Method and system for determining a vehicle mass

• US 6,314,383 B1
• Filed: 07/06/1998
• Issued: 11/06/2001
• Est. Priority Date: 07/05/1997
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Hummel, Stefan, Leimbach, Klaus-Dieter, Veil, Hans
• Primary Examiner(s): Assouad, Patrick
• Assistant Examiner(s): Raymond, Edward
• Application Number:
  US09/110,810
• Time in Patent Office: 1,219 Days
• Field of Search: 702/173, 701/71, 701/79, 303/167, 177/25.11, 731/46, 738/65
• US Class Current: 702/173
• CPC Class Codes: B60T 2250/02 Vehicle mass
• CPC Class Codes: B60T 8/172 Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters B60T8/17551 takes precedence
• CPC Class Codes: B60W 2510/0657 Engine torque
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 40/076 Slope angle of the road
• CPC Class Codes: B60W 40/13 Load or weight
• CPC Class Codes: F16H 59/52 dependent on the weight of the machine, e.g. change in weight resulting from passengers boarding a bus
• CPC Class Codes: G01G 19/086 wherein the vehicle mass is dynamically estimated

Abstract

A method and a system for ascertaining a mass value representing the vehicle mass of a motor vehicle, particularly of a commercial vehicle, having a drive unit. An acquisition at least of a first and a second acceleration value is provided for this determination. These acceleration values represent the vehicle acceleration at a first and a second point of time. Further, at least one first and one second drive value are acquired. These drive values represent the drive force or the drive torque of the drive unit at the first and the second point of time. At least as a function of the acquired acceleration values and the acquired drive values, at least a first and a second driving-resistance value are then determined. The mass value is ascertained at least as a function of a comparison of the determined first driving-resistance or mass estimated value to the determined second driving-resistance or mass estimated value. A roadway slope is detected using the comparison, whereby an erroneous mass determination caused by the roadway slope is avoided.

Claims

1. A method for determining a vehicle mass value representing a vehicle mass of a motor vehicle having a drive unit, the method comprising the steps of:

(a) determining at least one first acceleration value indicative of a vehicle acceleration at a first time and at least one second acceleration value indicative of the vehicle acceleration at a second time;

(b) determining at least one first drive value and at least one second drive value, the at least one first drive value being indicative of one of a first drive force and a first drive torque of the drive unit at the first time, the at least one second drive value being indicative of one of a second drive force and a second drive torque of the drive unit at the second time;

(c) determining at least

a first ascertained value corresponding to at least one of a first driving resistance and a first mass estimated value, and

a second ascertained value corresponding to at least one of a second driving resistance and a second mass estimated value,

the first and second ascertained values being determined at least as a function of the at least one first and second acceleration values and the at least one first and second drive values;

(d) determining a roadway slope as a function of a difference between the first ascertained value and the second ascertained value; and

(e) comparing the roadway slope to at least one of the first ascertained value and the second ascertained value to determine the vehicle mass value.

3. The method according to claim 1, wherein step (e) includes the substep of:

(i) determining whether the first and second ascertained values are within a predetermined range.

4. The method according to claim 3, wherein the substep (i) includes determining whether at least one difference between the first and second ascertained values exceeds or drops below a predetermined threshold value.

5. The method according to claim 1, further comprising the step of:

(f) low-pass filtering the first and second ascertained values.

9. The method according to claim 1, wherein the motor vehicle is a commercial vehicle.

2. A method for determining a vehicle mass value representing a vehicle mass of a motor vehicle having a drive unit, the method comprising the steps of:

(a) determining at least one first acceleration value indicative of a vehicle acceleration at a first time and at least one second acceleration value indicative of the vehicle acceleration at a second time;

(b) determining at least one first drive value and at least one second drive value, the at least one first drive value being indicative of one of a first drive force and a first drive torque of the drive unit at the first time, the at least one second drive value being indicative of one of a second drive force and a second drive torque of the drive unit at the second time;

(c) determining at least

a first ascertained value corresponding to at least one of a first driving resistance and a first mass estimated value, and

a second ascertained value corresponding to at least one of a second driving resistance and a second mass estimated value,

the first and second ascertained values being determined at least as a function of the at least one first and second acceleration values and the at least one first and second drive values;

(d) comparing at least the first ascertained value with the second ascertained value to determine the vehicle mass value; and

(e) performing at least one of the following steps;

selecting the first and second times to vary one of the first and second drive values from another one of the first and second drive values in a predetermined manner,

wherein at least one difference between the first and second drive values exceeds or drops below a predetermined threshold value, and

generating a signal representing a gear ratio of a vehicle transmission,

wherein the first and second times are selected as a function of the generated signal, and

wherein varying transmission ratios are present at the first and second times.

6. A method for determining a vehicle mass value representing a vehicle mass of a motor vehicle having a drive unit, the method comprising the steps of:

(a) determining at least one first acceleration value indicative of a vehicle acceleration at a first time and at least one second acceleration value indicative of the vehicle acceleration at a second time;

(b) determining at least one first drive value and at least one second drive value, the at least one first drive value being indicative of one of a first drive force and a first drive torque of the drive unit at the first time, the at least one second drive value being indicative of one of a second drive force and a second drive torque of the drive unit at the second time;

(c) determining at least

a first ascertained value corresponding to at least one of a first driving resistance and a first mass estimated value, and

a second ascertained value corresponding to at least one of a second driving resistance and a second mass estimated value,

the first and second ascertained values being determined at least as a function of the at least one first and second acceleration values and the at least one first and second drive values; and

(d) comparing at least the first ascertained value with the second ascertained value to determine the vehicle mass value, the step (d) including the substep of;

(i) determining whether the first and second ascertained values are within a predetermined range,

wherein the vehicle mass value is determined only if the first and second ascertained values are within the predetermined range.

7. A method for determining a vehicle mass value representing a vehicle mass of a motor vehicle having a drive unit, the method comprising the steps of:

(a) determining at least one first acceleration value indicative of a vehicle acceleration at a first time and at least one second acceleration value indicative of the vehicle acceleration at a second time;

(b) determining at least one first drive value and at least one second drive value, the at least one first drive value being indicative of one of a first drive force and a first drive torque of the drive unit at the first time, the at least one second drive value being indicative of one of a second drive force and a second drive torque of the drive unit at the second time;

(c) determining at least

a first ascertained value corresponding to at least one of a first driving resistance and a first mass estimated value, and

a second ascertained value corresponding to at least one of a second driving resistance and a second mass estimated value,

the first and second ascertained values being determined at least as a function of the at least one first and second acceleration values and the at least one first and second drive values;

(d) comparing at least the first ascertained value with the second ascertained value to determine the vehicle mass value, wherein the vehicle mass value is determined as a function of at least one of the first and second ascertained values; and

(e) determining an average value as a function of the first and second ascertained values, the average value being the vehicle mass value.

8. A method for determining a vehicle mass value representing a vehicle mass of a motor vehicle having a drive unit, the method comprising the steps of:

(a) determining at least one first acceleration value indicative of a vehicle acceleration at a first time and at least one second acceleration value indicative of the vehicle acceleration at a second time;

(b) determining at least one first drive value and at least one second drive value, the at least one first drive value being indicative of one of a first drive force and a first drive torque of the drive unit at the first time, the at least one second drive value being indicative of one of a second drive force and a second drive torque of the drive unit at the second time;

(c) determining at least

a first ascertained value corresponding to at least one of a first driving resistance and a first mass estimated value, and

a second ascertained value corresponding to at least one of a second driving resistance and a second mass estimated value,

the first and second ascertained values being determined at least as a function of the at least one first and second acceleration values and the at least one first and second drive values;

(d) comparing at least the first ascertained value with the second ascertained value to determine the vehicle mass value, wherein the first and second ascertained values are determined as a function of at least one of a first further value representing a vehicle speed and a second further value representing a rotational speed of wheels of the motor vehicle.

10. A system for determining a vehicle mass value representing a vehicle mass of a motor vehicle having a drive unit, the system comprising:

a first determination arrangement determining at least one first acceleration value indicative of a vehicle acceleration at a first time and at least one second acceleration value indicative of the vehicle acceleration at a second time;

a second determination arrangement determining at least one first drive value and at least one second drive value, the at least one first drive value being indicative of one of a first drive force and a first drive torque of the drive unit at the first time, the at least one second drive value being indicative of one of a second drive force and a second drive torque of the drive unit at the second time;

a third determination arrangement determining at least

a first ascertained value corresponding to at least one of a first driving resistance and a first mass estimated value, and

a second ascertained value corresponding to at least one of a second driving resistance and a second mass estimated value;

a fourth determination arrangement determining a roadway slope as a function of a difference between the first ascertained value and the second ascertained value; and

a fifth determination arrangement determining the vehicle mass value by comparing the roadway slope to at least one of the first ascertained value and the second ascertained value.

14. The system according to claim 10, wherein the motor vehicle is a commercial vehicle.

11. A system for determining a vehicle mass value representing a vehicle mass of a motor vehicle having a drive unit, the system comprising:

a first determination arrangement determining at least one first acceleration value indicative of a vehicle acceleration at a first time and at least one second acceleration value indicative of the vehicle acceleration at a second time;

a second determination arrangement determining at least one first drive value and at least one second drive value, the at least one first drive value being indicative of one of a first drive force and a first drive torque of the drive unit at the first time, the at least one second drive value being indicative of one of a second drive force and a second drive torque of the drive unit at the second time;

a third determination arrangement determining at least

a first ascertained value corresponding to at least one of a first driving resistance and a first mass estimated value, and

a second ascertained value corresponding to at least one of a second driving resistance and a second mass estimated value; and

a fourth determination arrangement determining the vehicle mass value by comparing at least the first ascertained value with the second ascertained value

a further arrangement including at least one of;

an arrangement selecting the first and second times to vary one of the first and second drive values from another one of the first and second drive values in a predetermined manner,

wherein at least one difference between the first and second drive values exceeds or drops below a predetermined threshold value, and

an arrangement generating a signal representing a gear ratio of a vehicle transmission,

wherein the first and second times are selected as a function of the generated signal, and

wherein varying transmission ratios are present at the first and second times.

12. A system for determining a vehicle mass value representing a vehicle mass of a motor vehicle having a drive unit, the system comprising:

a first determination arrangement determining at least one first acceleration value indicative of a vehicle acceleration at a first time and at least one second acceleration value indicative of the vehicle acceleration at a second time;

a second determination arrangement determining at least one first drive value and at least one second drive value, the at least one first drive value being indicative of one of a first drive force and a first drive torque of the drive unit at the first time, the at least one second drive value being indicative of one of a second drive force and a second drive torque of the drive unit at the second time;

a third determination arrangement determining at least

a first ascertained value corresponding to at least one of a first driving resistance and a first mass estimated value, and

a second ascertained value corresponding to at least one of a second driving resistance and a second mass estimated value; and

a fourth determination arrangement determining the vehicle mass value by comparing at least the first ascertained value with the second ascertained value, the fourth determination arrangement determining whether the first and second ascertained values are within a predetermined range.

13. The system according to claim 12, wherein the fourth determination arrangement determines whether at least one difference between the first and second ascertained values exceeds or drops below a predetermined threshold value.