SE1650310A1 - Measuring Device for Assessing a Torque Parameter of a Vehicle and Method for Assessing a Torque Parameter of a Vehicle - Google Patents

Abstract

Herein a measuring device (2) for assessing a torque parameter of a vehicle comprising a first yoke (4), a second yoke (6), a universal joint cross (8), and an axle (10) having a first end portion (12) and a second end portion (14). A torsion sensor (18) is attached to the first end portion (12). Further, herein a method for assessing a torque parameter of a vehicle is disclosed.Elected for publication: Fig. 1A

Description

1 l\/leasuring Device for Assessing a Torque Parameter of a Vehicle andMethod for Assessing a Torque Parameter of a Vehicle TECHNICAL FIELD The present invention relates to a measuring device for assessing a torque parameter of avehicle and a method for assessing a torque parameter of a vehicle. The present inventionfurther relates to a computer program and to a computer program product.

BACKGROUND A torque of a drive unit, such as an internal combustion engine and/or a transmission,transmitted to at least one drive wheel of a vehicle may be assessed in different ways and forvarious purposes. The torque may be assessed via the amount of fuel injected into aninternal combustion engine of the drive unit, via calculation based on vehicle weight andvehicle acceleration, or measured utilising various sensors. The torque may be e.g.assessed for controlling gear shifting in the transmission, for controlling vehicle speed, or forverifying torque performance of the drive unit or other parts of a powertrain of the vehicle.

GB 1309892 discloses torque transducers. The torque transmitted by a shaft is measured byresistance strain gauges located on a reduced diameter portion of the shaft, which is coveredby a stiff sleeve member. The signal from the strain gauges is taken out by slip rings securedto the sleeve.

GB 918338 discloses a torque transducer of the type having strain gauges mounted tomeasure the twist of a shaft transmitting the torque. A slip ring assembly is detachablymounted over the portion of the shaft to which the strain gauges are attached. A shaft has aportion of reduced diameter to which the resistance strain gauges are attached. Theconnections to the strain gauges are taken via a channel in the shaft to a plug in a flangeattached to the shaft. The slip ring assembly comprises a sleeve having a flange carrying asocket to mate with a plug. The flange being secured to a flange of the shaft, by screws. Thesleeve carries a plurality of ring electrodes which dip into pools of mercury carried inchambers formed in the block which is rotatably mounted on the sleeve by means ofbearings. The plug is connected to metallic parts of the mercury chambers to establishelectrical contact, via the mercury, with the electrodes which are in turn connected via plugand socket with the strain gauges. 2 WO 0208048 discloses a rotatable assembly for a vehicle road wheel and includes a vehiclesuspension knuckle, a drive shaft, a first bearing carried by the knuckle for rotatablysupporting the drive shaft, a wheel hub drivingly connected to the drive shaft, a brake discsupport rotatably carried by the first bearing and connected to the drive shaft to rotatetherewith. The connection between the brake disc support and the drive shaft beingseparated and spaced apart along the shaft from the connection between the drive shaft andthe wheel hub. A second bearing between the wheel hub and the brake disc supports thewheel hub and allows relative rotation between the brake disc support and the wheel huband a torque sensor. The torque sensor is arranged between said connections to sense thetorque or the change in torque being transmitted by the drive shaft to the wheel. Themeasured torque signals may be used as a primary source of information for ABS and/ortraction control but could also be used to control automatic gear boxes for smooth gearshifts.

US2010200325 discloses a drive shaft assembly with a toque sensor. The driveshaftassembly includes a first shaft member, a second shaft member, a bearing assembly and asensor. The first shaft member has a magnetically encoded zone with a magnetic field thatvaries as a function of the torque that is transmitted through the first shaft member. Thesecond shaft member is coupled for rotation with the first shaft member. The bearingassembly comprises a bearing support, which is configured to be coupled to a vehiclestructure, and a bearing that is housed in the bearing support. The bearing supports the firstshaft member for rotation about a first axis. The sensor is coupled to the bearing assembly.The sensor is arranged to sense the magnetic field of the magnetically encoded zone andresponsively produce an electrical signal. lndirectly assessing the torque of a drive unit may be sufficient in many situations, i.e.estimating or calculating a torque using related parameters such as amount of fuel injected,or vehicle weight and vehicle acceleration. However, under some circumstances suchindirect methods are not precise enough, and at least one torque parameter of a drive train ofa vehicle has to be measured, e.g. for diagnosing vehicle behaviour, or for calibrating one or more vehicle functions.

SUMMARY lt is an object of the present invention to provide a measuring device for assessing a torqueparameter of a vehicle, which may be utilised for occasional precise torque assessment in avehicle. 3 According to an aspect of the invention, the object is achieved by a measuring device forassessing a torque parameter for a vehicle comprising a first yoke, a second yoke, auniversal joint cross, and an axle having a first end portion and a second end portion. Thefirst and second yokes are connected to each other via the universal joint cross. The firstyoke is connected to the first end portion of the axle. The second end portion of the axle isprovided with splines. The second yoke is configured for connection to a powertrain of avehicle. The second end portion of the axle forms part of a slip joint. The measuring devicefor assessing a torque parameter for a vehicle comprises a torsion sensor attached at thefirst end portion.

Since the measuring device for assessing a torque parameter for a vehicle is designed in theform of a universal joint and comprises splines arranged at the second end portion of theaxle, the measuring device is configured to replace an ordinary universal joint arrangement ina powertrain of a vehicle for the purpose of assessing a torque parameter in the vehicle.Moreover, since the measuring device comprises a torsion sensor, precise torquemeasurements in the vehicle powertrain may be provided. As a result, the above mentionedobject is achieved. ln particular, as the second end portion comprising splines forms part of a slip joint, themeasuring device for assessing a torque parameter of a vehicle may be connected with apropeller shaft of the powertrain, wherein an end portion of the propeller shaft forms a matingpart of the slip joint. Thus, the ordinary universal joint arrangement may be easily demountedfrom the vehicle by detaching a second yoke of the universal joint arrangement from thepowertrain and simply sliding apart a slip joint with the propeller shaft in order to thereafterslide the splines of the measuring device onto the propeller shaft and attach the second yokeof the measuring device to the powertrain.

One advantage with designing the measuring device for assessing a torque parameter of avehicle as a universal joint arrangement is that universal joint arrangements are largelyharmonised design elements of vehicles. Thus, one vehicle manufacturer may use the sametype of universal joint arrangement in a number of different vehicle models, whereas otherparts of the powertrain have to be manufactures vehicle model specific. Accordingly, if ameasuring device for assessing torque in a powertrain of a vehicle instead were to bedesigned as a propeller shaft, a much larger variety of the such measuring devices wouldhave to be provided in order to be able to provide corresponding torque measurements fromthe different vehicle models of the relevant manufacturer. 4 The measuring device for assessing a torque parameter of a vehicle may be utilised invarious kinds of motorised manned or unmanned vehicles, designed for land-basedpropulsion. However, in particular for heavy goods vehicles such as lorries, trucks, pickups,vans, wheel loaders, busses, and other heavy vehicles, assessment of a vehicle torqueparameter may be of particular relevance. Thus, it is particularly foreseen to use themeasuring device for assessing a torque parameter of a vehicle in heavy goods vehicles.

According to some embodiments the measuring device for assessing a torque parameter ofa vehicle comprises a sleeve connected to the first yoke and extending in parallel with atleast a portion of the axle at a radial distance from the axle, wherein the sleeve extends overthe torsion sensor. ln this manner the torsion sensor may be protected by the sleeve fromstone chipping and other external damage.

According to some embodiments, the torsion sensor comprises a strain gauge. ln thismanner a torque transferred via the measuring device may be easily measured. The straingauge provides a reading, which is directly proportional to transferred torque. Thus, aftercalibrating the measuring device, readings from the strain gauge may provide measurementsof the torque transferred via the measuring device. lt is further object of the present invention to provide a method for assessing a torqueparameter of a vehicle, which may be utilised in occasional precise torque assessment in avehicle.

According to a further aspect of the invention, the above mentioned object is achieved by amethod for assessing a torque parameter of a vehicle. The vehicle comprising at least onedrive wheel and a powertrain for driving the at least one drive wheel. The powertraincomprises a drive unit, a universal joint arrangement, and a propeller shaft. The universaljoint arrangement is connected to the propeller shaft via a slip joint. The method comprisessteps of: - demounting the universal joint arrangement from the powertrain, - replacing the universal joint arrangement with a measuring device for assessing a torqueparameter of a vehicle comprising a torsion sensor according to any aspect and/orembodiment discussed herein, - rotating the propeller shaft with the drive unit, - reading a measurement value from the torsion sensor, - determining the torque parameter based at least partially on the measurement value from the torsion sensor. 5 Since the method provides for replacement of a universal joint arrangement with a measuringdevice for assessing a torque parameter of a vehicle according to aspects and/orembodiments discussed herein, and determining the torque parameter of the vehicle basedat least partially on the measurement value from the torsion sensor of the measuring device,the above mentioned object is achieved.

Moreover, assessing a torque parameter under operation of the relevant vehicle duringrealistic operating conditions, i.e. in traffic and on roads with load, is made possible by thepresent method. Thus, the less than realistic operating conditions in a vehicle dynamometermay not be required for assessing a torque parameter.

The torque parameter may be a torque figure, but also figures calculated based on a torquefigure, such as e.g. a power figure, is herein encompassed by the term torque parameter.The torque parameter may be e.g. a momentary torque value, a mean torque value, a momentary power value, or a mean power value.

According to a further aspect of the invention there is provided a computer program forperforming a method for assessing a torque parameter of a vehicle, wherein the computerprogram comprises computer readable code configured to cause a central processing unit toperform a method according to any aspect and/or embodiment discussed herein.

According to a further aspect of the invention there is provided a computer program productfor performing a method for assessing a torque parameter of a vehicle, wherein the computerprogram comprises computer readable code configured to cause a central processing unit toperform a method according to any aspect and/or embodiment discussed herein.

Further features of, and advantages with, the present invention will become apparent whenstudying the appended claims and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS Various aspects of the invention, including its particular features and advantages, will bereadily understood from the example embodiments discussed in the following detaileddescription and the accompanying drawings, in which: Figs. 1A and 1B illustrate a measuring device for assessing a torque parameter of a vehicleaccording to embodiments, Fig. 2A schematically illustrates a vehicle comprising a powertrain, 6 Fig. 2B illustrates a measuring device for assessing a torque parameter of a vehicle and apropeller shaft, Fig. 3 illustrates a method for assessing a torque parameter of a vehicle, Fig. 4 illustrates a computer program product according to embodiments.

DETAILED DESCRIPTION Aspects of the present invention will now be described more fully. Like numbers refer to likeelements throughout. Well-known functions or constructions will not necessarily be describedin detail for brevity and/or clarity.

Figs. 1A and 1B illustrate a measuring device 2 for assessing a torque parameter of avehicle according to embodiments. Fig. 1A illustrates a partial cross section through themeasuring device 2 for assessing a torque parameter of a vehicle. The measuring device 2 isconfigured for use in a powertrain of a vehicle. More specifically, the measuring device 2 isdesigned as a universal joint arrangement. As such the measuring device 2 is configured toreplace an ordinary universal joint arrangement of a powertrain of a vehicle. Thus, themeasuring device 2 may be utilised for occasional precise torque assessment in thepowertrain of a vehicle.

The measuring device 2 for assessing a torque parameter of a vehicle comprises a first yoke4, a second yoke 6, and a universal joint cross 8. The first yoke 2 is connected to theuniversal joint cross 8 and the second yoke 6 is also connected to the universal point cross8. Thus, the first and second yokes 4, 6 are connected to each other via the universal jointcross 8. The first and second yokes 4, 6 comprise bearing seats for the universal joint cross8, which accordingly, is journalled in the first and second yokes 4, 6 to form a universal joint.The measuring device 2 further comprises an axle 10 having a first end portion 12 and asecond end portion 14. The first yoke 4 is connected to the first end portion 12 of the axle 10.The first yoke 4 being connected to the first end portion 12 of the axle 10 encompassesembodiments wherein the first yoke 4 and the axle 10 are formed from one piece, as well asembodiments wherein the first yoke 4 is attached to the axle 10. The axle 10 may be hollowas in the illustrated embodiments. Alternatively, the axle 10 may be solid. The second endportion 14 of the axle 10 is provided with splines 15 thus, forming part of a slip joint. The slipjoint being formed together with a corresponding mating part of a powertrain of a vehicle, e.g.a propeller shaft.

Also the second yoke 6 is configured for connection to the powertrain. The second yoke mayfor instance be connected to the powertrain via screws, threaded bolts and nuts, pins and 7 clips, or any other mechanical fastening arrangement which permits dismantling of thesecond yoke from the drive of a vehicle. ln these embodiments of the second yoke 6 isprovided with a four through holes 16 for connection to the powertrain. For instance, screwsor pins may extend through the four through holes 16 such that the second yoke 6 may betightened e.g. to an output end of a transmission of a drive unit of the vehicle. Alternatively,the second yoke 6 may be tightened to an end gear and/or a differential connected to at leastone drive wheel of the powertrain.

The measuring device 2 for assessing a torque parameter of a vehicle comprises a torsionsensor 18 arranged at the first end portion 12. ln these embodiments the torsion sensor 18comprise a strain gauge. The strain gauge is glued to the first end portion 12 of the axle at10. According to some embodiments, the strain gauge may comprise electrical conductorsarranged at a 45° angle to a longitudinal axis 20 of the axle 10. ln this manner the electricalconductors of the strain gauge extend are arranged on the axle 10, such that torsionalforces, i.e. torque, applied to the axle 10 extend or compress the electrical conductorsefficiently. For instance, a general purpose strain gauge having a shear/torque patternprovided by Micro - l\/leasurements TM, Vishay Precision Group TM may be utilised. Theelectrical conductors of the strain gauge may form a Wheatstone bridge or half a Wheatstonebridge.

A torsion sensor measures a torsion of the axle 10. A torsion of an axle is proportional to atorque applied to the axle. According to alternative embodiments, the torsion sensor 18 maybe of any suitable kind. For instance, the torsion sensor 18 may comprise a magneticallyencoded zone with a magnetic field that varies as a function of the torque that is transmittedthrough the axle 10, as discussed under the heading “Background” above. Further optionsmay be to utilise optical torsion sensors, or piezo-electrical sensors, as are known in the art.

The measuring device 2 for assessing a torque parameter of a vehicle comprises a sleeve 22connected to the first yoke 4. The sleeve 22 extends in parallel with at least a portion of theaxle 10 at a radial distance from the axle 10. The sleeve 22 extends over the torsion sensor18. ln this manner the torsion sensor may be protected from stone chipping and otherexternal damage by the sleeve.

According to some embodiments the measuring device 2 for assessing a torque parameterof a vehicle comprises a wireless transmitter 24. The torsion sensor 18 is connected to thewireless transmitter 24. ln this manner measurement values from the torsion sensor 18, or database on the measurement values, or the measurement values together with additional 8 data may be transmitted to a receiver. Thus, the measuring values may be utilised in furthercalculations and/or may be presented for evaluation.

According to alternative embodiments, measurement values from the torsion sensor 18 may be conducted to a receiver via slip rings arranged on e.g. the sleeve 22.

According to some embodiments, the wireless transmitter 24 is attached to the sleeve 22.Wires (not shown) may connect the torsion sensor 18 with the wireless transmitter 24. Thewireless transmitter 24 may comprise a processor for aggregation of measurement valuesfrom the torsion sensor 18, and/or other data. The transmitter 24 may for instance comprisea Wireless 2 Channel Analog lnput Sensor Node provided by LORD l\/licroStrain ® SensingSystems.

According to some embodiments, the measuring device 2 for assessing a torque parameterof a vehicle comprises a controller 26 configured to sample measurement values from thetorsion sensor 18. ln this manner the measuring device 2 may be configured to samplemeasurement values for continuous torque measurement with the measuring device 2 forassessing a torque parameter of a vehicle. The controller 26 may form one physical unittogether with the wireless transmitter 24. Alternatively, the controller 26 may comprise areceiver 25 and may be provided separate from the wireless transmitter 24, such as in an all-purpose computer, a dedicated processing device of the measuring device such as e.g. agateway of a LORD MicroStrain ® LXRS ® Wireless Sensor Network, or other suitabledevice. The controller 26 may be configured for processing, and/or evaluation, and/orpresentation of measurement values and/or data based on measurement values.Alternatively, the controller 26 may only provide partial processing of the measurementvalues, and/or sampling of the measurement values and send these to a device forevaluation, and/or presentation of the measurement values, and/or torque parameters basedon the measurement values, such as she a general purpose computer with a generalsoftware for data presentation or to a dedicated software for evaluation, calculation, and/orpresentation of torque parameters, such as the programme Node Commander ® provided byLORD MicroStrain ® Sensing Systems.

The wireless transmitter 24 may transmit for each measurement value a timestamp to thecontroller 26. Alternatively, the controller 26 may provide for each measurement value atimestamp. The timestamp may be utilised for presenting the measurement values, or torquevalues based on the measurement values, in a correct order, such as e.g. in a diagram or in a table. The timestamp may be utilised for correlating the measurement values, or torque 9 values based on the measurement values with further data, such as e.g. rotational speeddata of a drive unit of a relevant vehicle. The timestamp may be utilised for calculating furtherdata, such as developed power in a drive unit of the vehicle.

According to some embodiments, the splines 15 comprise ridges and grooves and thesecond end portion 14 has a bottom diameter, d2, at a bottom of the grooves. The first endportion 12, at the torsion sensor 18, has a smaller diameter, d1, than the bottom diameter,d2. ln this manner, the torsion sensor 18 may be arranged on the first end portion 12 notextending outside the bottom diameter, d2. Thus, a mating part of the slip joint of a relevantpropeller shaft may extend along the first end portion 12 without harming the torsion sensor18.

Mentioned purely as an example, for a heavy goods vehicle having a diesel engineproducing a torque within a range of 1500 - 3500 Nm, the measuring device may have abottom diameter, d2, of approximately 65 mm, the diameter, d1, at the torsion sensor may beapproximately 60 mm, and the axle 10 extending from the first yoke 4 may have a length ofapproximately 270 mm. The universal joint cross 8 may have a span of approximately 175 mm and a journaling diameter of approximately 55 mm. The sleeve may have a length ofapproximately 160 mm and a diameter of approximately 120 mm.

The measuring device 2 for assessing a torque parameter of a vehicle may be calibratedprior to being installed in a relevant vehicle. The measuring device 2 may be calibrated byfixing the second yoke 6 and subjecting the axle 10 to a number of known torque values. Foreach of the number of known torque values a reading from the torsion sensor 18 is taken.Accordingly, the readings from the torsion sensor 18 may be correlated with the knowntorque values. Since the torsion, twisting, of the axle 10 is proportional to the torque appliedto the measuring device 2, torque values in between the known torque values may beinterpolated. Thus, during use of the measuring device 2, measurement values from thetorsion sensor 18 may be correlated with the torque values transferred via the measuringdevice 2.

A measuring device comprising a torsion sensor comprising a strain gauge may alternativelybe calibrated in a known manner by means of shunt calibration utilising inter alia a shuntresistor and a gauge factor of the relevant strain gauge provided by a manufacturer of thestrain gauge. ln embodiments wherein the torsion sensor 18 comprises a strain gauge, a voltage applied tothe strain gauge will change proportionately to the torque applied to the measuring device 2.

Fig. 2A schematically illustrates a vehicle 30 comprising a powertrain 32. The powertrain 32comprises a measuring device 2 for assessing a torque parameter of a vehicle according to aspects and/or embodiments disclosed herein.

The vehicle comprising at least one drive wheel 34, more specifically in these embodiments,two drive wheels 34. The powertrain 32 is configured for driving the at least one drive wheel34. The powertrain comprises a drive unit 36, the measuring device 2 for assessing a torqueparameter of a vehicle, and a propeller shaft 38. The measuring device 2 for assessing atorque parameter of a vehicle is provided in the form of a universal joint arrangement. Duringordinary operation of the vehicle 30 an ordinary universal joint arrangement is comprised inthe powertrain 32. For measuring purposes, e.g. in order to measure a torque provided bythe drive unit 36, the ordinary universal joint arrangement has been replaced with the measuring device 2 for assessing a torque parameter of a vehicle.

Fig. 2B illustrates the measuring device 2 for assessing a torque parameter of a vehicle andthe propeller shaft 38 of Fig. 2A in more detail. The measuring device 2 and the propellershaft 38 are illustrated in a partial cross section. The measuring device 2 is connected to thepropeller shaft 38 via a slip joint 40. The slip joint 40 comprises external splines 15 on themeasuring device 2, as discussed above with reference to Figs. 1A and 1B, and matinginternal splines 39on the propeller shaft 38.

Returning to Fig. 2A, the drive unit 36 comprises a combustion engine 42 a clutch 44 and atransmission 46. The measuring device 2 is connected to an output shaft of the transmission46, as discussed above with reference to Figs. 1A and 1B. The powertrain 32 may furthercomprise and end gear 48 and two drive shafts 50. The end gear 48 may comprise adifferential. The propeller shaft 38 may be connected to the end gear 48 via a universal joint52. The end gear 48 is connected to the two drive shafts 50, each being connected to a drivewheel 34.

Mentioned purely as an example, in an implementation of the embodiments of Figs 2A and2B, wherein the measuring device 2 is connected to the transmission 46 by means of fourscrews extending through four through holes of a second yoke of the measuring device 2,replacing the ordinary universal joint arrangement with the measuring device 2 may beperformed in less than 10 minutes on a long-haulage tuck, without lifting the truck. The 11 replacement includes demounting the ordinary universal joint arrangement from thetransmission, lowering the propeller shaft together with the ordinary universal jointarrangement, sliding the ordinary universal joint arrangement from the propeller shaft, slidingthe measuring device onto the propeller shaft, and mounting the measuring device to the transmission.

The embodiments of Figs 2A and 2B illustrate one possible position of the measuring device2 in the powertrain 32. Alternative positions for the measuring device 2 may be at the endgear end of the propeller shaft 38, or at a support bearing between the transmission 46 andthe propeller shaft 38, or at a transfer gearbox, just to name a few. ln alternativeembodiments, the drive unit 36 may comprise an electric machine.

The combustion engine 42 may comprise the rotational speed sensor 54 for measuring arotational speed of the combustion engine 42 in a known manner. The rotational speedsensor 54 may for instance form part of an engine control system of the vehicle. Data fromthe rotational speed sensor 54 may be available via a diagnosis program. The rotationalspeed data may be utilised in calculation of a vehicle data together with the measurementvalues, or torque values based on the measurement values from the torsion sensor of themeasuring device 2 for assessing a torque parameter of a vehicle. The rotational speed datamay be timestamped in order to be correlated with the relevant measurement values fromthe torsion sensor, or for calculating torque parameters based on the measurement values and the rotational speed data.

Fig. 3 illustrates a method 100 for assessing a torque parameter of a vehicle. The vehiclemay be a vehicle 30 as discussed in connection with Figs 2A and 2B and comprises at leastone drive wheel and a powertrain for driving the at least one drive wheel. The powertraincomprises a drive unit, a universal joint arrangement, and a propeller shaft. The universaljoint arrangement is connected to the propeller shaft via a slip joint. The method 100comprises steps of: - demounting 102 the universal joint arrangement from the powertrain, - replacing 104 the universal joint arrangement with a measuring device comprising a torsionsensor according to any aspect and/or embodiment discussed herein, - rotating 106 the propeller shaft with the drive unit, - reading 108 a measurement value from the torsion sensor, - determining 110 the torque parameter based at least partially on the measurement value from the torsion sensor. 12 The measuring device has replaced the original universal joint arrangement of the vehicle. Atorque parameter related to the vehicle and affecting the torsion sensor thus, may be easily measured.

The step of determining 110 the torque parameter may be performed in a central processingunit, a processor, controller, or similar device. The measurement value from the measuringdevice is transferred to the central processing, processor, controller, or similar device. Basedon the measurement value, the central processing, processor, controller, or similar devicemay determine the torque parameter e.g. by comparing the measurement value with a look-up table to determine the torque parameter, or calculate the toque parameter using at leaston relevant formula and possibly a further input value or input values, such as a rotationalspeed of the measuring device or the drive unit, or correlating the measurement value with a relevant value of the torque parameter.

According to some embodiments, the method 100 for assessing a torque parameter of avehicle comprises steps of: - measuring 112 a rotational speed value of the drive unit or the propeller shaftsimultaneously with the step of reading 108 the measurement value from the torsion sensor,and wherein the step of determining 110 the torque parameter comprises a step of: - correlating 114 the torque parameter with the rotational speed value. ln this manner for a specific rotational speed a specific value of the torque parameter may becorrelated. This may for instance be utilised when presenting the torque parameter androtational speed value to a user, or when calculating the torque parameter when the torqueparameter comprises the rotational speed, such as e.g. in a power value.

According to some embodiments, the method 100 for assessing a torque parameter of avehicle comprises steps of: - repeating 116 the steps of: reading 108 a measurement value from the torsion sensor,measuring 112 a rotational speed value of the drive unit or the propeller shaft simultaneouslywith the measurement value from the torsion sensor, and determining 110 the torqueparameter, - correlating 118 at least some of the torque parameters thus determined with at least someof the rotational speed values, and - mapping 120 the torque parameters with their correlated rotational speed values. 13 ln this manner the torque parameters, e.g. torque values may be mapped againstcorresponding rotational speed values. The mapping 120 may for instance be presentedgraphically in a torque - rpm diagram, a torque -rpm table, a power- rpm diagram, or power-rpm diagram, on a display or a printed paper.

According to some embodiments, the method 100 for assessing a torque parameter of avehicle comprises steps of: - transmitting 122 wirelessly the measurement value or a determined torqueparameter from the torsion sensor to a receiver, and - logging 124 the measurement value from the torsion sensor or a determined torque parameter, in a memory. ln this manner the measurement value from the torsion sensor or the determined torqueparameter may be transferred to a computer memory. The measurement value or thedetermined torque parameter then is available for further processing thereof, such as theabove mentioned steps of determining 110, correlating 114, correlating 118, and/or mapping120.

According to some embodiments, the measurement value corresponds to a torque value transmitted from the drive unit via the measuring device to the at least one drive wheel.

The measurement value from the torsion sensor may directly correlate with a torque value asdiscussed above. Utilising relevant gear ratios, transmission losses, etc., a torque value ofthe drive unit, specifically a combustion engine thereof, may be assessed. Furthermore, apower value of the internal combustion engine may be calculated based on the torque value,T, and a rotational speed value, m, of the combustion engine, wherein the power, P = T * m.For instance, in this context the timestamp of the measurement value and the rotationalspeed value may be utilised. Alternatively, measurement values from the torsion sensor andthe rotational speed sensor of the combustion engine may be sampled simultaneously to ensure correlation therebetween.

According to some embodiments, the method 100 for assessing a torque parameter of avehicle comprises a step of: - calculating 126 a drive unit torque value based on the torque parameter.

Such a drive unit torque value may for instance be an output torque of a combustion engineof the drive unit. 14 Mentioned purely as an example, during performing the method 100 for assessing a torqueparameter of a vehicle, the relevant vehicle may be loaded close to its maximum loadingcapacity and driven along a steep uphill road section. Suitably, the vehicle speed may behigh at a beginning of the road section, but as the vehicle travels along the road section, thevehicle speed will gradually drop. During such operating conditions a full torque range, andpower range, of the drive unit of the vehicle may be evaluated.

Fig. 4 illustrates a computer program product 200 according to embodiments. The computerprogram product 200 is configured for performing a method for assessing a torque parameterof a vehicle, wherein the computer program comprises computer readable code configured tocause a central processing unit to perform a method according to any aspect and/orembodiment discussed herein. ln these embodiments the computer program product 200 comprises a CD-ROIVI disc.According to alternative embodiments the computer program product may comprise adifferent computer readable storage medium, such as a ROIVI, an EPROIVI, a CD ROIVI disc,a USB flash memory, etc. lt is to be understood that the foregoing is illustrative of various example embodiments andthat the invention is defined only by the appended claims. A person skilled in the art willrealize that the example embodiments may be modified, and that different features of theexample embodiments may be combined to create embodiments other than those describedherein, without departing from the scope of the present invention, as defined by theappended claims. For instance, more than one torque sensor may be arranged in themeasuring device. Such redundancy of sensors may provide a higher measuring accuracythan if only one torque sensor is used. According to some embodiments the measuringdevice 2 for assessing a torque parameter of a vehicle may be permanently mounted in avehicle. Thus, measurement values from the measuring device 2 for assessing a torqueparameter of a vehicle may be utilised in vehicle control during ordinary operation of thevehicle, such as e.g. in an engine control system, during gear change in an automated manual transmission, in a brake system, etc.

Claims (15)

1. A measuring device (2) for assessing a torque parameter of a vehicle comprising a firstyoke (4), a second yoke (6), a universal joint cross (8), and an axle (10) having a first endportion (12) and a second end portion (14), wherein the first and second yokes (4, 6) are connected to each other via the universaljoint cross (8), wherein the first yoke (4) is connected to the first end portion (12) of the axle (10),wherein the second end portion (14) of the axle (10) is provided with splines (15),wherein the second yoke (6) is configured for connection to a powertrain (32) of avehicle (30), and wherein the second end potion of the axle (10) forms part of a slip joint (40), characterised in that the measuring device (2) for assessing a torque parameter of a vehiclecomprises a torsion sensor (18) attached to the first end portion (12).

2. The measuring device (2) for assessing a torque parameter of a vehicle according to claim1, comprising a sleeve (22) connected to the first yoke (4) and extending in parallel with atleast a portion of the axle (10) at a radial distance from the axle (10), wherein the sleeve (22)extends over the torsion sensor (18).

3. The measuring device (2) for assessing a torque parameter of a vehicle according to claim1 or 2, comprising a wireless transmitter (24), wherein the torsion sensor (18) is connected tothe wireless transmitter (24).

4. The measuring device (2) for assessing a torque parameter of a vehicle according toclaims 2 and 3, wherein the wireless transmitter (24) is attached to the sleeve (22).

5. The measuring device (2) for assessing a torque parameter of a vehicle according to anyone of the preceding claims, wherein the splines (15) comprise ridges and grooves and thesecond end portion (14) has a bottom diameter (d2) at a bottom of the grooves, and whereinthe first end portion (12), at the torsion sensor (18), has a smaller diameter (d1) than thebottom diameter (d2). 16

6. The measuring device (2) for assessing a torque parameter of a vehicle according to anyone of the preceding claims, comprising a controller (26) configured to sample measurementvalues from the torsion sensor (18).

7. The measuring device (2) for assessing a torque parameter of a vehicle according to anyone of the preceding claims, wherein the torsion sensor (18) comprises a strain gauge.

8. A method (100) for assessing a torque parameter of a vehicle (30), the vehicle (30)comprising at least one drive wheel (34) and a powertrain (32) for driving the at least onedrive wheel (34), the powertrain (32) comprising a drive unit (36), a universal jointarrangement, and a propeller shaft (38), wherein the universal joint arrangement is connected to the propeller shaft (38) via a slipjoint (40), and wherein the method (100) comprises steps of: - demounting (102) the universal joint arrangement from the powertrain (32), - replacing (104) the universal joint arrangement with a measuring device (2) forassessing a torque parameter of a vehicle comprising a torsion sensor (18) according to anyone of the preceding claims, - rotating (106) the propeller shaft (38) with the drive unit (36), - reading (108) a measurement value from the torsion sensor (18), and - determining (110) the torque parameter based at least partially on the measurement value from the torsion sensor (18).

9. The method (100) for assessing a torque parameter of a vehicle (30) according to claim 8,comprising steps of: - measuring (112) a rotational speed value of the drive unit (36) or the propellershaft (38) simultaneously with the step of reading (108) the measurement value from thetorsion sensor (18), and wherein the step of determining (110) the torque parametercomprises a step of: - correlating (114) the torque parameter with the rotational speed value.

10. The method (100) for assessing a torque parameter of a vehicle (30) according to claims9, comprising steps of: - repeating (116) the steps of reading (108) a measurement value from thetorsion sensor (18), measuring (112) a rotational speed value of the drive unit (36) or the 17 propeller shaft (38) simultaneously with the measurement value from the torsion sensor (18),and determining (110) the torque parameter, - correlating (118) at least some of the torque parameters thus determined withat least some of the rotational speed values, and - mapping (120) the torque parameters with their correlated rotational speed values.

11. The method (100) for assessing a torque parameter of a vehicle (30) according to anyone of claims 8 - 10, comprising steps of: - transmitting wirelessly (122) the measurement value or a determined torqueparameter from the torsion sensor (18) to a receiver, and - logging (124) the measurement value from the torsion sensor (18) or a determined torque parameter, in a memory.

12. The method (100) for assessing a torque parameter of a vehicle (30) according to anyone of claim 8 - 11, wherein the measurement value corresponds to a torque valuetransmitted from the drive unit via the measuring device (2) for assessing a torque parameterof a vehicle to the at least one drive wheel (38).

13. The method (100) for assessing a torque parameter of a vehicle (30) according to anyone of claims 8 - 12, comprising a step of:- calculating (126) a drive unit torque value based on the torque parameter.

14. A computer program for performing a method (100) for assessing a torque parameter ofa vehicle (30), wherein the computer program comprises computer readable code configuredto cause a central processing unit to perform a method (100) according to any one of claims8 - 13.

15. A computer program product for performing a method (100) for assessing a torqueparameter of a vehicle (30), wherein the computer program comprises computer readablecode configured to cause a central processing unit to perform a method (100) according toany one of claims 8 - 13.