Method and system for ascertaining the emergency running condition of a pneumatic tire

• US 6,591,668 B1
• Filed: 02/28/2000
• Issued: 07/15/2003
• Est. Priority Date: 02/26/1999
• Status: Expired due to Fees

• Current Assignee: Continental Reifen Deutschland GmbH (Continental AG)
• Original Assignee: Continental AG, Continental Teves AG & Co. OHG (Continental AG)
• Inventors: Köbe, Andreas, Oldenettel, Holger, Latarnik, Michael, Ernst, Gerhard, Fennel, Helmut, Becherer, Thomas, Huinink, Heinrich
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): ALLEN, ANDRE J
• Application Number:
  US09/514,254
• Time in Patent Office: 1,233 Days
• Field of Search: 731/46, 731/462, 731/463, 731/464, 731/465, 731/468, 340/441, 340/442, 340/443, 340/444, 340/445, 340/446, 340/447, 340/448
• US Class Current: 73/146
• CPC Class Codes: B60C 23/06 Signalling devices actuated by deformation of the tyre , e.g. tyre mounted deformation sensors or indirect determination of tyre deformation based on wheel speed, wheel-centre to ground distance or inclination of wheel axle
• CPC Class Codes: B60C 23/061 by monitoring wheel speed measuring distance traversed on the ground by vehicles G01C22/00
• CPC Class Codes: B60C 23/062 Frequency spectrum analysis of wheel speed signals, e.g. using Fourier transformation

Abstract

System and method for ascertaining the emergency running condition of a pneumatic tire on a motor vehicle. The system includes at least one sensor device arranged at least on each axle. The at least one sensor device is adapted to supply a permanently present first periodic oscillation proportional to a wheel rotation speed as a speed output signal. The at least one sensor device includes one of an active and a passive magnetic field sensor being mounted to one of rotate with the tire and be stationary. The transmitter device is arranged complementary to the at least one passive and active magnetic field sensor and is adapted to produce a periodic magnetic field change in proportion to the wheel rotation speed in a detection range. At least one signal processing device is used for processing and evaluating the speed output signal. A transmission and a display device are used for at least one of the transmission and the display of the speed output signal, and for one of the transmission and the display of at least one of the output control and the warning signal. An emergency running device is arranged on the vehicle wheel.

Claims

1. A method for ascertaining the emergency running condition of a pneumatic tire on a motor vehicle, the method comprising:

producing a permanently present first periodic oscillation in at least each axle proportional to a wheel rotation speed as a speed output signal;

feeding the speed output signal to a signal processing device,

wherein in an emergency running condition, the process further comprises;

superimposing, on one of the first periodic oscillation and the speed output signal, at least one separately defined periodic oscillation related to the emergency running condition and proportional to an emergency running condition wheel rotation speed;

detecting the superimposition of the first periodic oscillation with the at least one separately defined periodic oscillation characteristic of the emergency running condition in the signal processing device; and

producing a warning signal.

2. The method of claim 1, wherein the speed output signal is produced using one of an active and a passive magnetic field sensor.

3. The method of claim 2, wherein the magnetic field sensor comprises an encoder.

4. The method of claim 2, wherein the magnetic field sensor comprises a rotating member a stationary member, the magnetic field sensor being situated on a part of the vehicle.

5. The method of claim 4, wherein the magnetic field sensor is positioned on a part of the vehicle which is either stationary or rotates with the wheel, the magnetic field sensor producing a periodic magnetic field change in proportion to the wheel rotation speed.

6. The method of claim 1, wherein the at least one separately defined periodic oscillation is produced by an emergency running device provided on the at least one wheel, the at least one separately defined periodic oscillation being produced when the wheel experiences one of damaged and a loss of air pressure.

7. The method of claim 6, wherein the at least one separately defined periodic oscillation is produced by an emergency running support element which is arranged inside a pneumatic tire and on a rim of the wheel, the emergency running support element comprising a rolling circumference with discontinuities.

8. The method of claim 7, wherein the discontinuities comprise one of cavities and concavities.

9. The method of claim 6, wherein the at least one separately defined periodic oscillation is produced as a result of at least one material reinforcement formed inside a tire body of the wheel.

10. The method of claim 9, wherein the at least one material reinforcement is arranged in a sidewall region of the tire body, the at least one material reinforcement comprising one of various layers and plies of strength supports which stabilize the tire body in the emergency running condition when the tire experiences damage or a loss of air pressure, the at least one material reinforcement having defined discontinuities distributed over a circumference region.

11. The method of claim 10, wherein the discontinuities comprise one of agglomerations of material and material voids.

12. The method of claim 9, wherein the at least one separately defined periodic oscillation is produced by a first number of discontinuities distributed uniformly over a circumference of the tire body.

13. The method of claim 9, wherein the at least one separately defined periodic oscillation is produced by each of a first number of discontinuities distributed uniformly over a circumference of the tire body and a second number of discontinuities, different from the first number, which are distributed uniformly over the circumference of the tire body.

14. The method of claim 1, further comprising comparing the speed output signal, after being processed in the signal processing device, with at least one reference and threshold value.

15. The method of claim 14, further comprising recognizing when the at least one reference or threshold value is exceeded and producing the warning signal when the reference or threshold value is exceeded.

16. The method of claim 14, wherein the comparing comprises comparing the speed output signal with a speed output signal of at least one other wheel, the at least one other wheel representing the at least one reference or threshold value.

17. The method of claim 8, wherein, in the signal processing device, the process further comprises:

calculating a wheel velocity for a stipulated time interval from the speed output signal;

comparing the wheel velocity with one of at least one reference wheel velocity and at least one threshold value, wherein the speed output signal is represented with an oscillation, and the process further comprises;

ascertaining and storing for several successive and defined wheel rotation angles, corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles;

within defined count times T_L containing several successive wheel rotation angles, calculating and storing an average wheel rotation velocity for at least one wheel rotation within the count times from the times ascertained for the partial rotations; and

comparing one of average wheel rotation velocities and their course with the at least one reference wheel velocity or the at least one threshold value,

wherein, when the at least one reference wheel velocity or the at least one threshold value is exceeded by the average wheel rotation velocity or the their coarse, a warning signal is activated.

18. The method of claim 8, wherein, in the signal processing device, the process further comprises:

ascertaining and storing for several successive and defined wheel rotation angles, corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles;

calculating and storing an average from several such successively ascertained times for at least one wheel rotation;

ascertaining deviations between the ascertained and stored times and the calculated and stored average; and

comparing the ascertained deviations with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the ascertained deviations, a warning signal is activated.

19. The method of claim 8, wherein, in the signal processing device, the process further comprises:

ascertaining and storing for several successive and defined wheel rotation angles, corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles;

ascertaining a pattern of the corresponding times for partial rotations of the wheel using a pattern recognition process; and

comparing the ascertained pattern with one of a reference pattern and at least one threshold value,

wherein, when the ascertained pattern deviates from the reference pattern or the at least one threshold value, a warning signal is activated.

20. The method of claim 8, wherein, in the signal processing device, the process further comprises:

ascertaining and storing for several successive and defined wheel rotation angles, corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles;

ascertaining and storing frequencies for the corresponding times for partial rotations of the wheel with the aid of at least one computer unit;

calculating and storing reciprocals of the frequencies;

calculating and storing averages of the frequencies; and

ascertaining and storing deviations between the reciprocals and the averages;

comparing the deviations with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the deviations, a warning signal is activated.

21. The method of claim 8, wherein, in the signal processing device, the process further comprises:

ascertaining and storing for several successive and defined wheel rotation angles, corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles;

ascertaining and storing a frequency spectrum of the corresponding times for partial rotations of the wheel with the aid of at least one computer unit;

ascertaining power spectral densities by performing a frequency analysis on the frequency spectrum;

integrating and storing the power spectral densities over certain selected frequency intervals with the aid of at least one computer unit; and

comparing the integrated power spectral densities with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the integrated power spectral densities, a warning signal is activated.

22. The method of claim 8, wherein, in the signal processing device, the process further comprises:

ascertaining and storing for several successive and defined wheel rotation angles, corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles;

calculating and storing momentary wheel velocities from the corresponding times for the partial rotations of the wheel with the aid of at least one computer unit;

calculating and storing averages from the momentary wheel velocities;

ascertaining and storing deviations between the momentary wheel velocities and the averages; and

comparing the deviations with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the deviations, a warning signal is activated.

23. The method of claim 8, wherein, in the signal processing device, the process further comprises:

ascertaining and storing for several successive and defined wheel rotation angles, corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles;

calculating and storing momentary wheel accelerations from the corresponding times for partial rotations of the wheel with the aid of at least one computer unit;

calculating and storing averages of the momentary wheel accelerations;

ascertaining deviations between the momentary wheel accelerations and one of the averages and a zero value; and

comparing the deviations with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the deviations, a warning signal is activated.

24. The method of claim 23, wherein the deviations are ascertained between the momentary wheel accelerations and zero values, the deviations being represented as time differences between the zero values which are measured in one of at least one time control device and at least one timer.

25. The method of claim 24, wherein the time differences undergo a rotation-synchronous averaging before being further processed, such that an average is obtained over several wheel rotations from the zero value times measured with respect to one wheel rotation at equal time intervals or at equal rotation angle intervals, which average is then a basis for further signal processing.

26. A system for ascertaining the emergency running condition of a pneumatic tire on a motor vehicle, the system comprising:

at least one sensor device arranged at least on each axle, the at least one sensor device adapted to supply a permanently present first periodic oscillation proportional to a wheel rotation speed as a speed output signal;

the at least one sensor device comprising one of an active and a passive magnetic field sensor being mounted to one of rotate with the tire and be stationary;

the at least one sensor device further comprising one of a magnetically active and passive transmitter device which rotates at the wheel rotation speed relative to a magnetic field sensor, the transmitter device being arranged complementary to the at least one passive and active magnetic field sensor and adapted to produce a periodic magnetic field change in proportion to the wheel rotation speed in a detection range;

at least one signal processing device for processing and evaluating the speed output signal, the signal processing device being adapted to produce one of an output control and a warning signal;

a transmission and a display device for at least one of the transmission and the display of the speed output signal, and for one of the transmission and the display of at least one of the output control and the warning signal; and

an emergency running device arranged on the vehicle wheel which, in an emergency running condition, is adapted to produce at least one separately defined periodic oscillation related to the emergency running condition and proportional to the emergency running condition wheel rotation speed,

wherein, in an emergency running condition, the at least one separately defined periodic oscillation is superimposed on one of the first periodic oscillation and or the speed output signal.

27. The system of claim 26, wherein the at least one signal processing device comprises at least one filtering device for filtering noise.

28. The system of claim 27, wherein the at least one signal processing device comprises at least one storage device for storing one of reference and threshold values.

29. The system of claim 28, wherein the at least one signal processing device comprises a comparator which, after processing, compares a respective speed output signal with one of at least one reference value and at least one threshold value, and detects a superimposition of the first periodic oscillation with the at least one separately defined periodic oscillation, such that when the reference value or the threshold value is exceeded, a warning signal is produced.

30. The system of claim 26, wherein the emergency running device comprises at least one emergency running support element arranged inside a tire of the wheel.

31. The system of claim 30, wherein the at least one emergency running support element is supported on a rim of the wheel and comprises an emergency running surface having a circumference and a plurality of defined discontinuities distributed over the circumference.

32. The system of claim 31, wherein the discontinuities comprise one of cavities and concavities.

33. The system of claim 26, wherein the emergency running device comprises at least one material reinforcement formed inside a tire body of the wheel.

34. The system of claim 33, wherein the at least one material reinforcement is arranged in a sidewall region of the tire body.

35. The system of claim 34, wherein the at least one material reinforcement has a plurality of defined discontinuities distributed over a circumference portion of the tire body and comprises one of various layers and plies of strength supports, such that the at least one material reinforcement is adapted to stabilize the tire in the emergency running condition.

36. The system of claim 35, wherein the defined discontinuities comprise one of material agglomerations and material voids.

37. The system of claim 31, wherein the defined discontinuities are distributed uniformly over the circumference.

38. The system of claim 31, wherein the defined discontinuities comprise a first number of discontinuities distributed uniformly over the circumference and a second number of discontinuities, different from the first number, distributed uniformly over the circumference.

39. The system of claim 26, wherein the speed output signal is an input signal for the signal processing device and the signal processing device further comprises:

one of at least one filter and at least one low-pass filter for filtering out high-frequency noise portions of the speed output signal;

one of at least one comparator circuit and at least one Schmitt trigger for converting the speed output signal into a single-pulse square wave signal;

one of at least one time control device and at least one timer which, for several successive and defined wheel rotation angles, measures corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles, with the times being measured by ascertaining time differences between two decreasing or increasing edges of the square wave signal that correlate with the times for the partial rotations;

at least one counting device connected in parallel to one of the at least one time control device and the at least one timer and receiving the single-pulse signal, the at least one counting device ascertaining one of the number of single pulses obtained and measured times within a defined count time T_L;

at least one storage devices for storing the measured corresponding times for partial rotations of the wheel and the number of single pulses obtained within several successive count times T_L;

a computer circuit for calculating and storing a average wheel rotation velocity within the count times T_L for at least one wheel rotation from the times ascertained for the partial rotations and their numbers within the count times T_L; and

a comparator for comparing one of the average wheel rotation velocity or their course with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the averaged wheel rotation velocity or their coarse, a warning signal is activated.

40. The system of claim 26, wherein the speed output signal is an input signal for the signal processing device and the signal processing device further comprises:

one of at least one filter and at least one low-pass filter for filtering out high-frequency noise portions of the speed output signal;

one of at least one comparator circuit and at least one Schmitt trigger for converting the speed output signal into a single-pulse square wave signal;

one of at least one time control device and at least one timer which, for several successive and defined wheel rotation angles, measures corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles, with the times being measured by ascertaining time differences between two decreasing or increasing edges of the square wave signal that correlate with the times for the partial rotations;

at least one storage device for storing the measured corresponding times for partial rotations of the wheel;

a computer circuit for calculating an average value from the measures corresponding times for partial rotations of the wheel and for calculating deviations of the measures corresponding times for partial rotations of the wheel from the average value; and

a comparator for comparing the deviations with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the deviations, a warning signal is activated.

41. The system of claim 26, wherein the speed output signal is an input signal for the signal processing device and the signal processing device further comprises:

one of at least one filter and at least one low-pass filter for filtering out high-frequency noise portions of the speed output signal;

one of at least one comparator circuit and at least one Schmitt trigger for converting the speed output signal into a single-pulse square wave signal;

one of at least one time control device and at least one timer which, for several successive and defined wheel rotation angles, measure corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles, with the times being measured by ascertaining time differences between two decreasing or increasing edges of the square wave signal that correlate with the times for the partial rotations;

at least one computer unit for calculating frequencies of the measured corresponding times for partial rotations of the wheel and taking the reciporocal of the frequencies;

at least one storage device for storing the calculated frequencies;

a computer circuit for calculating an average value of several successively calculated frequencies and for calculating deviations of the calculated frequencies from the average value; and

a comparator for comparing the deviations with one of at least one reference value and at least one threshold value,

wherein when the at least one reference value or the at least one threshold value is exceeded by the deviations, a warning signal is activated.

42. The system of claim 26, wherein the speed output signal is an input signal for the signal processing device and the signal processing device further comprises:

one of at least one filter and at least one low-pass filter for filtering out high-frequency noise portions of the speed output signal;

one of at least one comparator circuit and at least one Schmitt trigger for converting the speed output signal into a single-pulse square wave signal;

one of at least one time control device and at least one timer which, for several successive and defined wheel rotation angles, measure corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles, with the times being measured by ascertaining time differences between two decreasing or increasing edges of the square wave signal that correlate with the times for the partial rotations;

at least one computer unit for carrying out a frequency analysis of a frequency spectrum of the measured corresponding times for partial rotations of the wheel as a function of a time or time signal and for ascertaining power spectral densities;

at least one computer unit for integrating the power spectral densities ascertained over certain selected frequency intervals;

at least one storage device for storing several successively ascertained integrals; and

a comparator for comparing the ascertained integrals with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the ascertained integrals, a warning signal is activated.

43. The system of claim 26, wherein the speed output signal is an input signal for the signal processing device and the signal processing device further comprises:

one of at least one filter and at least one low-pass filter for filtering out high-frequency noise portions of the speed output signal;

one of at least one comparator circuit and at least one Schmitt trigger for converting the speed output signal into a single-pulse square wave signal;

one of at least one time control device and at least one timer which, for several successive and defined wheel rotation angles, measure corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles, with the times being measured by ascertaining time differences between two decreasing or increasing edges of the square wave signal that correlate with the times for the partial rotations;

a computer circuit for calculating momentary wheel velocities of the measured corresponding times for partial rotations of the wheel;

at least one storage device for storing calculated momentary wheel velocities;

a computer circuit for calculating an average value of the momentary wheel velocities and for calculating deviations of the momentary wheel velocities from the average value; and

a comparator for comparing the deviations with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the deviations, a warning signal is activated.

44. The system of claim 26, wherein the speed output signal is an input signal for the signal processing device and the signal processing device further comprises:

one of at least one filter and at least one low-pass filter for filtering out high-frequency noise portions of the speed output signal;

one of at least one comparator circuit and at least one Schmitt trigger for converting the speed output signal into a single-pulse square wave signal;

one of at least one time control device and at least one timer which, for several successive and defined wheel rotation angles, measure corresponding times for partial rotations of the wheel determined by the defined wheel rotation angles, with the times being measured by ascertaining time differences between two decreasing or increasing edges of the square wave signal that correlate with the times for the partial rotations;

a computer circuit for calculating momentary wheel accelerations of the measured corresponding times for partial rotations of the wheel;

at least one storage device for storing calculated momentary wheel accelerations;

a computer circuit for calculating an average value of the momentary wheel accelerations and for calculating deviations of the momentary wheel accelerations from the average value; and

a comparator for comparing the deviations with one of at least one reference value and at least one threshold value,

wherein, when the at least one reference value or the at least one threshold value is exceeded by the deviations, a warning signal is activated.

45. The system of claim 26, wherein the speed output signal is fed from some portion of an anti-locking braking system.

46. The system of claim 26, wherein an anti-locking braking system is coupled to the signal processing device.

47. A method for ascertaining an emergency running condition of a pneumatic tire on a motor vehicle, the method comprising:

sensing a permanently present first periodic oscillation proportional to a wheel rotation speed of at least one wheel of the motor vehicle, the at least one wheel comprising an emergency running device which produces at least one periodic oscillation characteristic of an emergency running condition when the wheel experiences substantial damage or a substantial loss of air pressure, the sensing being performed by at least one sensor device disposed adjacent the at least one wheel;

feeding a speed output signal from the at least one sensor device to at least one filter which filters out high-frequency noise portions of the speed output signal;

converting the speed output signal into a square wave signal of single pulses using one of at least comparator circuit and at least one Schmitt trigger;

processing the single pulses using at least one processing device and producing at least one output;

storing the at least one output in a storage device;

subjecting the at least one output to a calculation with a computer circuit to produce at least one value;

comparing the at least one value with one of at least one reference value and at least one threshold value using a comparator; and

producing at least one warning signal on a display device when the at least one value exceeds the at least one reference value or the at least one threshold value,

wherein the at least one warning signal is produced when the tire experiences the emergency running condition.

48. The method of claim 47, wherein the processing is performed by two processing devices, one processing device comprising a time control device and the other processing device comprising a counting device.

49. The method of claim 47, wherein the processing is performed by the at least one processing device which comprising a time control device.

50. The method of claim 47, wherein the processing is performed by two processing devices, one processing device comprising a time control device and the other processing device comprising a computer which utilizes a formula.

51. A method for ascertaining an emergency running condition of a pneumatic tire on a motor vehicle, the method comprising:

sensing a permanently present first periodic oscillation proportional to a wheel rotation speed of at least one wheel of the motor vehicle, the at least one wheel comprising an emergency running device which produces at least one periodic oscillation characteristic of an emergency running condition when the wheel experiences substantial damage or a substantial loss of air pressure, the sensing being performed by at least one sensor device disposed adjacent the at least one wheel;

feeding a speed output signal from the at least one sensor device to at least one filter which filters out high-frequency noise portions of the speed output signal;

converting the speed output signal into a square wave signal of single pulses using one of at least one comparator circuit and at least one Schmitt trigger;

processing the single pulses using one of at least one time control device and at least one timer and producing a frequency spectrum;

feeding the frequency spectrum to a computer and performing a frequency analysis using a Fourier transform to ascertain power spectral densities;

integrating the power spectral densities using a computer and an integral so as to produce ascertained integrals;

feeding the ascertained integrals to at least one a storage device;

comparing the ascertained integrals with one of at least one reference value and at least one threshold value using a comparator; and

producing at least one warning signal on a display device when the ascertained integrals exceed the at least one reference value or the at least one threshold value,

wherein the at least one warning signal is produced when the tire experiences the emergency running condition.

52. A system for ascertaining an emergency running condition of a pneumatic tire on a motor vehicle, the system comprising:

a plurality of wheel sensor devices disposed on the vehicle, each wheel sensor device comprising;

one of an active or passive magnetic field sensor being disposed adjacent each wheel of the vehicle, each wheel sensor device supplying a permanently present first periodic oscillation in proportion to a wheel rotation speed in the form of a speed output signal;

a signal processing device receiving the speed output signal, the signal processing device comprising;

a plurality of low-pass filters for filtering out high-frequency noise portions of the speed output signal;

a Schmitt trigger connected to each low-pass filter;

a time control device connected to each Schmitt trigger;

a storage device connected to the time control devices;

a computer circuit connected to the storage device;

a comparator connected to the computer circuit; and

a display connected to the comparator,

wherein the signal processing device processes and evaluates the speed output signal, the signal processing device being adapted to produce a warning signal on the display device when the wheel experiences the emergency running condition.

53. The system of claim 52, wherein the signal processing device further comprises a counting device connected to each Schmitt trigger and connected to the storage device.

54. The system of claim 52, wherein the signal processing device further comprises a computer using a formula connected to each Schmitt trigger and connected to the storage device.

55. The system of claim 52, further comprising an emergency running device disposed on each wheel.

56. The system of claim 55, wherein the emergency running device comprises at least one emergency running support element arranged inside a tire of the wheel.

57. The system of claim 56, wherein the emergency running support element is supported on a rim of the wheel and comprises an emergency running surface having a circumference and a plurality of defined discontinuities distributed over the circumference.

58. A system for ascertaining the emergency running condition of a pneumatic tire on a motor vehicle, the system comprising:

a plurality of wheel sensor devices disposed on the vehicle, each wheel sensor device comprising;

one of an active or passive magnetic field sensor being disposed adjacent each wheel of the vehicle, each wheel sensor device supplying a permanently present first periodic oscillation in proportion to a wheel rotation speed in the form of a speed output signal;

a signal processing device receiving the speed output signal, the signal processing device comprising;

a plurality of low-pass filters for filtering out high-frequency noise portions of the speed output signal;

a Schmitt trigger connected to each low-pass filter;

a time control device connected to each Schmitt trigger;

a computer utilizing a Fourier transform connected to each time control devices;

a computer utilizing an integral connected to the computer utilizing the Fourier transform;

a storage device connected to the computer utilizing the integral;

a comparator connected to the storage device; and

a display connected to the comparator,

wherein the signal processing device processes and evaluates the speed output signal, the signal processing device being adapted to produce a warning signal on the display device when the wheel experiences an emergency running condition.

59. The system of claim 58, further comprising an emergency running device disposed on each wheel.

60. The system of claim 59, wherein the emergency running device comprises at least one emergency running support element arranged inside a tire of the wheel.

61. The system of claim 60, wherein the emergency running support element is supported on a rim of the wheel and comprises an emergency running surface having a circumference and a plurality of defined discontinuities distributed over the circumference.