Patent Publication Number: US-2021188230-A1

Title: Assembly and method for a vehicle

Description:
The present invention relates to an assembly and a method for operating a vehicle or a plurality of vehicles. 
     BACKGROUND 
     In road traffic and in various other applications, such as at airports, it is both for safety and for operational efficiency useful to have knowledge of various environmental aspects relating to roads, runways, pavements, etc. For example, energy consumption, noise, air pollution, actual rolling resistance and other properties can be relevant. These and other factors may apply to all types of wheels of vehicles, which are moving on a roadway. 
     Documents which may be useful for understanding the background include U.S. Pat. Nos. 4,958,512, 4,098,111 and 6,923,038. 
     For example, rolling resistance that arises during driving and braking is a result of very complex mechanisms, which are influenced by many factors, for example the surface of the ground, the velocity of the vehicle, air temperature, the design of the tyres, the quality of the tyres and not least whether there is water, mud, snow or ice on the ground. Even with apparently similar conditions, the rolling resistance can vary significantly, for example it can be mentioned that water whipped with air has very different properties compared to water which is not mixed with air. This last condition is one that has traditionally not been aware of and taken it into account. 
     It is therefore desirable to provide new systems and techniques for measuring of rolling resistance or other parameters associated with vehicles and/or drive surfaces to a greater accuracy. 
     SUMMARY 
     In an embodiment, there is provided an assembly comprising a vehicle having a plurality of wheels, each of the wheels arranged to support a weight of the vehicle against an underlying surface; a sensor operable to measure a force between one of the wheels and a body of the vehicle; and a processor configured to receive measurement data from the sensor. 
     In an embodiment, there is provided a method for measuring conditions of a drive surface, the method comprising: driving a vehicle having an assembly according to any preceding claim on the surface; logging a series of force measurements from the sensor. 
     In an embodiment, there is provided a method of operating vehicles on a road, the method comprising: obtaining a road condition parameter from a sensor at a first vehicle; and transmitting the road condition parameter and a geographical location parameter, the geographical location parameter being representative of the location at which the road condition parameter was obtained, to a central computing system. 
     The appended dependent claims and the detailed description below outline further embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The above and other characteristics will become clear from the following description of illustrative embodiments, given as non-restrictive examples, with reference to the attached drawings, in which: 
         FIG. 1  shows the device according to the invention arranged on a rig carrying a wheel, seen from the side, 
         FIG. 2  shows the device of  FIG. 1  seen from ahead, 
         FIG. 3  shows the device of  FIG. 1  seen from above, 
         FIG. 4  shows the device of  FIG. 1  mounted in front of a vehicle, 
         FIG. 5  illustrates rolling resistance, 
         FIG. 6  illustrates components of an embodiment, 
         FIG. 7  illustrates components of an embodiment, and 
         FIG. 8  illustrates a method according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Various parameters relating to vehicles or drive surfaces, such as roads, may be relevant for capturing, analysis and use with systems and methods as described herein. 
     In relation to measurement of rolling resistance, there may be large differences in the way that water affects the measuring devices. Water falling for instance as rain during sampling, is quite different from water lying still on the road. Likewise the quantity of water (the depth) is of great importance regarding rolling resistance. Use of the present invention makes it possible to eliminate a number of usually occurring uncertainty factors, in that values can be read off directly on a monitor without converting external data regarding the condition of the road, tyres, water density and so on. 
       FIG. 1  shows a device according to an embodiment mounted in a rig, the rig carrying a wheel, as seen from the side. The rig can be attached to the front of a vehicle.  FIG. 2  shows a front view of the same device, and  FIG. 3  a top view.  FIG. 4  shows the device arranged on a vehicle  13 . The device comprises a bracket or fastening plate  1  on which the device is secured on one side, and on the other side the plate  1  is secured to the vehicle  13 . As shown in  FIG. 4 , the device is located in front of the vehicle  13 . 
     The device comprises at least one wheel  2  that preferably by means of its own weight impinges the ground  5 . In the wheel  2  is a nave  4 . The wheel  2  can freely rotate around the nave  4 , without brakes. 
     The suspension of the wheel  2  comprises a vertical holder  3  that is supported in the upper edge and may pivot around this point  7  as a pendulum. The arm  8  is also movable around its supporting locality  9  that has its attachment in the plate  1  which is secured to the vehicle  13 . 
     To avoid that the vertical holder is getting out of its precise position during driving, it is equipped with an adjusting screw  6  located on a pendant arm  11  which provides that it does not loosen. The vertical holder may to a certain degree move up and down, such that the wheel  2  is always in touch with the roadway with a downwards pressure. The downwards pressure may be provided by the weight of the wheel  2  and the holder  3 . The wheel  2  may also be provided with a spring that keeps the wheel towards the roadway with a constant pressure. 
     When the vehicle  13  is moving forward, there will arise a force from the wheel  2  toward the vehicle  13 , illustrated with an arrow  14 . A measuring cell  10 , which is installed on the permanent pendant girder  12  from the bracket  1  receives and measures this force. 
       FIG. 5  illustrates the rolling resistance of the wheel  2  moving on a surface  5 . The wheel  2  rotates as indicated by the arrow  2 ′. A part of the rolling resistance is the deformation of the surface and the wheel. In addition, as the wheel  2  moves on the surface  5 , an amount of liquid  21 , such as water or mud, will be displaced by the wheel  2 , thus creating a hydraulic force  23  in the direction of the nave  4 . The resistance of the forward motion creates a force on the nave  4 , the force having a horizontal force component Fx  20 , a vertical force component Fy  22  and a perpendicular force component Fz, not shown. The horizontal force component Fx is as illustrated by arrow  20  acting backwards. The forces acting on the nave  4  can be measured by the load cell  10  (see  FIG. 1 ). 
     From the sensor  10  there is a connecting line or a wireless connection to a processor  15  inside the driver&#39;s cab, which displays the force on a monitor display. 
     In one embodiment, the measured force can be stored on a computer system and/or transmitted to a remote location. The measured force may be transmitted in real time. The force can be calibrated in relation to a measured speed of the vehicle  13 . The speed of the vehicle  13  can be measured by a tachometer associated with the wheel  2  and/or a tachometer within the vehicle  13 . 
     The measurements can be performed by setting a fixed, substantially constant velocity of the vehicle  13 , or by obtaining measurements at different speeds of the vehicle  13 . Measuring at different speeds may provide improved knowledge of the road conditions, since certain aspects associated with the measured parameters may be highly non-linear in nature. Obtaining readings at different measurement points may thus provide improved accuracy. 
     To obtain the data, the vehicle  13  drives on the roadway, and it is possible to read on the display the rolling resistance, or the measured values for this can be logged locally or remotely. Optionally, other parameters can be measured, such as acceleration. Data relating to rolling resistance, noise emission, skid resistance, surface texture, other safety issues, energy consumption, or other aspects may then be displayed and/or stored. 
     The device can be located in front of the vehicle  13 . This allows the device to measure the conditions of a surface that has not been disturbed by the vehicle  13 , and avoids other influence of the vehicle  13  on the measurements. 
     The obtained data can be coordinated and converted to units that can be compared from time to time, or continuously. Measurements from different times may then be compared to identify, for example, a deterioration of the surface  5 . 
     The wheel  2  and associated components may be secured to the bracket  1  with a quick release coupling, to ease the use of the device. Alternatively, the bracket  1  may be releasable from the vehicle  13  in the same way. 
     As described above, the wheel  2  is suspended in a link which may pivot to some degree in the vertical plane, in order to absorb minor unevenness on the roadway. 
     In one embodiment, the sensor  10  may be arranged on at least on of the regular wheels of the vehicle  13 , each of the wheels  2  arranged to support a weight of the vehicle  13  against the underlying surface  5 . Having the sensor  10  on any of the front wheels of the vehicle  13  allows the device to measure the conditions of a surface that has not been disturbed by the vehicle  13 . The sensor  10  may then measure the horizontal force component Fx acting between the wheel  2  and the body of the vehicle  13 , for example a force representative of the rolling resistance of the road or underlying surface  5  as the vehicle  13  drives; the vertical force component Fy acting between the wheel  2  and the body of the vehicle  13 ; a perpendicular force component Fz acting between the wheel  2  and the body of the vehicle  13 ; a combination of these; and/or forces acting in different directions. 
     The processor  15  can receive the measurements and store these, process them, transmit them further, etc. 
     The sensor  10  may be a load cell configured to measure a force acting from the wheel  2  on the vehicle  13  in the vehicle&#39;s direction of travel, i.e. horizontally, in a vertical direction, or in other directions.  FIG. 6  illustrates an example of a sensor  10  suitable for use with embodiments described herein. The sensor  10  in this embodiment is arranged around a bearing  40  which supports one of the wheels  2  of the vehicle  13 . The sensor  10  measures a force Fx in the horizontal direction and a force Fy in the vertical direction acting between the wheel  2  and the body of the vehicle  13 . The sensor  10  may, alternatively or in addition, measure other forces, i.e. such forces which act in different directions compared to the horizontal or vertical. 
     The sensor  10  may be a single sensor measuring a plurality of forces, direction and magnitude, working on the nave  4 . The sensor  10  may be made up of a plurality of individual sensor units, each sensor unit measuring a force in one particular direction. 
     The readings from the sensor  10  may be sent to a display on the processor  15  for displaying to a driver or another operator in the vehicle  13 , and/or it may be transmitted to a location external to the vehicle  13  via a data transmitter  41 . The data transmitter  41  may, for example, be a wireless communication device such as a GSM device, a WLAN device, or a Dedicated short-range communications (DSRC) device. The wireless communication device could for example be an Intelligent Transport Systems (ITS) device. 
     In one embodiment, the processor  15  is operable to determine a condition where the vehicle is about to experience loss of traction and display a warning to the driver or another operator of the vehicle. In one example, the processor may determine that the vertical force component Fy, due to liquid on the surface  5 , is about to exceed the weight of the wheel  2 , a condition known as hydroplaning or aquaplaning. 
     In one embodiment, the processor  15  is operable to transmit the measurement data from the sensor  10  to a receiver  30  outside the vehicle  13 . The receiver may be, for example, a central computing system  30  located at a remote location, such as a data centre, with which the processor  15  is connected via wireless data transfer. In this way, the measurement data may, for example, be transferred “to the cloud”, for further processing or use by others. The transfer of the measurement data may be done in real time. This is illustrated schematically in  FIGS. 7 and 8 , with the arrows indicating transfer of data to and/or from a plurality of vehicles  13   a - d  driving on a road  5 . 
     Optionally, a series of geographical coordinates, such as GPS readings, may be transmitted together with the measurement data, such that each geographical coordinate corresponds to a respective force measurement. In this way, a map of the road conditions (for example, rolling resistance or friction) across a length of road or surface  5  can be obtained. This map can be used by others to analyze road conditions, for operational planning (e.g. road maintenance), or to provide safety-related data to the vehicle  13  and/or other vehicles  13   a - d.    
     In an embodiment, measurement data from several vehicles  13   a - d  can be transmitted to the central computing system  30 . This may provide more complete information about road conditions, with higher granularity, and more accurate information, in that independent measurements is available and available for direct use or, for example, for trending/forecasting. 
     In an embodiment, a method according to the invention can be used to transmit data back from the central processing system  30  to one or more of the vehicles  13   a - d . For example, a surface condition parameter can be calculated, the surface condition parameter being determined on the basis of several force measurements and being representative of the rolling resistance of the road or surface  5  at different locations. This may comprise, or be supplemented by, corresponding geographical location data. In this way, vehicles  13   a - d  may receive information on road conditions ahead, which may be relevant for safety or for energy consumption. For example, electric vehicles may in such a case provide more accurate predictions on the available driving range, by taking into account actual road conditions. Or, specific road location with increased safety risks may be identified and information relating to these may be provided to vehicles  13   a - d  approaching it. One example of this may be locations with wet roads with increased risk of aquaplaning. By providing information on this to the vehicle  13   a - d  and/or to the driver, the risk of accidents can be reduced. 
     Embodiments of the present invention may be particularly useful in cold climates, such as in regions with snow, ice and mud-covered roads. In such cases, vehicle energy use may vary significantly according to road conditions, and there are also increased requirements for road maintenance (e.g. snow clearing). Nevertheless, embodiments described herein can be useful in any location. 
     Road friction may, for example, be measured in the same way as described in U.S. Pat. No. 6,923,038 B2, by measuring the maximum horizontal force Fx obtained during driving. 
     In one embodiment, there is provided a method of operating vehicles  13   a - d  on a road  5 , the method comprising obtaining a road condition parameter from a sensor  10  at one vehicle  13   a - d ; and transmitting the road condition parameter and a geographical location parameter to a central computing system  30 . The geographical location parameter is representative of the location at which the road condition parameter was obtained. The central computing system  30  is thus provided with actual and current information on the road condition at that location. 
     The road condition may be a measured friction between the wheel  2  and the road  5 , a measured rolling resistance of the wheel  2  on the road  5 , an identified damage to the road  5 , such as damage to the asphalt, or an indicator for a road maintenance requirement. The latter may be, for example, a level of snow or ice which requires clearing snow from the road  5  or gritting the road  5 . This information may be provided to a central location where road management personnel monitor the state of the road  5  and may take action as necessary. By means of the method, a more accurate maintenance of the road  5  is achieved, with a shorter response time for personnel to take action when necessary, and/or avoiding for example unnecessary gritting. 
     Advantageously, one can use the method to obtain road condition parameters from a plurality of sensors  10  arranged at different vehicles  13   a - d . This improves accuracy and granularity. In an ideal scenario, one might envisage a large number of vehicles, or even substantially all vehicles travelling on a particular road  5 , to obtain road condition parameters and transmit these to the central computing system  30 . 
     Having information on road conditions at a given location, the method may further comprise performing a road maintenance action at the location. 
     In one embodiment, the method comprises transmitting road condition data from the central computing system  30  to a second vehicle  13   a - d , where the road condition data comprises information on a road condition on at least one location of the road  5 . This can be, for example, a site with icy road surface which poses a safety risk. Information about this site from the central computing system  30  may then be transmitted to a vehicle  13   a - d  approaching the location, as a warning for the driver or for the vehicle drive system. 
     The sensor arrangement on the (or each) vehicle  13   a - d  may be any of those described above and illustrated in  FIGS. 1-6 . For example, the sensor  10  can be arranged between a wheel  2  of the vehicle  13   a - d  and a wheel suspension  3 , 12 , similar to that shown in  FIG. 1 , or between a bearing  40  and the body of the vehicle  13   a - d  as illustrated in  FIG. 6 . In another example, the sensor  10  is integrated in one of the regular components of the vehicle  13   a - d . Alternatively, a different type of sensor may be used, such as a visual sensor, a camera, an acceleration sensor which registers the vehicle&#39;s dynamics, a wheel spin sensor which registers loss of traction or discrepancies between different wheels of the vehicle  13   a - d , or other types of sensors. 
     According to embodiments described herein, recording rolling resistance data or other data in a reliable, easy and safe way is made possible. Other relevant data may be, for example, noise emission, skid resistance, surface texture, other safety issues, energy consumption, etc, according to given requirements. The data can be converted and displayed on a monitor for instance in the drivers cabin of a vehicle or transmitted to a remote location. In this way it is possible to read the correct values and they will give the actual parameters of the carriageway. This can then be used, for example, for planning of road maintenance. In some embodiments, the apparatus and method can be used to achieve improved safety. 
     The invention is not limited by the embodiments described above; reference should be had to the appended claims.