1023741B1 - A vehicle, a continuously variable transmission system, a control method and a computer program product - Google Patents

Abstract

Continuously variable transmission (CVT) system for a vehicle, comprising a variator with two friction elements. A first friction element is coupled to a second friction element by a torque transmitting part, wherein the clamping force or pressure of at least one friction element on the torque transmitting part is adjustable. The CVT system further comprises a controller adapted to retrieve information representative of an upcoming road condition, the controller further adapted to adjust the clamping force or pressure of the at least one friction element on the torque transmitting part on the basis of the retrieved information. .

Description

A vehicle, a continuously variable transmission system, a control method and a computer program product

FIELD OF THE INVENTION

The invention relates to a system and method for controlling a vehicle transmission by using outdated road condition information.

BACKGROUND OF THE INVENTION

A vehicle transmission provides controlled application of engine power by converting speed and torque from a power source. A continuously variable transmission (CVT) is an automatic transmission that allows change through a continuous range of effective transmission ratios. A drive motor feed can be used to deliver variable outgoing speeds and torque while maintaining the feed at a constant angular speed. A CVT may include a variator for providing a mechanical force transmission, the variator comprising two frictional elements, a first frictional element being connected to a second frictional element through a torque transmitting member, such as a (push) belt. A first conical conical disk and a second conical conical disk can be provided, each connected to a shaft. Each axis can comprise a fixed and an axially movable disc. A flexible part such as, but not limited to, a chain or a belt, where a belt can be a segmented steel V-belt, can be arranged clamped between two pairs of conical discs of the conical discs, the space between the discs and hence the Belt running radius can be adjusted by axial movement of the movable disc. The variator can change its transmission ratio continuously.

The CVT efficiency can, among other things, be influenced by the mechanical system efficiency, control system losses and control strategy. When the vehicle is traveling at a constant moderate speed, the control system can take a large part of the energy consumption and also have a major influence on the efficiency of the variator. If the clamping forces in the variator are reduced, the efficiency of the variator can improve and the energy required by the control system can decrease, resulting in an improvement of the efficiency of the CVT. The clamping forces in the variator are also important for the mechanical efficiency of the system. Consequently, reducing the clamping forces can, at least in part, reduce losses of both the operating system and the mechanical system. CVT efficiency may already be at the level of manual transmission (MT), but there is still room for improvement, as current CVT losses may be greater than compared to MT. The main reason for the lower efficiency of CVTs is the high clamping force needed to transfer the motor torque. In order to prevent slip of the torque-transmitting part, or belt slip, the clamping forces in CVTs are usually always higher than necessary for "normal" operation, i.e. the situation without failures and / or torque peaks. Higher clamping forces can therefore cause higher losses in both the hydraulic and the mechanical system, for example as a result of increased pump losses, additional mechanical stress on the variator parts which result in increased friction losses. The higher clamping forces can also reduce the durability of the belt due to increased wear, since the net tensile force in this element is greater than strictly necessary (with normal use). Partly as a result of the clamping forces, heavier components may be required and therefore be arranged in the CVT system, which may also have an adverse effect on the power density.

Partly because of this, the clamping force of the torque-transmitting part (for example, push belt) has an important influence on the efficiency of a CVT. In fact, the efficiency of a CVT can be largely determined by the clamping force. Therefore, reducing the clamping forces can lead to better efficiency.

Lowering the variator clamping forces can be advantageous for fuel consumption due to the decrease in energy consumption by the hydraulic pump of the CVT and reduction of friction power losses in parts of the variator. The reduced clamping forces can also be favorable for the power density since the push belt tensions decrease. However, reduced clamping forces can also increase the risk of push belt slip, for example in the case of coupling peaks, or slow or delayed hydraulic responses.

In order to deal with unexpected coupling peaks caused by driving on a road with poor and / or different road conditions, a higher clamping force can be used as the minimum required to prevent belt slip. This precautionary measure is required as the road conditions for the vehicle are unknown. However, if no such over-clamping is used in the CVT, disruptions can lead to serious slip cases that could potentially damage the CVT variator. It is known to use the measurements of the actual torque or of the slip in the variator to use a clamping force with a lower safety margin, i.e. reduced clamping force and / or no over-clamping, while reducing the risk of excessive slip .

In addition, in known CVT control systems, sensors for measuring wheel speed or acceleration can also be used by the control system to make a suitable adjustment of the clamping force. US2005 / 159,259 describes a method for detecting irregularities by means of the gradient of the cumulative difference between measured wheel speed and the weighted average value of the wheel speed, in order to adjust the contact pressure on the cone discs of a variator based on the detected state from the road. In such feedback control systems, the detection of road irregularities may be too late, so that during “normal” driving conditions (for example, driving conditions without road irregularities), the clamping force must be sufficiently large to withstand unexpected large shocks and / or coupling peaks due to vehicle driving over road irregularities. Actually, feedback on control wheels which use wheel speeds detect events on the wheels. However, there is no guarantee that the events on the wheels come from the road irregularities. The wheel speed events are linked to the road condition. Although the operating system can be implemented with relatively simple means, the accuracy and assurance provided also tends to be limited.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a system, a method and a vehicle which overcomes at least one of the aforementioned disadvantages, while maintaining the advantages.

It is a further object of the invention to improve the efficiency of a CVT system and / or a vehicle comprising the CVT system.

It is a further object of the invention to provide an efficient control strategy for a CVT, wherein the risk of slipping in the variator of the CVT is reduced when the vehicle is confronted with different road conditions, for example slipping the torque transferring part in the CVT. variator, such as a push belt (see “belt slip”).

The CVT system may comprise a variator with two frictional elements, a first frictional element being coupled to a second frictional element by a torque transferring member. A clamping force or pressure of at least one friction element on the torque-transmitting member is adjustable. The CVT system further comprises a controller which is adapted to retrieve information representative of an upcoming road condition. Furthermore, the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the torque-transmitting part on the basis of the outdated information.

The information representative of the road condition can relate to road conditions such as hill information, weather conditions, snow, rain, slope of the ground or road, objects on the road, potholes, curbs, road irregularities, road surface, road roughness, traffic, etc. it will be clear that the information representative of the road condition may comprise a numerical value for a road condition. It is also possible that the information representative of the road condition is encrypted or coded. It is also possible that the information representative of the road condition includes a classification of the road condition. Unless otherwise stated, road condition information herein refers to information representative of the road condition.

In the variator, power can be transferred from a first cone disc to the second cone disc by means of a torque transferring member. The torque transferring member can be a push belt arranged between the first cone disc and second cone disc, power being transmitted by friction between the push belt and cone disc discs. Therefore, greater efficiency can be achieved by controlling the pressure or clamping force for the torque transferring part or push belt of a CVT, using upcoming road condition information retrieved by the controller.

As already mentioned above, the efficiency of a CVT transmission is largely determined by the clamping force of the torque-transmitting member (e.g., push belt). Optimizing to the lowest clamping force at which no slip occurs leads to low hydraulic pressures. However, to cope with unexpected coupling peaks caused by different road conditions, a higher clamping force is usually applied to obtain a minimum clamping force required to avoid belt slip when faced with different road conditions. The higher clamping force can have an adverse effect on the efficiency, which results in a higher fuel consumption of the vehicle. According to the present invention, the upcoming road conditions for a vehicle are traced by the controller. Thereby (relevant) road conditions which will be experienced by driven wheels of the vehicle and therefore by the CVT can be predicted and processed in order to evaluate the effect on the CVT of the vehicle before this effect is actually experienced. For example, upcoming road conditions for a forward-moving vehicle comprising a CVT system can be used to determine the (relevant) road conditions in advance and, if necessary, increase the clamping force or pressure of at least one friction element on the torque transferring part, taking into account with the outdated road conditions. As a result, the use of a general reserve, safety margin or over-clamping for the clamping force or pressure can be avoided or at least greatly reduced, whereby the efficiency of the CVT system can be improved. Another advantage is that the risk of adverse effects such as belt slip in the CVT can be reduced, which can improve the service life and / or reduce maintenance costs.

Accordingly, instead of using direct measurements for the detection of slip conditions and feedback, for example when the wheels of a moving vehicle reach a pit on the road, the condition of the road surface can be identified in advance by the controller in order to obtain the required clamping force predict and, if necessary, adjust the clamping force thus avoiding belt slip in the CVT in advance or simultaneously with the road condition being experienced.

Optionally, the controller is adapted to predict a change in input and / or output torque of the variator based on the retrieved path condition information, and to adjust the clamping force or pressure of the at least one friction element on the torque-transmitting part according to the predicted torque change. The adjustment of the clamping force or pressure in the variator can be performed prior to or simultaneously with the torque change that occurs.

As a result, an assessment of the road condition relevant to the vehicle can be obtained in advance. For example, information regarding road irregularities and / or road roughness can be detected prior to shock events so as to be able to increase the clamping force in time. This allows the vehicle to be configured to apply a lower clamping force under "normal" driving conditions, which can lead to a reduced fuel consumption of the vehicle. Driving comfort can also be improved. Furthermore, wear can be reduced, which also increases the service life of the vehicle and its components.

A higher clamping force with reserve can thus be avoided if the road conditions of the vehicle's driving route are predicted and / or anticipated by the vehicle. To realize this, the road conditions are obtained in advance. The obsolete data can then be analyzed by the controller thus recognizing the road conditions in advance and taking them into account.

Optionally, the controller is adapted to predict a moment at which the input and / or output torque of the variator will change based on the retrieved path condition information, and to adjust the clamping force or pressure of the at least one friction element transferring to the torque share according to the predicted torque change. The adjustment of the clamping force or pressure in the variator can be performed prior to or simultaneously with the predicted torque.

A vehicle comprising a CVT according to the present invention can use a lower reserve and can also keep the reserve low so that efficiency gains can be avoided. This effect can be particularly drastic when a vehicle drives under normal road conditions with a conventional reserve or safety margin for the clamping force or pressure in the variator, designed to accommodate unexpected coupling peaks. The controller of the CVT system may be arranged to pre-check the clamping force or pressure in the variator prior to impact to ensure that the required clamping level is reached at the time of the impact or even before it. Advantageously, post-control of clamping force or pressure in the variator after impact can also be performed by the controller to ensure that the required clamping force level or pressure level in the variator is maintained long enough, for example, to prevent belt slippage due to the decrease in torque oscillations .

Optionally, the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the torque-transmitting member if the predicted change in input and / or output torque of the variator exceeds a predetermined threshold value.

Optionally, the controller is adapted to retrieve road condition information from a detector for detecting a road condition.

The upcoming road conditions can be determined from data obtained from a detector, such as a substantially non-intrusive remote sensing system for recognizing relevant road condition characteristics. A detector may be a sensor system comprising one or more sensors which are arranged to detect information about an environment in which the vehicle is located or other information that may be of interest to the vehicle, such as future road condition information in a future trajectory of a (moving) vehicle. This means that changing road conditions can be identified in time. Although the detector can be arranged to obtain (relevant) upcoming road condition information for the vehicle, the information can also be obtained from a memory, a network, a data transfer, a cloud, other vehicles, other entities and / or sensor systems arranged for other systems, such as, for example, sensors adapted to provide autonomous functions for self-driving vehicles. Consequently, the controller can dynamically adjust the drive of friction elements of the CVT variator based on the outdated upcoming road condition information. Furthermore, it is possible to use both data from the remote sensing system supplied by a detector and data from the cloud, with a view to better anticipating the road conditions for the vehicle.

Optionally, the detector is adapted to determine the road condition for the vehicle.

Optionally, the detector is placed in the vehicle. For example, the detector can be arranged at the front of the vehicle to provide a frontal detection.

Optionally, the controller is adapted to be wirelessly connected to the detector. The detector can be set up in or on the vehicle while it is wirelessly connected to the controller. However, alternatively or additionally, upcoming road condition information can be retrieved from a detector arranged on a different structure.

A wireless communication system can be arranged to provide the wireless communication between the controller and the detector. The controller can be configured to be wirelessly connected to one or more other vehicles, sensors or other entities, either directly or via a communication network. To that end, the wireless communication system may comprise an antenna and a chipset for communication with the other vehicles, sensors or other entities, either directly or via a wireless interface. The chipset or wireless communication system can generally be arranged to communicate according to one or more other types of wireless communication (e.g. protocols) such as Bluetooth, communication protocols described in IEEE 802.11 (including any IEEE 802.11 revision), cellular technology (such as GSM, CDMA, UMTS, EV-DO, WiMAX or LTE), Zigbee, dedicated short distance communication (DSRC), and radio frequency identification (RFID) communication, among other options. The wireless communication system can also take other forms.

Optionally, the controller is adapted to communicate with the detector, the detector being placed in a further vehicle, which preferably runs in front of the vehicle with the continuously variable transmission system.

Optionally, the controller is adapted to communicate with the detector, the detector being placed stationary with respect to the road.

Optionally, the controller is arranged for communication with a network for retrieving road condition information.

The data from the sensors on the vehicle that contribute to obtaining an estimate of the local road condition can be communicated with the cloud, or other network system, to build a database of road road conditions. This data can then be used by other vehicles that have access to the cloud. Direct communication between different vehicles may also be possible to obtain an improved and / or faster picture of the road conditions relevant to the vehicle. Previous data can also be stored locally and / or in the cloud, in order to improve the efficiency of determining the road condition.

In an advantageous embodiment, the road condition information can be stored in a cloud and / or a server to summarize and offer or share suitable information about a local and global road condition to the outside world, whether it is a next vehicle or not, a local server connected to a central database or an internet service. Advantageously, the information retrieved from the cloud can be used by the controller in combination with a detector to increase the clamping levels of the CVT variator, if necessary or desirable. The communication can take place by means of any telecommunication device, for example standard protocol, whereby the information can be sent and received to / from local servers and other vehicles and also local measuring devices on (the side of) the road. A local server can collect information about the local roads. This local server can be connected to a global server, where road data from a large area is collected, whereby certain data analysis algorithms can be used to more accurately determine the road condition data, as well as the impact on the vehicles in use, with regard to clamping force. The nature of the information that can be exchanged between the vehicle and the cloud can be: GPS location, weather conditions, road type, IRI classification, objects (for example pits, curbs, etc.), object properties (height, width, location), camera photos , wheel speed information, tire pressure information, accelerometer information, internal CVT speed sensor information, clamping force information, and so on. Many other options are possible. In some examples, the data can be summarized for communication.

Optionally, the network comprises a memory which stores the road condition information.

Optionally, the network communicates with one or more detectors adapted to determine the road condition, the one or more detectors being stationary with respect to the road and / or in vehicles.

Optionally, the system comprises a network server configured to provide road condition information to the controller. The network server can be arranged to receive from the controller an indication of a location of the controller, and to transfer road condition information about the location of the controller to the controller.

Optionally, the detector comprises an optical system, such as a digital camera, a radar system, a lidar system, and / or an acoustic system.

The detector can be a substantially non-intrusive remote-sensing system which is arranged at least partially on a front part of the vehicle, in order to determine at least one scanning area for the vehicle, or at least for the driven wheel (or wheels) of the vehicle, i.e. the direction of travel of the vehicle. It is clear that scan areas other than a frontal scan area can also be arranged, for example lateral, bottom, rear and / or 360 ° scan areas. The detector can be a remote sensing system comprising a camera. The obsolete data from the camera, radar, lidar and / or acoustic sensor supply can be used to determine the road conditions in advance in order to increase the system pressure in the CVT if necessary under the detected road conditions. Under normal road conditions, the vehicle can run at a system pressure of the CVT which is kept relatively low, so that unnecessary pressure reserve is not required, thereby reducing or avoiding the loss of efficiency associated with the use of a pressure reserve.

Optionally, the controller is adapted to analyze an image provided by the camera for features indicative of the road condition.

Characteristics indicative of the road condition may include: hill information, weather conditions, snow, rain, slope of the ground or road, objects on the road, potholes, curbs, road irregularities, road surface, road roughness, etc. The characteristic may are relevant for controlling the clamping force or pressure in the variator of the CVT system.

The camera can be any camera (e.g., a photo camera, a video camera, etc.) arranged to take images of the environment or the area around the vehicle in which it is located. To that end, the camera can be arranged to detect visible light, or arranged to detect light from other parts of the spectrum, such as infrared or ultraviolet light. Other types of cameras are also possible. The camera may comprise a two-dimensional sensor, or may have a three-dimensional spatial range. For example, the camera may be a distance detector configured to generate a two-dimensional image that indicates a distance from the camera to a number of points in the environment. Other distance detection techniques and devices can be used in combination with the camera. In an exemplary embodiment, the camera can be configured to use a structured light technique wherein the vehicle illuminates an object in the environment with a predetermined light pattern, such as a grid or checkerboard pattern, and uses the camera to reflect the predetermined light pattern from the object to detect. Based on disturbances in the reflected light pattern, the vehicle can be configured to determine the distance to the points on the object. The camera can be arranged behind a windscreen of a vehicle. However, in other embodiments, the camera can be mounted elsewhere on the vehicle, inside or outside the vehicle.

The process of classifying the road condition information may further include the controller determining a probability distribution (e.g., a Gaussian distribution) of any conditions associated with the detected road condition information. Such probability distribution can take the forms of a discrete probability distribution, continuous probability distribution, and / or mixed continuous-discrete probability distributions. Other types of probability distributions are also possible.

Optionally, the system further comprises a wheel speed sensor and the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the part further on the basis of the detected wheel speed.

Other measurement or detection systems such as wheel speed sensors, accelerometers, CVT internal speed sensor, hand pressure sensors can be used in combination with the detector according to the present invention, to obtain an even more accurate analysis of the local road condition.

Optionally, the system further comprises a hand pressure sensor and the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the part further on the basis of the detected tire pressure.

Optionally, the system further comprises an artificial horizon sensor and the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the part further on the basis of the detected horizon.

Optionally, the system further comprises a steering angle sensor and the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the part further on the basis of the detected steering angle.

The invention further relates to a vehicle comprising a CVT according to the present invention.

Optionally, the vehicle may further comprise the detector of the present invention.

The invention further relates to a network server adapted to transfer information representative of a road condition to a vehicle with a continuously variable transmission according to the invention.

Optionally, the network server is adapted to receive information representative of a road condition from one or more sensors. These sensors can be mounted in a vehicle comprising a CVT according to the invention. The sensors can also be placed elsewhere. Optionally, the network server is adapted to receive information representative of a clamping force or pressure from a vehicle comprising a CVT according to the invention.

Optionally, the network server is adapted to receive from a vehicle an indication of a location of that vehicle, and to transfer information to the vehicle representative of the road condition at and / or close to a location of the vehicle.

Optionally, the network server has an associated memory which stores information representative of road conditions. The memory can be a database. The contents of the memory can be dynamic, whereby it can be regularly or continuously updated with information representative of road conditions obtained from sensors, such as sensors mounted on vehicles comprising a CVT according to the invention, or from sensors positioned elsewhere.

The invention further relates to a method for operating a CVT system for a vehicle, comprising a variator with a first friction element and a second friction element coupled by means of a torque-transmitting part. The method comprises adjusting an optimum clamping force or pressure of at least one friction element on the torque transferring member; retrieving upcoming road condition information; and adjusting the clamping force or pressure of the at least one frictional element on the torque-transmitting member based on the obsolete road condition information.

It is known that the electronic control unit of a vehicle can learn driving behavior over a certain number of driving cycles, with certain driving parameters (e.g. fuel-air mixture) and operating aspects of the vehicle being adjusted accordingly. For example, an adaptive transmission control can adapt the shift characteristics to the wishes of the driver and the driving conditions. Such adaptive systems can be used in combination with the present invention to adapt not only to driving behavior but also to the road conditions at the front, thereby providing a more comfortable experience for the occupants of the vehicle, in addition to increased energy. efficiency.

The vehicle may include sensors such as a Global Positioning System (GPS) device, an inertial measurement unit, a radio detection and ranging (e.g., radar) device, a laser grade cylinder and / or light detection and ranging (e.g., lidar) device, a camera, and / or actuators configured to change a position and / or orientation of the sensors. The sensor system can also include additional sensors, including, for example, sensors which detect internal systems of the vehicle, for example gas monitor, a fuel meter, an engine oil temperature, etc. Other sensors are also possible. The CVT system according to the present invention can use one or more of the sensors of the vehicle's sensor system thus allowing the controller of the CVT system to retrieve upcoming road condition information. The sensor data can also be exchanged, for example wirelessly with other entities.

The controller of the CVT system can be arranged to retrieve road condition information from different sources, such as via a detector (e.g. sensors, camera, radar, laser, lidar, etc.) arranged on the vehicle itself, by a cloud (e.g. wireless communication with a network), by other vehicles in wireless communication with the vehicle, and / or via sensor systems used by the driving control system in an auto-assist, autonomous vehicle or self-driving vehicle. Therefore, sensors used for self-driving vehicles can partially or completely take the place of the detector according to the present invention. The controller of the CVT system can obtain information prior to a shock event in order to be able to increase the clamping force and pressure in a timely manner and to resist unexpected high shocks in the variator.

Sensors for obtaining road condition information can be expensive, especially if accurate sensors for obtaining high quality measurements are set up. However, scanning units can be used to map a road or an area. The obsolete road condition information can be stored in a database. The scanning unit can be a dedicated mapping system. The data can be retrieved by the vehicle comprising the CVT system according to the present invention. The controller may be arranged to use the retrieved data as an important source for retrieving road condition information, or adapted to use the data to improve the prediction of the upcoming road information.

It is also possible that road condition data / measurements from several vehicles are combined to improve the road condition information in a database, so that the data can be continuously improved and kept up-to-date. The road condition information can then be provided as a service to individual vehicles and be traced by the vehicle controller. In addition, road classification systems can be used by the controller. For example, roads can be classified into different classes. By using such a road classification system, the size of the data transfer to the controller can be considerably reduced. In one embodiment, the detector is only used if certain conditions are met. For example, it is possible that certain roads are known from previous analyzes or from a network, so that scanning of the road by a detector can be switched off. The controller of the CVT system can determine when the detector is used to scan the road condition. For this purpose, a certainty and / or quality parameter can be assigned to the outdated road condition information by the controller of the CVT system.

The controller of the CVT system can be arranged to obtain data from one or more sources, the sources being service-based which include a subscription system, while other sources can provide open access. In one embodiment, the controller will first check what the available sources are for providing the upcoming road information, after which the controller can select a multiple number of sources, if available, and make an assessment of the road condition by taking the selected sources into account . In another embodiment, a plurality of vehicles can be arranged to be in communication with each other to exchange information regarding, among other things, the road condition. Sensor data from an autonomous vehicle and / or self-driving vehicle which does not include the CVT control system according to the present invention can be used at least in part by the vehicle comprising the CVT control system.

Furthermore, the CVT system according to the present invention may comprise a computer-readable medium that has been stored in time, which program instructions are stored thereon which are executable by at least one processor for providing the functionality described by the method herein.

In the present description, the variator in the embodiments shown comprises two friction elements and a torque transferring member, however, other combinations of friction elements and torque transferring members are possible.

It will be clear that any aspects, features and possibilities described in the light of the CVT system also apply to the vehicle and the methods described. It will also be clear that one or more of the above aspects, characteristics and possibilities can be combined. BRIEF DESCRIPTION OF THE DRAWING The invention will be further elucidated on the basis of exemplary embodiments which are represented in a drawing. The exemplary embodiments are given by way of non-limiting explanation. It is noted that the figures are only schematic representations of embodiments of the invention which are given by way of non-limiting example.

In the drawing:

FIG. 1 a schematic representation of an embodiment of a CVT system;

FIG. 2 a schematic representation of a control strategy for a CVT system;

FIG. 3 is a schematic top view of a vehicle and surroundings thereof;

FIG. 4a is a schematic side view of a vehicle and surroundings thereof;

FIG. 4b is a schematic top view of a vehicle and surroundings thereof;

FIG. 5a is a schematic top view of a vehicle and surroundings thereof;

FIG. 5b shows a schematic top view of a vehicle and surroundings thereof;

FIG. 6 is a schematic side view of vehicles;

FIG. 7 a schematic representation of a control strategy for a CVT system; and

FIG. 8 is a flow chart of an embodiment of a method.

DETAILED DESCRIPTION

FIG. 1 is a schematic representation of an example of a continuously variable transmission, CVT, system 1 according to an exemplary embodiment of the present invention. The CVT system 1 provides a controlled application of engine power from an engine 11, such as a power tool. In this example, the motor 11 is coupled to an input shaft 18a of the CVT via a clutch 11a. The CVT converts the speed and torque of the motor 11 presented on the input shaft 18a of the CVT to a (different) speed and / or torque on an output shaft 18b of the CVT. The CVT comprises a variator 2 for providing a mechanical power transmission, wherein the supply of a drive motor 18a is used to supply variable speeds and torque to the wheel (s) 13 of a vehicle. The input shaft input can be maintained at a constant speed. The variator 2 comprises a primary cylinder 3 and a secondary cylinder 4. Furthermore, the variator 2 comprises two friction elements 15, 16, namely a first friction element 15 and a second friction element 16, the first friction element 15 being connected to the second friction element 16 by a torque transmitting part 17, such as a push belt 17. Other torque transmitting parts 17 are possible, for example a V-belt, a chain or a flexible part. In this example, the first friction element 15 is designed as a first conical conical disk. In this example, the second friction element 16 is designed as a second conical conical disk. The first conical cone disk 15 is connected to the input shaft 18a. The second conical cone disk 16 is connected to the output shaft 18b. The first conical conical disk 15 comprises two disks 19a, 19b, in this example a fixed disk 19a mounted axially with respect to the input shaft 18a, and a movable disk 19b movable axially with respect to the input shaft 18a. The second conical conical disk 16 comprises two disks 19c, 19d, in this example a fixed disk 19c mounted axially with respect to the output shaft 18b, and a movable disk 19d axially movable with respect to the output shaft 18b. The torque transmitting part 17, shown in this embodiment as a push belt 17, which can be a segmented steel V-belt, a chain, a flexible part, etc. is, for example, clamped between the two pairs of conical discs 19a, 19b and 19c , 19d of the cone discs 15, 16. The space between the discs and thereby the push belt 17 running radius can be adjusted by axial movement of the movable disc 19b, 19d of the first cone disc 15 and / or the second cone disc 16 of the variator 2. In this example, the variator 2 can continuously change its transmission ratio. The CVT system 1 is driven by hydraulic power from a hydraulic drive system 6. The hydraulic drive system 6 has a first hydraulic pressure line 7 which is connected to the first friction element 15 and a second hydraulic pressure line 8 which is connected to the second friction element 16. The clamping force or the pressure of the first friction element 15 and / or the second friction element on the torque transmitting part 17 can be adjusted and controlled using an electronic engine control unit 14 (ECU) or a separate transmission controller 5 (TCU, also known as transmission control module TCM). In this embodiment, the TCU 5 is connected to the hydraulic drive system 6. A digital image processing control unit (DIPCU) can be provided which acts as a central control unit, which processes all kinds of data from sensors, including the outdated upcoming road conditions information. The output of the DIPCU can be used by the TCU 5. However, the DIPCU can also be part of the TCU 5. The DIPCU can be arranged to enable data processing. The TCU 5 can be arranged to control actuators, such as the movable discs of the CVT system 1. The hydraulic system 6 can comprise hydraulic components adapted to convert actuator signals from the TCU 5 into hydraulic pressures. The pressures may include a first and second printing. The first pressure and the second pressure are converted to clamping forces on the first cone disk 15 and the second cone disk 16 by the first hydraulic line 7 and the second hydraulic line 8, respectively.

The TCU or controller 5 can receive input from the cloud (such as road condition, weather conditions, objects, GPS location, traffic information, etc.), from sensors and / or from the DIPCU. Based on a predicted road condition, the controller 5 can set the correct clamping force or pressure of the friction element 15 and / or the friction element 16. The controller 5 can reconstruct the road environment and send a more accurate update to the cloud.

The upcoming road information can be received by the controller 5 through a wired connection or a wireless connection. In wireless data communication, a wireless connection device may be arranged to transmit signals via mobile data transmission protocols such as 3G, 4G, 5G, etc. However, other wireless protocols such as WiFi (e.g. a wireless communication according to the IEEE 802.11 standard or other transmission protocol) may also be used. used to obtain wireless communication. A combination of wireless protocols is possible.

The CVT system 1 according to the present invention can also be used in autonomous vehicles and / or self-driving vehicles. Different computer systems and sensor systems are used in autonomous vehicles for transport from one location to another. A driving control system of the autonomous vehicle can be arranged to receive a multiple number of data points corresponding to an environment of the autonomous vehicle by one or more cameras and / or sensors. For example, lidar sensors can be used to obtain a three-dimensional (3D) point cloud. A lidar system can use a bundle to detect and measure the distance between the vehicle and an object from the reflection of the bundle.

Lidar works independently of the ambient light, so that a 3D map of the environment can be retrieved, even in poor light conditions (for example at night). Although accurate, a lidar system is typically more expensive than, for example, a system comprising one or more cameras and / or radar.

The driving control system may also be arranged to collect information indicative of the road condition in the vicinity of the vehicle. For example, the 3D point cloud of the scanned area by the lidar sensors of the vehicle environment can be used by the controller of the CVT system 1 to retrieve upcoming road condition information for the vehicle. The outdated upcoming road condition information can be used by the controller 5 for adjusting the clamping force or pressure of the at least one friction element 15, 16 on the torque transferring part 17.

The controller 5 of the CVT system 1 can be arranged to retrieve information regarding oncoming road condition with the aid of data from sensors that are already available and provided for the driving control system of autonomous vehicles and / or self-driving vehicles. As a result, the CVT system 1 cannot require the installation of additional sensors and / or detectors, whereby the costs can be considerably reduced.

Controlling the clamping force can be a supplement to the normal calculation and / or control of the clamping forces and pressures in the variator 2. If the required clamping force or pressure is sufficiently high by normal control, the controller can determine the clamping force or pressure cannot be changed in the variator 2.

If it is too low, the controller 5 can determine to change the desired clamping force or pressure.

Other components coupled to or included in the CVT system 1 may include an oil pump 12, further sensors (for example, one or more speed sensors 9, lifting position sensors 9a, ABS speed sensors 9b, turbine wheel sensor 9c, pressure sensors 10, etc.), a drive-neutral reverse , DNR, set 9d, etc. The components of the CVT system 1 can be arranged to work with each other and / or with other components coupled with respective systems in a coupled manner. In other examples, the CVT system 1 may comprise more, fewer, or other systems, and each system may include more, fewer, or other components. In addition, the displayed systems and components can be combined or divided into a number of ways.

FIG. 2 shows a schematic representation of a control strategy for a CVT system 1. Certain environmental conditions 20 for a vehicle comprising a CVT system 1 may be relevant for the operation and control of the CVT system 1. For example, a surface of a road or ground on which a vehicle driving, may be relevant to the control of the CVT system 1. Therefore, the control strategy for the CVT system 1 will acquire information 21 representative of the road condition. The information representative of the road condition can relate to road conditions such as hill information, weather conditions, snow, rain, slope of the ground or on the road, objects on the road, curbs, road irregularities, road surface, road roughness, traffic (e.g. Traffic Message Channel (TMC) data, and the like), etc. It will be appreciated that the information representative of the road condition may include a numerical value for a road condition. It is also possible that the information representative of the road condition is encrypted or coded. It is also possible that the information representative of the road condition includes a classification of the road condition. Unless otherwise stated herein, road condition information refers to information representative of the road condition.

This information is then sent to the controller or TCU 5 of the CVT system 1. According to the example of FIG. 2, the controller comprises two units, namely a clamping force calculating unit which is arranged for determining and / or calculating the clamping force and a pressure setting unit which is arranged for setting the pressure commands. The controller 5 is adapted to predict coupling peaks in the CVT based on received information representative of the road condition, and to adjust the pressure settings sent to the hydraulic system 6. The hydraulic system 6 is adapted to control friction elements 15, 16 on the basis of the pressure setting signals from the controller 5. As a result, the hydraulic system 6 will transfer the hydraulic pressure or the clamping force of the at least one friction element 15, 16 to the torque adjust part 17 as a function of the predicted torque. In this example, controlling the first friction element 15 can be focused on the clamping torque of the primary component of the variator, while controlling the second friction element 16 can be focused on the clamping torque of the secondary component of the variator. The controller 5 can be arranged to separately determine a desired value for hydraulic pressure or clamping force for the first friction element 15 and the second friction element 16.

The time-to-impact of a road condition for all wheels can be calculated based on the vehicle speed and the location of the recognized objects. This can be done for the front wheels, but also for the rear wheels of the vehicle. Even when the wheels are not directly connected to the CVT transmission axles, the bump can cause a vehicle imbalance, which can also be noticed on the other wheels and on the CVT transmission axles. A track determination can be performed for all wheels, which can be based on the vehicle speed and the steering wheel angle signal. When an object or road irregularity is on the track of a wheel, the time-to-impact can be calculated. Left and right wheels can have their own predicted jobs.

The detected objects can be generalized to work on both wheels. However, the impact for each of the wheels can also be considered and calculated separately.

The severity of the impact can be calculated based on the properties of the characteristics (for example objects) of the road. For example an ascending curb can be worse than a descending curb, a larger or deeper pit can have more impact, etc. The same object that affects the non-driven wheels (for example rear wheels) can have less influence than when it affects the driven wheels (for example front wheels) ). Difference in left and right wheels can lead to a different kind of impact. The vehicle speed can play an important role for the impact prediction by the controller 5. The same bump in the road can have a greater severity of impact at higher vehicle speeds.

FIG. 3 shows a schematic top view of a vehicle 24 and the surrounding area 25 thereof. In this example the vehicle 24 comprises a CVT system 1. In the surrounding area 25 various irregularities and objects 26, 27, 28 in the road condition have been detected and identified by the CVT system 1. The vehicle 24 comprises four wheels, namely two front wheels 29 30 and two rear wheels 31, 32. In this example, the vehicle turns to the left, so that the front wheels 29, 30 are turned. The controller 5 can predict the tracks 33, 34, 35 and 36 of the individual wheels 29, 30, 31 and 32, respectively. Irregularities and objects 26, 27, 28, for example their location, location relative to the wheels, size, shape, etc., are part of the road condition information. The controller 5 can then predict an impact based on this obsolete road condition information - here an impact of the presence of irregularities and objects 26, 27, 28 - on the torque in the CVT, for example the torque on the input shaft 18a and / or output shaft 18b of the CVT. Based on the predicted impact, the controller 5 then adjusts the clamping force or pressure of the at least one friction element on the torque transferring part in the variator 2 of the CVT 1 system, if necessary. In this example, the tracks 33, 34 and 36 of the wheels 29, 30 and 32, respectively, are predicted by the controller 5, the tracks not affecting irregularities 26, 27 or objects 28 on the road in the surrounding area 25 of the vehicle 24 . However, track 35 of the wheel 31 is predicted to hit an object 28. The controller 5 can predict torque (peaks) based on the predicted interaction and control the pressure or clamping force in at least one of the friction elements 15, 16 of the variator 2.

A local vehicle environment can be determined in the form of a surrounding area 25. In one embodiment, the observation range can be approximately 7.5 meters in front of the vehicle, and approximately 2 meters behind the vehicle. Other ranges can be used and / or the ranges can be adjustable through the use of actuators which can be controlled manually and / or automatically via the controller 5.

In one example, the controller 5 can be arranged to build up a two-dimensional map of the road in front of, below and behind the vehicle 24. When a new frame, for example image of the camera, is available for analysis, the frame can be added to the front of the existing card, and a frame at the end of the existing card corresponding to a rear of the vehicle can be removed. However, the frames can also be stored in a memory and / or database. This process can provide a complete map of the environment of the vehicle 24 relative to the location of all wheels 29, 30, 31, 32 of the vehicle 24. In this map, the detected characteristics or relevant characteristics of the road condition can be indicated, but not limited to paving, asphalt, rain, snow, etc., or any kind of objects.

FIG. 4a shows a schematic side view of a vehicle 24 and the surrounding area thereof, the vehicle comprising a CVT system 1. The vehicle 24 according to this example comprises a detector 38, wherein the controller 5 of the CVT system 1 is adapted to retrieve the road condition information from the detector 38. In this example, the detector 38 is adapted to determine the road condition for the vehicle 24. The detector 38 is also located at the front of the vehicle 24, thereby establishing a front scanning area 39 on the ground or road 37. The road condition information in the front scanning area 39 is recorded and analyzed by the detector 38. In this example, the controller 5 may be arranged to be wirelessly connected to the detector 38.

The controller 5 receives upcoming road condition information from the detector 38 and adjusts the clamping force or pressure of the at least one friction element 15, 16 on the torque transferring part 17 on the basis of the received road condition information. The controller 5 is adapted to predict a change in input and / or output torque of the variator 2 based on the retrieved path condition information, and for adjusting the clamping force or pressure of the at least one friction element 15, 16 on the torque transferring part 17 according to the predicted torque change .

The controller 5 may be adapted to predict the moment at which the required input and / or output torque of the variator 2 will change based on the outdated path condition information by the detector 38. For this purpose, the distance between the front scanning area 39, the point of contact of each wheel 29, 30, 31, 32 with the ground 37 are important. The speed of the vehicle 24 in the direction of travel 40, and the predicted and / or estimated wheel tracks 33, 34, 35, 36 for each wheel of the vehicle 24 can be important. The adjustment of the clamping force or pressure of the at least one friction element 15, 16 to the torque transferring part 17 according to the predicted torque change can be performed prior to or simultaneously with the predicted moment by the controller 5 of the CVT system 1.

In this example, the detector 38 comprises an optical camera 38 adapted for taking images. The camera 38 may be arranged to perform image processing. For this purpose, the camera 38 may include hardware, such as an application-specific integrated circuit ASIC, so as to perform image processing on the recorded images. A digital processing control unit (DIPCU) can be arranged to allow processing of data. The DIPCU can be a central control unit adapted to process all kinds of image devices, such as image processing dedicated to an embodiment of the present invention. The output from the image processing can be used by the TCU 22. Note that the DIPCU can be part of the TCU. The TCU supply unit 22 can be arranged to receive supply signals of measurements of the road conditions from the camera 38. Furthermore, the TCU output device 23 may be arranged to generate and / or output output signals on the basis of the supply measurements, the control signal or output signal taking into account a prediction of coupling peaks. The pressure of two frictional elements 15, 16 of a variator 2, for example clamping disk clamping force, can then be controlled by the hydraulic system 6, based on the predicted coupling peaks.

The camera 38, arranged to capture an image of a portion of the road 37 in front of the vehicle 24 in the trajectory of the direction of travel 40 of the vehicle 24 and on a front side of vehicle 24, may comprise a lens system which is adapted to capturing one or more images by the camera 38. Furthermore, this image is converted into electronic signals by a digital image sensor. In some embodiments, the image processing step may include basic techniques, such as, for example, white balance correction, focus, and / or contrast enhancement. Alternatively or additionally, digital image processing can be performed by software. A digital processing control unit (DIPCU) can be arranged for transferring raw captured images from the camera 38 to a captured document with all kinds of path properties classified therein, and for making the results available to the TCU 5.

The algorithms involved in image processing can provide a certain calculation time needed for calculating road condition information based on one or more frames. To reduce the calculation time, the size or resolution of the frames can be selected based on the current vehicle speed. In an advantageous embodiment, higher vehicle speeds can lead to larger frames or lower resolution frames. Part of the road can be reconstructed based on one image. The process can be repeated over time to build a road-frame-by-frame environment. It is also possible that road condition information is determined from a plurality of frames. Then inter-frame differences can be used to determine road condition information. In addition, object recognition algorithms can be applied. In some embodiments, the detector 38 may be a stereo optical camera with near infrared image.

In another example, the object recognition algorithm can apply object recognition to identify curbs, pits, and other types of objects. In the case of a curb or pit, the height, width and / or location can be identified. Furthermore, it may also be important for a curb to determine whether the curb is ascending or descending. Furthermore, relevant characteristics when identifying the road condition can be an International Roughness Index (IRI) classification and / or road surface classification.

Different distances L1-L4 are shown in FIG. 4a, where L1 is the horizontal distance between the location of the detector 38 and the point of contact of the front wheels 29, 30 with the ground or road 37. L2 is the horizontal distance between the point of contact of the front wheels 29, 30 with the ground 37 and a front of the vehicle 24. L3 is the horizontal distance between the front of the vehicle 24 and a first field of view edge 42. L4 is the distance between the first field of view edge 42 and a second field of view of the edge 43. In one example, L1 about 1 meter; L2 approximately 1 meter; L3 approximately 4 meters; and L4 are approximately 4 meters. Other configurations are possible.

The sensors of the detector of the CVT system 1 can be manually and / or automatically adjustable by the controller 5 or another control system such as driving control system in row supported, autonomous vehicles and / or self-driving vehicles. For example, when the detector comprises a camera, the detector may also include additional actuators to adjust the field of view of the camera. The adjustment can be made automatically based on the vehicle speed and / or environmental conditions in the vicinity of the vehicle, for example fog, rain, snow, etc. The controller 5 can be arranged to detect whether the field of view of the detector 38 (or camera in this embodiment) is blocked, for example as a result of a vehicle in the vicinity which blocks at least a part of the field of view. In the event that the detector 38 cannot obtain road condition information, the controller 5 can return the CVT to a safe operating mode, applying a safety margin of the clamping force or pressure in the variator, thus reducing the risk of encountering undetected reduce road conditions and prevent belt slippage. If the controller 5 detects other vehicles in the vicinity of the vehicle 24 which can provide the controller 5 road condition information relevant to the path of the vehicle 24 on the road 37, then the vehicle 24 can take this information into account.

The controller 5 can be configured to determine an expected adjustment of pressure or clamping force based on one or more of a location of changing road conditions, a direction of travel of the vehicle 24, the relative movement between obsolete road conditions and the vehicle 24, and the ( expected moment at which the individual wheels of the vehicle 24 hit the obsolete road conditions. The predicted pressure or clamping force can be determined on the basis of an analysis, a simulation and / or comparison of the obsolete road condition data with one or more predetermined sets of road condition data. The one or more predetermined sets of road condition data may include training sets of data points made up of other vehicles which detect road condition data in different scenarios.

For example, each particular set of road condition data can be classified and tagged by the controller 5 on the basis of different characteristics and characteristics, such as identifying characteristics of a road roughness (e.g. changing road conditions, road irregularities, potholes, obstacles, etc.) while driving on the road) and the driving activity of the vehicle 24. The obsolete road conditions and the prediction of the wheels of the vehicle 24 affecting the road conditions can be performed using a clustering analysis, where a dataset from the obsolete road condition data is grouped in such a way that characteristics or objects in the same group or cluster are more similar in a certain sense or different to each other than those in other groups or clusters. Other types of analysis can also be used including one or more supervised and unsupervised learning algorithms. The analysis of the obsolete road condition information can be used to calculate and / or determine a probability distribution of what road condition the vehicle 24 will encounter. Deviations and / or changes to road conditions that may be relevant to the CVT system 1 can be identified from this analysis. The controller 5 can also calculate the estimated or anticipated time for possible contact of each wheel with the upcoming road conditions for the vehicle 24. If necessary, the expected necessary adjustment of the clamping force in the CVT system 1 can be performed in advance or precisely on time. In this way, the controller 5 can prevent adverse effects due to too low clamping forces or pressures in the variator, or prevent a lower efficiency of the CVT system 1 due to too large clamping forces in the variator of the CVT.

In some embodiments, a preferred direction of travel of the vehicle 24 can also be determined based on the analysis of the obsolete road condition information by the controller 5. For example, a route for the vehicle can be proposed to the driver of the vehicle 24, or a route can be followed, for example, with self-driving vehicles. Driving on a lane in which the efficiency of the CVT can be increased may be preferred. For example, on the basis of the obsolete road conditions, a lane can be accompanied by an expected decrease in the necessary clamping force and thus a greater efficiency of the CVT system 1 of the vehicle 24 driving on the said lane.

In some embodiments, the controller 5 can determine features from the outdated upcoming road condition data and provide each feature with a relevance score coupled with the effect on the required clamping force in the CVT system 1 for avoiding slip in the torque transferring part 17 while providing an advantageous efficiency is provided. Such a relevance score can also be coupled with the possibility that a wheel of the vehicle 24 strikes a road feature and / or the severity of the strike.

The effect of a specific road condition (e.g. pit) on the variator 2 a CVT system 1 can also depend on the speed of the driven vehicle 24. Therefore, the controller 5 can not only determine the effect as a function of the vehicle's driving speed, but may also suggest changing the vehicle speed in order to reduce the impact of the obsolete road condition on the CVT system 1. The controller may be configured to provide instructions and / or to suggest adjusting a speed of the vehicle 24 and / or a direction of travel of the vehicle 24 based on the expected necessary adjustment of the clamping force or pressure in the CVT system 1. The data can also be wirelessly supplied to a cloud so that the data can be shared with other users or vehicles. It is also possible to provide the road condition information directly to other vehicles 24 driving in the vicinity of the vehicle 24 via wireless communication. Therefore, the controller 5 cannot be limited to the adjustment of the clamping force or pressure of at least one frictional element 15, 16 to the torque transferring part 17 of a variator 2 of a CVT system 1 based on the obsolete road condition information. In some embodiments, the controller 5 may suggest or instruct adjustment of other parameters, however, the adjustment may also be performed by another control system in communication with the CVT controller 5.

FIG. 4b shows a schematic top view of a vehicle 24 and the surrounding area thereof. The vehicle with a CVT system 1 comprises the detector which determines a field of view 41 for the vehicle. The optical camera 38 of the detector can be placed at a sufficient height to provide a far enough view with the right depth view. The front scanning area 39 is determined by the distance L4 and the field of view angles α and ß. Actuators can be provided to adjust angles a, ß. In this example, an irregularity 27 in the road condition (e.g., pit) is observed in the front scanning area 39 of the vehicle 24. Because the vehicle 24 drives forward or intends to drive forward in the direction of travel 40, the path of the wheels can 29, 30, 31, 32 are determined. FIG. 4b it appears that the coinciding paths 33, 35 of the front wheel 29 and rear wheel 31 of the vehicle will encounter road irregularity 27 in the form of a pit. The controller 5 retrieves the road condition information and predicts the effect of the pit 27 on the CVT system 1 of the vehicle 24. If necessary (e.g. if the controller predicts that there is a risk of slip of the torque transferring part 17), the controller 5 of the CVT system 1 applies the clamping force or pressure of the at least one friction element 15, 16 to the torque transferring part 17. The risk is preferably assessed for each wheel 29, 30, 31 and 32 of the vehicle 24 based on predictions. However, it may be possible to employ a simplified embodiment where only the detection of the road condition in a scanning area is considered, regardless of the wheel tracks.

Alternatively or additionally, the controller 5 of the CVT system 1 may be arranged to work with probabilities for the wheel tracks 33, 35 and 34, 36.

FIG. 5a and 5b shows a schematic top view of a vehicle 24 and the surrounding area thereof. The vehicle 24 comprises a detector 38 which provides a front scanning area 39, which is formed by a projected field of view of the detector 38. In one example, the detector 38 can be an optical camera. When the vehicle travels in the direction of travel 40, it may encounter a region 44 with a noticeable change in the road roughness, for example due to snow on the road, another type of road, an object on the road, etc. The tracks 33, 34 of the front wheels 29, 30 of the vehicle 24 can be determined. The controller can predict the moment at which the front wheels will encounter the region 44 and, if deemed necessary, adjust the clamping force or pressure of the at least one friction element 15, 16 on the torque-transmitting part 17. It will be appreciated that the simplified embodiment where only the detection of the road condition in the scanning area is taken into account regardless of the wheel tracks is very effective in road conditions formed by water (rain), snow, gravel or similar scattered irregularities.

The controller 5 can determine a general road condition by using information from the detector 38 and a road type classification, the IRI classification and / or a road surface classification. The classification may already have been performed by the DIPCU. In one embodiment, the controller 5 can follow a range of approximately 20 meters in front of and behind the vehicle. Advantageously, the controller 5 is arranged to not change "fast" configurations of the clamping force or pressure in the variator for severe to less severe road conditions.

For example, if one frame (about 4 meters away) indicates that the road condition has improved considerably, then this must be confirmed a number of frames one after the other or for a certain distance traveled, before the previous configurations of the clamping force or pressure in the variator can are set to a new level. Image filtering can be applied to the images obtained from the camera. In an exemplary embodiment, the surface roughness can be classified into different classes, such as flat, asphalt, concrete, slightly hardened, strongly hardened, off-road, etc. Each class may require a different adjustment of the clamping force or pressure in the variator of the CVT system .

FIG. 5b shows a situation where the vehicle 24 initially moves in the direction of travel 40 and makes a right turn. In this example, the web 33 of one of the front wheels is shown. The controller 5 can be arranged to determine this path and to check whether the expected path will encounter a path condition that requires an adjustment of the clamping force or pressure of the at least one friction element 15, 16 on the torque-transmitting part 17. In this case a relevant road irregularity is detected. Although the predicted lane 33 does not encounter road irregularity 27, the controller may take into account possible changes in the lane represented by a first boundary lane 45 and a second boundary lane 46. Relevant road conditions detected in the zone between the first boundary lane 45 and the second boundary lane 46, which encloses the lane 33, can therefore be taken into account by the system to reduce and / or prevent the risk of push belt slippage in the variator 2. Alternatively or additionally, a region around a road irregularity can be increased by the controller to reduce and / or prevent the risk of push belt slip in the variator 2. It will be appreciated that the field of view of the detector 38 can be coupled to a steering direction of the wheels in order to, at least in general, look in the direction of the path of the vehicle.

FIG. 6 shows a side view schematic representation of a vehicle 24 comprising a CVT system 1 which is confronted with exemplary driving situations. Other scenarios are also possible. In the first case (a), the vehicle comprises a detector 38 which retrieves road condition information in a front scanning area 39 of the vehicle 24. The road condition information is analyzed and sent to the controller 5. In this case, a road irregularity 27 is detected, which is anticipated by the controller 5 for adjusting the clamping force or pressure of the at least one friction element 15, 16 on the torque transmitting part 17 in the variator 2 of the CVT system 1. Therefore, the controller 5 adjusts the clamping force based on the road irregularity 27.

Further, after passing the adverse road condition, the controller can adjust the clamping force based on new measurements in the forward direction 39, if the controller 5 has determined that the scanned upcoming road condition information provided by the detector 38 permits such a configuration.

In the second case (b) in FIG. 6, two vehicles 24, 47 both comprising a CVT system 1 with a detector 38 are shown. Both vehicles drive one behind the other in the direction of travel 40. There is sufficient distance between the two vehicles 24, 47 so that the detector 38 of the first vehicle 24 has the possibility of successfully scanning a front scanning area 39. The second vehicle 47 has detected a relevant road irregularity 27 in the front scanning area 39 thereof. The controller 5 of the second vehicle 47 can therefore adjust the clamping force or pressure of the at least one friction element 15, 16 on the torque-transmitting part 17 of the variator 2 of the vehicle 47 on the basis of the outdated arriving road condition information. If the direction of travel 40 is maintained, the first vehicle 24 will also encounter the road irregularity 27. The front scanning area 39 of the detector 28 of the first vehicle 24 has not yet reached the road irregularity. However, the second vehicle 47 can already wirelessly communicate upcoming road condition information assessed by the detector 38 of the vehicle 47 to the CVT system 1 of the first vehicle 24, before the irregularity 27 is detected by the detector 38 of the first vehicle 24. The wireless communication of the road condition can be performed directly, for example, by direct communication between the two vehicles 24, 47, or indirectly, for example via the internet or cloud protocols. It will be appreciated that the second vehicle can also transfer clamping force or pressure information to the first vehicle. This clamping force or pressure information is then representative of the road irregularity 27.

The third case (c) in FIG. 6 is similar to the second case (b). Here too, two vehicles 24, 47 are running one behind the other, both provided with a CVT system 1 and furthermore a detector 38 for detecting road conditions in the front scanning area 39 of the vehicle 24, 47. In this case the distance between the two vehicles is however, so that the viewpoint of the detector 38 of the first vehicle 24 is blocked by the second vehicle 47. Consequently, the detector of the first vehicle 24 is unable to obtain a front scanning area 39 of the ground 37 in front of the vehicle to obtain upcoming road information for the vehicle 24. In this case, the controller 5 of the vehicle 24 may not be able to assess the upcoming road condition so that if no other sources can provide the upcoming road information, the controller 5 of the vehicle 24 can preventively the clamping force or pressure of the at least one friction element 15, 16 on the torque transmitting part 17 of the variator 2 in the CVT system 1 To adjust.

Alternatively or additionally, the controller 5 of the first vehicle 24 can receive the road information from the vehicle 47, which has already scanned the road for the vehicle 24 without any limitation, and therefore the controller 5 of the vehicle 24 can receive based on the received the information adjusts the clamping force or pressure of the at least one friction element 15, 16 on the torque-transmitting part 17 of the variator 2 in the CVT system 1. Alternatively or additionally, in the case of an autonomous, self-driving or driving-assisted vehicle, the controller 5 of the first vehicle 24 may instruct a control system of the vehicle to increase the distance with the second vehicle 47, or in the case of a driver operated vehicle suggest that the driver increases the distance and / or inform the driver that the field of vision of the vehicle is blocked by the second vehicle 47. Also in this case, if possible, the second vehicle 47 can send road condition information to the first vehicle 24 , as in the second case (b).

In the fourth case (d) in FIG. 6, a first vehicle comprising a CVT system 1 drives behind a second vehicle 47, wherein the second vehicle 47 is an autonomous self-driving vehicle with one or more sensors 48 adapted to scan and assess a surrounding area of the vehicle 47. The one or a plurality of sensors 48 of the second vehicle 47 can provide a 360 ° view of the surrounding area, which can be used by the first vehicle 24 to obtain the road condition information. While in this case the detector 38 of the first vehicle 24 has not yet reached the road irregularity 27, the controller 5 of the first vehicle 24 can receive already relevant road condition information from the second vehicle 47. This illustrates inter-compatibility between different vehicles 24, 47 including different sensor systems 38, 48, respectively. Note that the second vehicle 47 may not include a CVT system 1. The communication between the vehicles can be realized directly or indirectly, for example by using a cloud.

In the fifth case (e) in FIG. 6, a vehicle 24 is shown comprising a CVT system 1, wherein the controller 5 is adapted to retrieve information representative of an upcoming road condition. The controller 5 (not shown) is adapted to adjust the clamping force or pressure of the at least one friction element 15, 16 on the torque transmitting part 17 in the variator 2 of the CVT system 1 on the basis of the obsolete path condition information. In this example, information about the road irregularity 27 relative to the vehicle 24 can be traced by using a local memory, cloud information and / or road condition information obtained by other vehicles or devices. For example, a GPS sensor can be used to determine the location and speed of the vehicle 24, wherein, as provided with upcoming road condition information, the controller controls the clamping force or pressure of the at least one friction element 15, 16 on the torque transferring member 17 can adjust if it is deemed necessary. For example, in this example, detailed upcoming road condition information may be available in a memory in the vehicle 24, or may be downloaded from a server, and the controller 5 may retrieve the upcoming road condition information. In addition, the controller 5 can link the upcoming road condition information with the location and speed of the vehicle to predict whether one or more of the wheels will encounter the road irregularity 27.

FIG. 7 shows a schematic representation of a control strategy for a CVT system. Certain environmental conditions 20 for a vehicle comprising a CVT system 1 may be useful for the operation and control of the CVT system 1. For example, an area of a road or ground on which a vehicle is or will be driven may be relevant for the control of the CVT. system 1. Therefore, the control strategy for the CVT system 1 will attempt to obtain the road condition information as predictive information using a, for example optical, feed device such as a camera as a detector, and / or information made available by wireless communication with a cloud. Advantageously, the optical feed device may be located on a front of the vehicle to provide at least one front scanning area for the vehicle. In addition, reactive information can also be obtained from other sensors such as a wheel speed sensor, hand pressure sensor, artificial horizon sensor and / or the steering angle sensor, used to improve the road condition information. The obsolete road condition information from the sensors and / or the cloud is then sent to the controller or TCU 5 of the CVT system 1.

According to the embodiment of FIG. 7, the controller 5 comprises two units, namely a clamping force calculating unit 22 adapted to determine and / or calculate the clamping force, and a pressure adjusting unit 23 adapted to generate the pressure setting commands. The controller 5 receives road condition information and can predict coupling peaks based on the information representative of the road condition. The hydraulic system is arranged to control friction elements based on the pressure setting commands coming from the controller 5. In this way the hydraulic system 6 can control the hydraulic pressure and / or the clamping force of the at least one friction element 15, 16 on the torque adjust transmission part 17 as a function of the predicted torque. In this example the control of the first friction element 15 can be directed to the clamping torque of the primary component of the variator while the control of the second friction element 16 can be directed to the clamping torque of the secondary component of the variator. The hydraulic system 6 can further be arranged for controlling other components of the CVT system 1.

All kinds of signals can be measured during contact of the wheels with a road irregularity or object on the road. For example, the event can be measured by using severity estimation sensors, such as internal speed sensors, handshake sensors, steering angle sensors, artificial horizon sensor, wheel speed sensors, accelerometers and / or accelerator demand sensors. Pattern recognition can be performed for identifying roads or road bumps. Other characteristics can be used, such as the fact that the location of the driver's foot of the vehicle can vary briefly depending on the vehicle movements. A more accurate determination of the road condition can be made based on this information. The measurements can be used to improve the quality of information on the road in the cloud by sending the information or a summary of this information to the cloud.

The required clamping force or pressure in the variator 2 can be calculated on the basis of a corrected general road condition, whereby the road condition signals can be coupled to a certain required clamping force or pressure level.

This can be calibrated for any type of vehicle 24 during the design and development of the CVT system 1.

The severity of the impact, the effect on the wheels, object classification, the required clamping force or pressure level, etc. can be based on calibrations, tests, drive models, and / or training (for example artificial intelligence). Drive models can predict the torque fluctuations on the driven shafts, and therefore the required clamping force or pressure levels.

In one embodiment, a general road condition estimate is obtained by using a camera. It is possible that the general road condition, for example about 20 meters around the vehicle, may include relevant features, such as a bad road surface, which are detected by the use of the camera, but are not recorded by the other sensors (cf. internal speed sensors, hand pressure sensor, steering wheel speed angle sensor, accelerometer and accelerator demand sensor). In this case, the expected / predicted road condition information may not fully correspond to the effects on the vehicle, so that the camera feed can be corrected by the measured estimate by the other sensors, depending on the reliability of the current feed.

Weather information can be useful for the required clamping force or pressure in the variator 2 of the CVT system 1. Road type classifications coming from the cloud can be reassigned to the classification used in this invention (e.g. IRI index, road surface, etc .). The available information about road objects, such as pits, curbs, etc. and their properties can be used by the controller 5 to predict possible impact. GPS location can be used to determine a precise location of the vehicle. GPS location of the vehicle can also be used for calibration, and for example updating in a storage such as the cloud, of known locations of the road irregularities. Road condition information from previous vehicles can be made available to the vehicle 24. The required clamping force or pressure in the variator 2, depending on a location, can be made available based on previous passages of the same vehicle or other vehicles that are capable of this. communicate information with vehicle 24 including the CVT system 1.

FIG. 8 shows a flow chart of a method according to the invention. The method can be used to operate the CVT system 1 for a vehicle 24, comprising the variator 2 with the first friction element 15 and the second friction element 16 coupled by the torque transmitting part 17. The method comprises a step of setting a clamping force or pressure of at least one friction element 15, 16 on the torque transferring member. The clamping force or pressure can be optimally or advantageously selected such that a reserve or safety margin which can have an adverse effect on the efficiency of the CVT system can be prevented or reduced. The method may further comprise a step of retrieving information representative of an approaching road condition, and a step of adjusting, based on the retrieved information, the clamping force or pressure of the at least one friction element 15, 16 on the torque transferring part 17. The method for operating a continuously variable transmission for a vehicle can be carried out at least in part by using dedicated hardware structures such as ASIC and / or FPGA components. Alternatively, the method may also be implemented at least in part with a computer program product comprising instructions to cause a processor of the computer system to perform the aforementioned steps of the method of the invention. Processing steps can in principle be performed on a single processor, in particular steps for retrieving upcoming road condition information. However, it is noted that at least one step can be performed on a separate processor.

The controller 5 can be arranged to receive traffic situation in the vicinity of the vehicle, which can be at least partially information representative of an upcoming road condition. The traffic situation information can be a general measure, such as little traffic, medium traffic and a lot of traffic. However, the traffic situation information may also include more detailed or specific data, such as positions and speeds of other road users (for example cars, cyclists, pedestrians, etc.), position of traffic lights and / or other characteristics that may have an impact on traffic. The controller 5 can be adapted to adjust the clamping force or pressure of the at least one friction element 15, 16 on the torque-transmitting part 17 on the basis of the outdated traffic situation information in combination, possibly together, with other outdated road condition information. It is also possible that the traffic situation information is based at least in part on a traffic prediction by a computer model. Moreover, the controller 5 can be designed to wirelessly retrieve said traffic situation from a network or cloud, an internal system in the vehicle and / or an external device (for example a smartphone).

The invention is described herein with reference to specific examples of embodiments of the invention. It will be understood, however, that various modifications and changes may be made therein without departing from the spirit of the invention. For clarity and concise description, features described herein are part of the same or separate examples or embodiments, however, alternative embodiments which have combinations of all or certain features described in these separate embodiments are also considered.

The CVT system 1 can be implemented in or take the form of a vehicle 24. Alternatively, the CVT system 1 can be implemented in or take the form of other vehicles, such as cars, recreational vehicles, trucks, buses, motor scooters, bicycles, motorcycles, scooters, lawn mowers, agricultural vehicles, construction vehicles, golf carts, trolleys and robotics vehicles. Other vehicles are also possible. The embodiments shown concern four-wheeled vehicles, but vehicles with a different number of wheels can be used, such as, but not limited to, tricycles, three-wheeled vehicles, quads, motorcycles, trucks, vehicles comprising trailers, etc. Moreover, the CVT system 1 are used in vehicles coupled to a trailer, trailer, lorry, etc., whereby optionally the wheels of the trailer and / or trailer can be considered as additional wheels of the vehicle by the CVT system 1. The CVT system 1 can be arranged to to take into account wheels of other coupled vehicles in the same manner as the wheels of the vehicle comprising the CVT system 1. It is also conceivable that a multiple number of CVT systems 1 are included in a vehicle.

FIG. 9 shows a schematic representation of an example of a control strategy for a CVT system 1. The road condition can be checked by using a camera and a cloud for retrieving information representative of the road condition information. Additionally, other sensors can also be used to obtain a better prediction of the road condition information and / or improve available road condition information, for example in a memory and / or a cloud. In the controller or TCU 5, a distinction is made between a general road condition and the local road condition. Information representative of the road condition obtained with the camera and / or the cloud can be used by the TCU 5 to obtain both local road condition information and general road condition information. Information retrieved by other sensors can be used by the TCU 5 to build up a general road condition information. On the basis of the obsolete general and local road condition information, the TCU 5 is adapted to adjust the clamping force or pressure of the at least one friction element on the torque-transmitting part 17. From the obtained general road condition the severity of the impact can be estimated or determined by the TCU 5. The severity of the impact can also be estimated or determined by the TCU 5 by using the obtained local road condition information. However, the local road condition information can be used to predict the moment of impact. The severity of the impact and the moment of the impact allow the TCU 5 to perform a clamping force calculation, whereby the result of the calculation or estimate can be used to provide a clamping pressure (ie pressure setting) of at least one friction element 15, 16 to adjust the torque transmitting part 17. The pressure setting is used to control the hydraulic drive system 6 of the CVT system 1, wherein the hydraulic drive system 6 has a first hydraulic pressure line 7 which is connected to the first friction element 15 and a second hydraulic pressure line 8 which is connected to the second friction element 16 The hydraulic pressure in the first hydraulic pressure line 7 provides a first clamping force on a first frictional element of the variator 2, and the hydraulic pressure in the second hydraulic pressure line 8 provides a second clamping force on a second frictional element of the variator 2.

In the embodiments shown, the clamping force is supplied by a hydraulic drive system 6. However, other embodiments may include drive by means of mechanical, electromechanical or electro-hydraulic systems.

The engine or power tool 11 of the vehicle 24 comprising the CVT system 1 according to the present invention can be or comprise any combination of a combustion engine and an electric motor. Other engines are also possible, such as a fuel cell engine. In some embodiments, the motor 11 may comprise multiple types of power tools and / or motors. For example, a fuel-electric hybrid car can include a gasoline engine and an electric motor. Other examples are possible.

As to the torque transferring member, a number of embodiments are described herein including a push belt type variator. However, different types of belts for CVTs are known, such as dry belts, chain belts and push belts, which can be used for the invention according to the present application. Other types of CVT systems are also disclosed herein, the torque of which is transmitted based on frictional elements controlled by one or more clamping forces, which may be toroidal, ratchet, cone, or other types of CVT.

It will be appreciated that the method may include computer implemented steps. All the above steps can be computer implemented steps. Embodiments may include computer devices, with processes being performed in computer devices. The invention also relates to computer programs, in particular computer programs on or in a carrier, adapted to put the invention into practice. The program may be in the form of source or object code or any other form suitable for use in carrying out the processes according to the invention. The carrier can be any entity or device capable of carrying the program. For example, the carrier may comprise a storage medium, such as a ROM, for example a CD-ROM or a semiconductor ROM, or a magnetic recording medium, for example a floppy disk or a hard disk. Furthermore, the carrier can be a transferable carrier, such as an electrical or optical signal which can be transmitted via electrical or optical cable or by radio or other means, for example via the internet or the cloud.

Some embodiments may be implemented, for example, using a machine or tangible computer-readable medium or object that may store an instruction or set of instructions which, when executed by a machine, may cause the machine to process and / or process performs in accordance with the embodiments. Such a machine may comprise, for example, any suitable processing platform, computer platform, computer device, processing device, computer system, processing system, computer, processor, or the like, and may be executed using any suitable combination of hardware and / or software. The machine-readable medium or object can comprise, for example, any suitable type of memory unit, memory device, memory article, memory medium, storage device storage article, storage medium and / or storage unit, for example, memory, removable or non-removable media, erasable or non-erasable media , writable or rewritable media, digital or analogue media, hard disk, floppy disk, Compact Disk Read Only Memory (CD-ROM), Compact Disk Recordable (CD-R), Compact Disk Rewritable (CD-RW), optical disk, magnetic media, magneto-optical media, removable memory cards or disks, various types of Digital Versatile Disk (DVD), a tape, a cassette or the like. The instructions may include any suitable type of code, such as source code, compiled code, interpreted code, executable code, static code, dynamic code, encrypted code, and the like executed using any suitable high-level, low-level, object-oriented , visual, compound and / or interpreted programming language.

Different embodiments can be implemented using hardware elements, software elements, or a combination of both. Examples of hardware elements can be processors, microprocessors, circuits, application specific integrated circuits (ASIC), programmable logic devices (PLD), digital signal processors (DSP), field programmable gate arrays (FPGA), logic gates, semiconductor device registers, microchips, chipsets, etc. Examples of software can be software components, programs, applications, computer programs, software programs, system programs, machine programs, operating system software, mobile apps, middleware, firmware, software modules, routines, subroutines, functions, computer implemented methods, procedures, software interfaces, application program interfaces (API), methods, instruction sets, data processing code, computer code, etc.

The graphic and / or photo / video processing techniques can be implemented in various hardware architectures. Graphical functionality can be integrated in a chipset. Alternatively, a discrete graphics processor can be used. For example, image processing (photo or video) can be performed by a graphic subsystem such as a graphic processing unit (GPU) or a visual processing unit (VPU). As yet another embodiment, the graphic or image / video processing functions can be performed by a general purpose processor, including, for example, a multi-core processor. In a further embodiment, the functions can be implemented in a consumer electronics device. Versions with a combination of different hardware platforms are possible.

In various embodiments, the controller can communicate via wireless systems, wired systems, or a combination of both. When implemented as a wired system, the system may include components and interfaces suitable for communication, or wired media, such as input / output (I / O) adapters, physical connectors to connect the I / O adapters to a correspondingly wired communication medium. When implemented as a wireless system, the system may include system components and interfaces suitable for communication via a wireless shared medium, such as one or more antennas, transmitters, receivers, transceivers, amplifiers, filters, control logic, etc. An example of a wireless shared medium can include parts of a wireless spectrum, such as the RF spectrum, etc. A wireless communication device can be included to transmit signals and receive via various suitable wireless communication techniques. Such techniques can involve communication on one or more wireless networks. Examples of wireless networks include, but are not limited to, cellular networks, wireless local networks (WLANs, cf. WiFi), wireless personal area networks (WPANs), wireless metropolitan area network (WMANs), satellite networks, etc. Such networks allow the sender to operate in accordance with one or more applicable standards in any version.

The invention is described herein with reference to specific examples of embodiments of the invention. It will be understood, however, that various modifications, variations, alternatives, and modifications may be made therein without departing from the essence of the invention. For clarity and concise description, features are described herein as part of the same or separate embodiments, however, alternative embodiments that include combinations of all or part of the features described in these individual embodiments have also been considered and are understood to be within the scope. fall of the invention as indicated by the claims. The specifications, figures and examples should therefore be considered in an illustrative sense rather than a restrictive sense. The invention is intended to cover all alternatives, modifications and variations that fall within the spirit and scope of the appended claims. Furthermore, many of the elements described are functional entities that can be implemented as discrete or distributed components or together with other components, in any suitable combination and location.

In the claims, all reference characters in parentheses should not be interpreted as limiting the conclusion. The word "comprising" does not exclude the presence of elements or steps other than those mentioned in a claim. Furthermore, the words "one" and "one" should not be construed as being limited to "only one," but instead be used to mean "at least one," and not exclude a multiple number. The mere fact that certain measures are enumerated in mutually different claims does not indicate that a combination of these measures cannot be used as an advantage

Claims (33)

CONCLUSIONS A continuously variable transmission for a vehicle, comprising: a variator with two frictional elements, wherein a first frictional element is coupled to a second frictional element by a torque-transmitting part, wherein a clamping force or pressure of at least one frictional element is adaptable to the torque-transmitting part is; a controller adapted to retrieve information representative of an upcoming road condition; wherein the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the torque-transmitting part on the basis of the outdated information. Continuously variable transmission system according to claim 1, wherein the controller is adapted to predict a change in the input and / or output torque of the variator on the basis of the retrieved information, and to adjust the clamping force or pressure of the variable least one friction element on the torque-transmitting part according to the predicted torque change. Continuously variable transmission system according to claim 1 or 2, wherein the controller is adapted to predict a moment when the input and / or output torque of the variator changes based on the information found, and adjust the clamping force or pressure of the at least one friction element on the torque transferring member according to the predicted torque change. Continuously variable transmission according to claim 2 or 3, wherein the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the torque-transmitting part as the predicted change in the input and / or output torque of the variator exceeds a predetermined threshold value. Continuously variable transmission according to any of the preceding claims, wherein the controller is adapted to retrieve information representative of the road condition of a detector for detecting a road condition. Continuously variable transmission according to any one of the preceding claims, wherein the detector is adapted to determine the road condition before the vehicle. Continuously variable transmission according to any one of the preceding claims, wherein the detector is placed in the vehicle. A continuously variable transmission according to any one of the preceding claims, wherein the controller is adapted to be wirelessly connected to the detector. Continuously variable transmission according to claim 8, wherein the controller is adapted to communicate with the detector, the detector being placed in a further vehicle, which preferably runs in front of the vehicle with the continuously variable transmission system. Continuously variable transmission according to claim 8 or 9, wherein the controller is adapted to communicate with the detector, the detector being placed stationary with respect to the road. A continuously variable transmission according to any one of the preceding claims, wherein the controller is adapted to communicate with a network for retrieving the road condition information. The continuously variable transmission according to claim 11, wherein the network comprises a memory which stores the road condition information. Continuously variable transmission according to claim 11 or 12, wherein the network communicates with one or more detectors arranged for determining the road condition, the one or more detectors being stationary with respect to the road and / or in vehicles. A continuously variable transmission according to claim 11, 12 or 13, further comprising a network server adapted to provide road condition information to the controller. The continuously variable transmission according to claim 14, wherein the network server is adapted to receive from the controller an indication of a location of the controller, and to transfer road condition information about the location of the controller to the controller. A continuously variable transmission according to any one of the preceding claims, wherein the detector comprises an optical system, such as a digital camera, a radar system, a lidar system, and / or an acoustic system. Continuously variable transmission according to claim 16, wherein the controller is adapted to analyze an image provided by the camera, for features indicative of the road condition. A continuously variable transmission according to any one of the preceding claims, wherein the system further comprises a wheel speed sensor, and the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the part further on the basis of the detected wheel speed. A continuously variable transmission according to any one of the preceding claims, wherein the system further comprises a hand pressure sensor, and the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the part further on the basis of the detected hand pressure. A continuously variable transmission according to any one of the preceding claims, wherein the system further comprises an artificial horizon sensor, and the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the part further on the basis of the detected horizon . A continuously variable transmission according to any one of the preceding claims, wherein the system further comprises a steering angle sensor, and the controller is adapted to adjust the clamping force or pressure of the at least one friction element on the part further on the basis of the detected steering angle. A continuously variable transmission according to any one of the preceding claims, wherein the system is arranged to supply variable outgoing speeds and torques to one or more wheels coupled to the system, the outdated information representative of the road condition being used to estimate an estimated interaction of at least determine at least one of the one or more wheels with an approaching road. The continuously variable transmission of claim 22, wherein a plurality of wheels are coupled to the system for which an estimated interaction with oncoming road is determined, wherein the estimated interaction is determined together or separately. Continuously variable transmission according to claim 22 or 23, wherein the controller is arranged to recognize when one or more additional wheels are coupled to the system, the outdated information representative of the road condition being further used to achieve an estimated interaction of at least to determine one of the additional wheels with an approaching road. A vehicle comprising a continuously variable transmission according to any of claims 1-24. The vehicle of claim 25 further comprising the detector. A network server adapted to transfer information representative of a road condition to a vehicle with a continuously variable transmission according to any of claims 1-24. A network server according to claim 27, adapted to receive information representative of a road condition from one or more sensors. A network server according to claim 27 or 28, adapted to receive information representative of a road condition and / or a clamping force or pressure of a vehicle. A network server according to any one of claims 27-29, adapted to receive from a vehicle an indication of a location of the vehicle, and to transfer to the vehicle information representative of the road condition at and / or near a location of the vehicle. A network server according to any one of claims 27-30, with a memory coupled thereto which stores information representative of road conditions. A method for operating a continuously variable transmission system for a vehicle, comprising a variator with a first friction element and a second friction element coupled by a torque transmitting member, the method comprising: adjusting an optimum clamping force or pressure of at least ten at least one friction element on the torque transferring member; retrieving information representative of an upcoming road condition; on the basis of the information retrieved, adjusting the clamping force or pressure of the at least one friction element on the torque-transmitting part. 33. A computer program product for operating a continuously variable transmission system for a vehicle, comprising a variator with a first friction element and a second friction element coupled by a torque transmitting member, the computer program product comprising instructions for causing a processor to perform the steps : providing a signal for adjusting an optimum clamping force or pressure of at least one friction element on the torque-transmitting part; receiving information representative of an upcoming road condition; and providing a signal for adjusting the clamping force or pressure of the at least one friction element on the torque-transmitting member, based on the outdated information.