SE526514C2 - Motor vehicle with transmission - Google Patents

Abstract

The invention relates to an engine-driven vehicle comprising at least one engine (10), and control elements (45; 48) designed to control a transmission (90) that can be driven by the engine, the control elements being designed to receive a first signal transmitted from a first sensor (115) and containing information on the gradient of the vehicle running surface, and to receive a second signal transmitted from a second sensor (110; 113) and containing information on the torque, and to receive a third signal transmitted from a third sensor (114) and containing information on the vehicle acceleration, in which the control elements are further designed to calculate the mass (m(i); m ) as a function of the first, second and third signals, and to control the transmission as a function of the vehicle mass calculated.

Description

526 514 2 Another view of the invention is to obtain a better basis for controlling the transmission in a cost-effective manner.

The above objects are achieved with a motor-driven vehicle comprising at least one motor, control means arranged for controlling a motor-drivable transmission, the control means being arranged to receive a first signal transmitted from a first sensor which includes information about the inclination of the vehicle base, and to receive a second signal transmitted from a second sensor comprising information on torque, and receiving a third signal transmitted from a third sensor comprising information on the acceleration of the vehicle, the control means further being arranged to calculate the mass of the vehicle in dependence on the first, second and third signals , and to control the transmission depending on the calculated vehicle mass.

In this way, incorrect changes during driving of the vehicle are avoided.

By using significant components already in the vehicle, according to the invention a more correct information is obtained which is used as a decision basis for controlling the transmission in a cost-effective manner.

Preferably, said calculation takes place in dependence on a predetermined information which includes a rolling resistance constant, lu fi resistance constant, gravity acceleration, gear ratio in the rear axle of the vehicle, gear ratio in the vehicle gearbox and the efficiency of the vehicle driveline and wheel radius. This gives the advantage of obtaining a good and correct estimate of the mass of the vehicle in a fast and correct manner, since these values are already available to be taken into account in the calculation of the mass of the vehicle. In this way, an improved accuracy of information is also obtained which is to be used as a decision basis for controlling the transmission.

Preferably, the mass of the vehicle is also calculated depending on the speed of the vehicle. 10 15 20 25 30 5 2 6 5 1 4 3 According to the invention, the vehicle obtains better performance during propulsion because control of the transmission is based on more accurate information. The vehicle can thus e.g. performed in a more fuel-efficient way.

An additional advantage of the invention is that an upshift to a gear that provides insufficient driving force is avoided. Another advantage is that the invention is well suited both for automatic as well as for automated gearboxes, ie both with and without collar interruptions during, for example, acceleration. General description of the drawings Figure 1 shows a schematic representation of a motor vehicle and a control system for the same.

Figure 2 shows a line with examples of detected or calculated data, among which some are used according to the invention.

Figure 3a shows schematically how the inclination of a base for a vehicle is defined according to an embodiment of the invention.

Figure 3b shows schematically how the inclination of a base for a vehicle is defined according to a form of erosion of the invention.

Figure 3c shows a table of measured and calculated data used according to an embodiment of the invention.

Figure 4a shows a fate diagram illustrating a method according to the invention.

Figure 4b shows a fate diagram illustrating a method for calculating vehicle mass according to an embodiment of the invention.

Figure 4c shows a fate diagram illustrating a method for calculating vehicle mass according to an embodiment of the invention. Figure 4d shows a fate diagram illustrating a method for calculating vehicle mass according to an embodiment of the invention.

Figure 4e shows a fate diagram illustrating a method for controlling the transmission of the vehicle according to an embodiment of the invention.

Figure 5 schematically shows a computer device used according to an embodiment of the invention.

Detailed Description of the Drawings Figure 1 shows a schematic representation of a vehicle 1 and a control system therefor according to an embodiment of the present invention where 10 denotes an engine, e.g. a six-cylinder diesel engine, the crankshaft 20 of which is coupled to a single-disc dry single-clutch coupling generally designated 30, which is enclosed in a clutch housing 40. Instead of a single-disc disc clutch, a two-disc clutch can be used. The crankshaft 20 is non-rotatably connected to the coupling housing 50 of the clutch 30, while its manifold 60 is non-rotatably connected to an input shaft 70, which is rotatably mounted in the housing 80 of a gearbox generally designated 90. In the housing 80, a main shaft and an intermediate shaft are rotatably mounted. A shaft 85 extending from the gearbox 90 is arranged to drive the wheels of the vehicle.

Furthermore, a first control unit 48 for controlling the motor 10 and a second control unit 45 for controlling the transmission 90 are illustrated. The first and second control units are adapted for communication with each other via a line 21. In the latter it is described that different processes and method steps take place in the second control unit 45, but it should be understood that the invention is not limited thereto but that the first control unit 48 may be used as well, or a combination of the first and second control units. The second control unit 45 is arranged for communication with the transmission 90 via a line 24. The first control unit 48 is arranged for communication with the motor 10 via a line 26. The first and second control units can generally be referred to as control means. The vehicle 1 has a throttle control 44 and a manual gear selector 46, which are adapted for communication with the second control unit 45 via a line 210 and 211, respectively.

The gear selector 46 may have a position for manual shifting and a position for automatic shifting of the vehicle. The accelerator control can be an accelerator pedal. A sensor 113 is arranged to continuously measure the position of the throttle control. The sensor 113 is arranged for communication with the second control unit 45 via a line 212. The position of the throttle control implicitly indicates the amount of fuel supplied to the combustion chamber of the engine. The amount of fuel added indicates engine torque. The second control unit 45 can thus continuously calculate a value representing motor torque based on a signal sent from the sensor 113.

Detector means 11 1 are arranged to detect, measure, estimate or register various conditions of e.g. the motor 10. The detector means can be of different types. Examples of. detector means are motor torque sensor llla and motor rectifier sensor 1 1 lb. Figure 1 shows only detector means generally denoted by 11 1. The detector means 111 are arranged for communication with the first control unit 48 with a line 28.

Furthermore, there is an acceleration sensor 114 arranged to detect the acceleration a of the vehicle a. The acceleration sensor 114 is arranged to continuously detect instantaneous vehicle acceleration a (i) and communicate these values to the first control unit 48 via a line 215. In the first control unit 48 a detected acceleration value a together with a time stamp R (i). The designation a (i) means measured acceleration at time (i), which time is indicated by the time stamp R (i). The timestamps R (i) are generated by the first control unit 48. Alternatively, measured acceleration a is provided with a corresponding time stamp R (i) in the acceleration sensor 114, after which the acceleration value with time stamp a (i) is sent to the first control unit 48.

According to one embodiment, the acceleration sensor 114 is arranged to continuously send signals representing vehicle acceleration to the second control unit 45 via the first control unit 48.

A torque sensor 110 is, according to one embodiment, arranged to measure the torque of the input shaft 70. The torque sensor 110 is arranged to measure the torque provided by the motor 10 at the input shaft 70. The torque sensor 110 is arranged for communication with the second control unit 45 via a line 22. The torque sensor 110 is arranged to continuously communicate a instantaneous value representing the input shaft torque to the second control unit 45. The communicated value representing the input shaft torque can be communicated in the form of an electrical signal to the second control unit. The signal may alternatively be an optical signal. The signal can be analog or digital. The second control unit is arranged to convert the received signal in a suitable manner, e.g. by means of an A / D converter (not shown in fi gur).

The torque sensor 110 may be arranged to measure the torque of the output shaft 85.

The torque sensor 110 is here arranged to measure the torque produced by the motor 10 at the output shaft 85. It should be seen that the torque sensor arranged in this way is arranged to measure torque within a larger torque range than in the case of measuring the torque of the input shaft.

The torque sensor 1 10, when placed on the input shaft 70, can be easily used for other applications, such as e.g. clutch control. Data received by the torque sensor is registered in the second control unit 45. Received data registered by the second control unit 45 is stored in a memory. Data measured by the torque sensor and later stored in the memory in the second control unit 45 are according to one embodiment torque with associated timestamps. According to one embodiment, instantaneous nominal values T (i) are measured every 100 milliseconds (0, ls) and the respective estimated value is stored with an associated time stamp R (i). The timestamps R (i) are generated by the second control unit 45, therein is an integer between 1 and N. N is an integer, e.g. 1000. Table 1 below shows an example of four initial measurements for the transmission's first and lowest gear in vehicle acceleration, e.g. during acceleration or engine braking. Corresponding measurements can be performed for all of the transmission gears and stored in dedicated tables in the second control unit 45. (i) T (i) [Nm] R (i) lsl 1 0 0.100 2 100 0.200 3 200 0.300 4 300 0.400 10 15 20 25 30 526 514 7 Table 1, Measured torque T (i) with respective time stamps R (i).

According to one embodiment, the torque sensor 1 is arranged to continuously transmit signals representing torque to the second control unit 45.

Since the gear ratio and efficiency of the transmission are known, the engine torque of the output shaft 85 can be continuously calculated. Since the torques of the output shaft are different for different engaged gears, this is taken into account in the calculations. According to one embodiment, data representing calculated values for the torque of the output shaft 85 are stored together with associated timestamps in the memory of the second control unit 45.

The engine torque can be calculated based on the amount of fuel injected into the engine's combustion chamber. Account is also taken of any additives that may be used to obtain good estimates of torques. The calculation can be done in the second control unit 45.

An inclination sensor 115 is pre-arranged at the gearbox 90. According to one embodiment, the inclination sensor 1 is pre-arranged in the gearbox 90. The inclination sensor 115 is arranged to measure the inclination of the ground on which the vehicle 1 is located. Sometimes the ground is a road whose slope is measured. The tilt sensor 11 may be of a piezoelectric type.

The inclination sensor 115 is arranged for communication with the second control unit 45 via a line 23. According to one embodiment, the inclination sensor 115 is arranged for continuously transmitting signals representing the inclination of the substrate to the second control unit 45.

According to another embodiment, signals representing the inclination of the substrate are transmitted to the second control unit at certain intervals, e.g. 0.01 second interval or 0.5 sect interval.

According to one embodiment, signals representing the ground slope, engine torque, vehicle acceleration and vehicle speed are continuously transmitted to the second control unit 45 where they are stored in an array along with the respective time stamp. 10 15 20 526 514 s The arrangement is stored in the second control unit 45. The arrangement is also referred to as the table. Figure 3c below describes such a table.

According to one embodiment, values S (i) representing the slope of the substrate are measured by the slope sensor 115 every 10 milliseconds (0.1s) and the respective measured value is stored with a respective corresponding time stamp R (i). The timestamps R (i) are generated by the second control unit 45, where i is an integer. Table 2 below shows an example of four initial measurements for the transmission's first and lowest gears. Corresponding measurements can be performed for all of the transmission gears and stored in dedicated folders in the second control unit. It should be noted that the timestamps are the same as described above, with reference to Table 1. Thus, S (1), T (1) and a (i) are measured substantially simultaneously and form a first data group (i = 1) measured e fi er 0 , 1 second (R (1)). S (2), T (2) and a (i) are measured substantially simultaneously and form a second data group (i = 2) measured after 0.2 seconds (R (2)). Table 2 does not explicitly state the respective measured slopes. (i) S (i) [rad] R (i) [S] 1 s (1) 0.1 2 s (2) 0.2 3 so) 0.3 4 s (4) 0.4 Table 2, Measured slope of the vehicle's base S (i) with the respective time stamp R (i).

In the same way as for the moment T (i) and the slope of the vehicle's base S (i), the vehicle's acceleration is measured and registered by the acceleration sensor 114 and provided with corresponding time star plates R (i). The vehicle's acceleration is stored in a table 3 as below. (i) a (i) [rad] R (i) [S] 1 a (i) 0.1 2 a (2) 0.2 3 aa) 0.3 4 a (4) 0.4 10 15 20 526 514 9 Table 3, Measured vehicle acceleration a (i) with respective time stamp R (i).

Similarly, a speed sensor 116 arranged for communication with the first control unit 48 via a line 216 detects the speed of the vehicle and communicates this value in the form of a signal. The vehicle speed is stored in a table 4 as follows: (i) V (i) [row] R (i) lsl 1 v (1) 0.1 zv (2) 0.2 3 v (3) 0.3 4 v (4) 0.4 Table 4, Measured vehicle speed V (i) with respective time stamp R (i).

According to one embodiment, the vehicle's acceleration is calculated based on the vehicle's speed.

This thus enables the use of only one sensor instead of two to obtain the acceleration and speed of the vehicle, respectively.

It is generally known that FD -FR = ma (1) where, F D is the total driving force of the vehicle which according to an embodiment of the invention is estimated according to equation 2 below. TUßf, FD R (2) Furthermore, FR is the total resistance which according to an embodiment of the invention is estimated according to equation 3 below.

FR = mgsin (a) + k, m + k2V2 (3) 10 15 20 25 526 514 10 where, kl is a rolling resistance constant; kz is a luminosity constant; g is the acceleration of gravity; V is the speed of the vehicle; B is the gear ratio in the rear axle of the vehicle; U is the gearbox in the vehicle gearbox; T is engine torque; a is the slope of the vehicle's surface; 17 is the efficiency of the vehicle's driveline; and R is wheel radius.

An alternative designation for a is S. S (i) is thus a designation for a a which is related to a certain time stamp R (i). (1) + (2) + (3) ger T UB.

-Tïl- (mg s1n (a) + k, m + kzVz) = ma (4) At least two cases become clear: Case 1.

Assume that the speed of the vehicle is pollutable, i.e. V z 0, or that V is less than a certain given limit value, e.g. Skm / h, and thus assigned a value equal to zero, then an estimate of the vehicle mass m is given with equation 5 below: TUBI; »W-f-R- (S) g s1n (a) + k] + a 10 15 20 25 526 514 11 Case 2 Assume that the speed of the vehicle is not pollutable, i.e. V: k 0, or at least higher than a certain given limit value, e.g. Skm / h, then an estimate of the vehicle mass m is given with equation 6 below: room; _ k V, R 2 m ---_-_ (e) _ gsin (a) + k1 + a It should be clear that the values of e.g. k,, k,, B and 17 may vary while driving but are not further described in the present description. One or fl era of k,, k,, g, B, U and 17 may be stored in the other control unit as constants to be used in calculations of the vehicle mass m as above. According to one embodiment, there is a set of values for each pair of networks. There can be five different values for the air resistance constant k,, for example depending on whether a trailer is connected to the vehicle 1 or not. Furthermore, it can e.g. there can be five different values for the gravitational acceleration gl-gg, among which a best value, e.g. gg, can be selected for use in mass calculations. Alternatively, one or more of k,, k,, g, B, U and 17 may be detected and fed to the second control unit 45 for use in vehicle mass calculations m as above. Efficiency in vehicle driveline 1; may vary while driving the vehicle. The efficiency can e.g. vary between 0.97 and 0.99. The efficiency is typically different for different gears. The wheel radius is typically a constant that is stored in the second control unit 45.

The equation (5) can also, according to an embodiment of the present invention, be expressed as: T (i) UB17 - = R mm gsin (s (i)) + k, + a (i) (7) The equation (6) can also, according to an embodiment of the present invention, are expressed: 10 15 20 25 30 526 514 12 - _ R mm "gsilrsnu) + k, + an) (8) Figure 2 shows line 28 and examples of travel data detected, measured, estimated or recorded by The detector means 11 1. Examples of travel data are, for example, engine torque 201, crankshaft torque 202, engine power 203, external wind conditions 204, exhaust back pressure 205 and fuel consumption 206.

Other travel data used are vehicle speed V, gear ratio U, road clearance a and efficiency of driveline 11. According to the invention, gravity acceleration g, rolling resistance constant k] and air resistance constant k are also used to calculate vehicle mass as above.

In Figure 3a, a dashed line B illustrates a cross section of a horizontal plane. A solid line A illustrates a cross-section of a flat surface having an inclination of radians relative to the horizontal plane B. The solid line A may typically represent a cross-section of a flat road on which the vehicle 1 is driven. Figures 3a and 3b assume that the direction of travel of the vehicle is from left to right. The flat surface A in 3 gur 3a is thus an uphill slope ßr the vehicle.

In Figure 3b, a dashed line B similarly illustrates a cross section of a horizontal plane. A solid line A illustrates a cross section of a flat surface which has a slope of radians relative to the horizontal plane B. Under the same assumption as in Figure 3a, the flat surface is thus a downhill slope for the vehicle. It should be clear that the slope a here is minus (-) a radians relative to the horizontal plane B.

With reference to Figure 3c, a table G1 with entered data is illustrated according to an embodiment of the invention.

The table shown in Figure 3c includes measured and calculated values for a first gear G1. corresponding tables are available according to an embodiment of the inventory for all the gears of the vehicle. Thus, according to an embodiment, where the transmission has 12 different gears, there is a table for each of the transmission's 12 gears. Data is stored in the various tables and CD 526 514 13 takes place as described above. The different tables are named G1 to G12 for each gear.

The table illustrated in Fig. 3c contains N rows. N is an integer. N can e.g. be equal to 50.

Instantly detected values T (i), a (i), S (i) and V (i) ns nns are stored in the table of the measured data values for the vehicle's first gear. For each set of data values (same (i)), a respective value m (i) representing either the vehicle mass calculated by Equation 7 or 8 is calculated depending on the speed V of the vehicle.

It should be noted that your tables G1 can be found, as well as your tables G2 and so on. Each time an estimate of the vehicle mass according to the present invention is performed, a new table can be created for a given gear ratio on the vehicle's driveline.

According to one embodiment, a table contains a series of measurements. According to another embodiment, a table innehåller contains your measurement series. Measurement series refers to measured values measured and calculated in a sequence for a determined gear ratio for a substantially constant actual vehicle mass M.

The calculated vehicle masses m (1) -m (N) should have a relatively small standard deviation, provided that they relate to the same measurement series.

Below are two examples that illustrate how the vehicle mass can be calculated.

Exernæl l According to this example, m (i), m (2) and m (3) illustrated in Fig. 3c are used. I.e. the first three calculated vehicle masses for the lowest gear of the transmission are used, An average value ñ is calculated in the second control unit 45, where 3 m = 2m (i) / 3 (9) i = 1 Example 2 10 15 20 25 30 5 2 6 5 1 4 According to this example, the first three calculated vehicle masses for the lowest gear of the transmission (from Table G1) and three sequential calculated values for the second gear of the vehicle, namely m (7), m (8) and m (9) stored in the table are used G2.

An average value ñ is calculated in the second control unit 45, where [GHÉ m (i) + [GÄÉ m (i) i = l 6 i = 7 ïñ: According to this example, parts of measurement series are used for different gears (different tables G1 - G1 2 ) to calculate an average value ñ for the estimate of the actual vehicle mass M. It should be noted that the actual vehicle mass M is substantially the same for the two subseries.

Figure 4a shows a flow chart illustrating a method for calculating the mass of a motor vehicle according to an embodiment of the invention. According to a first method step s401, the sub-steps are performed to: - receive a first signal comprising information about the inclination of the vehicle base; - receiving a second signal including information about torque; - receiving a third signal including information about the acceleration of the vehicle; and - calculating the mass of the vehicle depending on the first, second and third signals; and to - control the vehicle's transmission depending on the calculated vehicle mass.

According to an embodiment of the invention, the mass of the vehicle is calculated before a first shift after starting.

According to one embodiment, a fourth signal is received comprising information on the speed of the vehicle and in calculating the mass of the vehicle using the signal, Figure 4b shows a flow chart illustrating a method for calculating vehicle mass. according to an embodiment of the invention. According to a first method step s404, the gear ratio present in the vehicle transmission is detected.

In a subsequent method step s406, it is determined whether a table already exists for the detected gear. If so, then Yes, follow a method step s450 with reference to Figure 4c. If there is no already created table, ie No, a method step s408 follows.

In method step 408, a table is created for storing measured data, such as detected torque T (i) and the inclination of the ground S (i), vehicle acceleration a (i) and the vehicle speed V (i). The table is intended to store measured or processed data with respect to a specific gear ratio of the vehicle's driveline, i.e. the gear detected in method step s404. The detected gear ratio in this example is the lowest gearbox of the gearbox, also called a first gearbox. A created table is according to this example the one shown with reference to Figure 3c, i.e. Gl. The table is created and stored in a memory in the second control unit 45. The table (6xN, where N = 10) is empty after it has been created. The table is dynamic, i.e. Your rows can be created without your measured data being stored. Additional rows in the table can be created automatically by the other control unit as received data is registered.

In a method step s412, a value for measured torque T (i) is registered, as a representation of the motor torque. Furthermore, the vehicle's acceleration a (i), the slope of the ground, which in this case is the road inclination a, denoted S (i) and the vehicle's speed V (i) are recorded. Registered values according to this method step have the same time stamp R (i). If e.g. R (i) is R (1), T (1), a (1) and so on are stored. on a row in the table. After method step s412, method step s41 6 follows.

In method step s416 the variables and constants are received which, in addition to the data recorded according to the previous method step s412, are included in the calculation of the mass of the vehicle with reference to equation 7 or 8, i.e. k ,, k,, g, B, U, R and 17. The method step 416 is followed by a method step s418. In method step s418, the vehicle mass m (i) is calculated according to Equation 7 or 8 using T (i), S (i), a (i) and V (i), respectively, and adequate values of k ,, k,, g, B, U, R and 17.

According to one embodiment, both the vehicle mass are calculated according to Equation 7 and 8. Method step s41 8 is followed by a method step s420.

In method step s420, the result m (i) of the calculation performed in s41 8 is stored in a memory in the second control unit 45. Method step s420 is followed by a method step s424.

In the method step s424 a decision is made whether a above procedure should be repeated, i.e. whether a new row containing new T (i), S (i), a (i) and V (i) for a subsequent time (i + 1) should be entered in the table. If this is the case, then Yes, the method step s4l2 follows. If this is not the case, then No, the method ends. A program stored in the second control unit 45 controls the decision-making according to certain criteria.

Furthermore, a decision is made as to whether stored information should be deleted from the table. If so, the information will be deleted.

Figure 4c shows a fate diagram illustrating a method for calculating vehicle mass according to an embodiment of the invention. According to method step s450, an already created table is selected that corresponds to the current gear ratio on the vehicle's driveline. The selected table can e.g. be Gl which corresponds to the lowest gear of the vehicle, i.e. the first gear of the vehicle. Method step s450 is followed by a method step s453.

In method step s453, T (i), S (i), a (i) and V (i) are received. Method step s453 is followed by a method step s456.

In method step s456, k,, k,, g,, U, R and n are received. Method step s456 is followed by a method step s457.

In method step s457, the vehicle mass m (i) is calculated according to Equation 7 or 8 using data received in s453 and s456. Method step s457 is followed by a method step s459. In the method step s459, the result m (i) from the method step s457 is stored in a memory in the second control unit 45. The method step S459 is followed by a method step s462.

In method step s462, a decision is made whether to repeat the above procedure, i.e. whether a new row containing new T (i), S (i), a (i) and V (i) for an e fi following time (i + 1) should be entered in the table. If this is the case, then Yes, the method step s450 follows. If this is not the case, then No, the method ends. A program stored in the second control unit 45 controls the decision-making according to certain criteria.

Figure 4d shows a fate diagram illustrating a method for calculating vehicle mass according to an embodiment of the invention.

In method step s480, one or more of your tables G1-G12 are selected. Method step s480 is followed by a method step s483.

In method step s483, a number of calculated vehicle masses m (i) are selected from the respective selected tables G1-G12. The selected vehicle masses are all calculated under essentially the same load conditions, i.e. the actual vehicle mass M is essentially the same. However, the different calculated vehicle masses m (i) can thus be calculated for different gears in the vehicle's driveline and thus be stored in different tables. Method step s483 is followed by a method step s485.

In method step s485, the average value of the selected calculated vehicle masses is calculated to obtain a good approximation ü of the actual vehicle mass M. Method step s485 is followed by a method step s488.

In the method step s488, ñ is stored in the second control unit in order to be able to be used as a basis for a gear selection strategy stored therein. After the method step s488, the method ends.

Figure 4e shows a fate diagram illustrating a method for controlling the transmission of the vehicle according to an embodiment of the invention where the method steps S486 through s485 are the same as described with reference to Figure 4d. Method step s485 is followed by a method step s499. 10 15 20 25 30 526 514 1s In method step s499, the transmission of the vehicle is controlled depending on the calculated value ñ representing the actual mass M of the vehicle without first having been stored in a table. This is to implement in a even faster way a good estimate of the vehicle mass as control information. One method step s499 terminates the method.

Figure 5 shows an apparatus 500, according to an aspect of the invention, comprising a useless memory 520, a data processing unit 510 comprising a processor, and a read and write memory 560. The memory 520 has a first memory portion 530, in which a computer program controls. of the device 500 is stored. The computer program in the memory portion 530 for controlling the apparatus 500 may be an operating system.

The device 500 may be enclosed in e.g. a control unit, such as the control unit 45 or 48.

According to a preferred embodiment, an apparatus 500 is internally incorporated in both the first and second control units 45 and 48. The data processing unit 510 may comprise e.g. a microcomputer.

The memory 520 also has a second memory portion 540, in which programs including methods with reference to Figures 4a-4e are stored. In an alternative embodiment, the program is stored in a separate non-volatile data storage medium 550, such as, for example, a CD or a replaceable semiconductor memory. The program can be stored in an executable form or in a compressed state.

Since it is described in the following spirit that the data processing unit 510 runs a special function, it should be clear that the data processing unit 510 runs a special part of the program, which is stored in the memory 540 or a special part of the program, which is stored in the non-volatile recording medium 550.

The data processing unit 510 is adapted for communication with the memory 550 via a data bus 514. The data processing unit 510 is also adapted for communication with the memory 520 via a data bus 512. Furthermore, the data processing unit 510 is adapted for communication with the memory 560 via a data bus 51 1 The data processing unit 510 is also adapted for communication with a data port 590 via a data bus 515. The methods described in Figures 4a-e can be performed by the data processing unit 510 by the data processing unit 510 running the program, which is stored in the memory 540 or program, which is stored in the non-insp recording medium 550.

In the second memory part 540, a computer program comprising program code for storing the method steps according to the fl desires heman is stored, with reference to one of the guras 4a-e, when said computer program is executed on a computer.

For use in the invention, a computer program product comprising program code is stored on a computer readable medium for performing the method steps according to fate diagrams, with reference to any of Figures 4a-e, when said computer program is executed on the computer.

For use in the invention, a computer program product is found directly loadable into an internal memory of a computer, including computer programs for performing the method steps according to fate diagrams, with reference to any of Figures 4a-e, when said computer program product is executed on the computer.

Claims (10)

10 15 20 25 30 526 514 zo Patentkrav A motor vehicle comprising at least one motor (10), control means (45; 48) arranged to control a motor-drivable transmission (90), the control means being arranged to receive a first signal transmitted from a first sensor (115) comprising information on the inclination of the vehicle surface, and to receive a second signal transmitting from a second sensor (1 10; 113) which includes information on torque, and to receive a third signal transmitted from a third sensor (1 14) which includes information on vehicle acceleration; characterized in that the control means are further arranged to calculate the mass (m (i); ñ) of the vehicle in dependence on the first, second and third signals, and to control the transmission in dependence on the calculated vehicle mass. Motor-driven vehicle according to Claim 1, characterized in that the second sensor is a torque sensor (110) which is arranged to measure the torque of a shaft included in the transmission and / or a torque and / or motor torque of the shaft output from the transmission. Motor vehicle according to claim 1, characterized in that the second sensor is a sensor (113) which is arranged to measure the throttle control position and thus information on a quantity of fuel supplied to the engine representing engine torque. Motor vehicle according to one of Claims 1 to 3, characterized in that the calculation of the mass of the vehicle also takes place in dependence on the speed of the vehicle. A method for calculating the mass of a motor vehicle, the method comprising the steps of: - receiving a first signal comprising information about the inclination of the vehicle's surface; - receive a second signal including information about torque; - receiving a third signal including information about the acceleration of the vehicle; characterized by the steps of - calculating the mass of the vehicle in dependence on the first, second and third signals; and controlling the transmission of the vehicle depending on the calculated vehicle mass. Method according to claim 5, further characterized by the step of calculating the mass of the vehicle in dependence on the second signal comprising information about the torque of an axle included in the vehicle transmission and / or a torque of the shaft output to the vehicle transmission and / or the vehicle engine torque. A method according to claim 5, further characterized by the step of calculating the mass of the vehicle in dependence on the second signal comprising information on an amount of fuel supplied to the engine representing engine torque. Method according to one of Claims 5 to 7, characterized in that - calculates the mass of the vehicle before a first change or start. Method according to one of Claims 5 to 8, further characterized by the step of - receiving a fourth signal comprising information on the speed of the vehicle and calculating the mass of the vehicle in dependence on the fourth signal. A computer program product comprising program code for performing the method steps of claim 5, when said computer program is executed on a computer. A computer program product comprising program code stored on a computer readable medium for performing the method steps of claim 5, when said computer program is executed on the computer.