Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
  • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
  • B60T8/17—Using electrical or electronic regulation means to control braking
  • B60T8/173—Eliminating or reducing the effect of unwanted signals, e.g. due to vibrations or electrical noise

Definitions

• the invention relates to a method for detecting wheel vibrations for use in anti-lock control systems according to the preamble of claim 1 and an associated system.
• Wheel vibrations have a significant impact on wheel slip control systems.
• controller sizes such as wheel speeds, wheel differentiators can be filtered or corrected in order to improve the control comfort and the controller performance.
• Control times for the brake pressure control devices can be varied in the sense of damping the line vibrations.
• DE 196 20 581 AI shows, as a way of obtaining signals for the moments transmitted from the wheel to the road and / or for the instantaneous coefficient of friction, a device for determining the rotational behavior of a vehicle wheel, magnetizing surfaces or strips being provided on a tire. Transducers are attached to the body at two or more different positions in the direction of rotation and are also at a different distance from the axis of rotation of the wheel. If the tire is deformed as a result of the forces acting on the tire, a change in the phase position occurs between the measurement signals emitted by the sensors. This change in the phase position is evaluated as a measure of the moments transmitted from the wheel to the driving track and / or for the current row value.
• DE 196 20 581 AI thus shows tire sensors and signals detected by these tire sensors.
• Powertrain vibrations can be easily determined.
• a slip control can regulate the desired wheel slip in accordance with the physical course of the wheel. Malfunctions caused by tire vibrations have no influence on the controller performance.
• Figure 1 shows a block diagram of a system for
• FIGS 2a, 2b and 2c show illustrations for explaining the method according to the present invention.
• FIG. 1 shows a block diagram of a system for carrying out the method for detecting wheel vibrations according to the present invention.
• a tire 101 which is representative of all the tires on the vehicle: is provided with measuring surfaces (strips) 102, 103 with field lines, preferably with circumferential directions, as can be seen in FIG.
• the magnetizing surfaces 102, 103 can be in the tires 101 be incorporated or provided on the outside of the tire 101.
• the magnetization always takes place in sections in the same direction, but with the opposite orientation, ie it has an alternating polarity.
• the magnetizing surface with positive polarity is designated 102
• the magnetizing surface with negative polarity is designated 103.
• the magnetized strips 102 and 103 preferably run in the vicinity of the rim flange and in the region of the tire. The sensors 102 and 103 thus rotate at the wheel speed.
• Transducers 104 and 105 are attached to the body at two or more points that are different in the direction of rotation and also have a different radial distance from the axis of rotation or the wheel axis 100. This results in an inner signal si, which the sensor 104 detects in the vicinity of the wheel hub, and an outer signal sa, which detects the sensor 105 further away from the wheel hub.
• the signals si and sa are phase-shifted from one another with a phase position D, as shown in FIG. 2a.
• a rotation of the tire 101 is preferably detected in the circumferential direction via the changing polarity of the measurement signals si and sa.
• the detected measurement signals si and sa with their respective amplitudes and phases are fed to an evaluation unit 106 shown in FIG. 1 for determining speed signals and phase positions, which with the aid of the known inner and outer circumference of the tire 101 in accordance with the arrangement of the measurement sensors 104, 105, which are also called tire sensors, calculates respective speed signals vi and va, which can then each serve as an input signal for a wheel slip control system 108.
• the evaluation unit 106 furthermore determines a change in the phase position from D + dl to D-d2, or vice versa, between the inner signal si and the outer signal sa, which change indicates a deformation of the tire 101 when driving or braking.
• the speed signals vi, va are also fed to a unit 110 for determining an oscillation amplitude and frequency. This determination is made by forming a difference va-vi between the speed signals vi and va.
• Vibration frequency calculated. If, in addition, a deformation of the tire is detected, which can be determined from a change in the phase position from D + dl to D-d2 between the inner signal si and the outer signal Sa according to the speeds vi and va, as described above with reference to FIG 2b and 2c is described, it is drive train vibrations that can shake the entire vehicle.
• the can Wheel slip control system 108 with suitable filter measures or
• Corrective measures calculate the control-relevant control deviation as the difference between the filtered speed signal of the slipping wheel and a reference speed Vref.
• the reference speed Vref can be determined as is known in the prior art. For example, it can be determined from the engine speed.
• vehicle-specific wheel speed profiles of different wheel vibrations can also be stored in the wheel slip control system 108 as a correlation of the values sa, si and va, vi, in order to immediately initiate controller damping measures when a vibration occurs.
• the correlation between a changing wheel load and the measurement signal allows the following direct reactions to a detected wheel vibration.
• the further control in the wheel slip control system 108 takes place as is known from the prior art, for example from DE 195 16 120 AI mentioned at the beginning.
• drive train vibrations are identified using measurement signals detected by means of tire sensors. This can cause a Vibration of the tire itself can be recognized, which was previously not possible in the prior art. According to the invention, the influence of disturbing vibrations on the behavior of a controller can be eliminated immediately.

Landscapes

• Engineering & Computer Science (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Regulating Braking Force (AREA)
• Measurement Of Mechanical Vibrations Or Ultrasonic Waves (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=7927866

Family Applications (1)

Country Status (5)

Families Citing this family (5)

Family Cites Families (5)

• 1999
  • 1999-11-04 DE DE19953030A patent/DE19953030B4/de not_active Expired - Fee Related
• 2000
  • 2000-08-05 JP JP2001534656A patent/JP2003512970A/ja not_active Withdrawn
  • 2000-08-05 WO PCT/DE2000/002632 patent/WO2001032483A1/de not_active Application Discontinuation
  • 2000-08-05 EP EP00963882A patent/EP1140596A1/de not_active Withdrawn
  • 2000-08-05 KR KR1020017008489A patent/KR20010089762A/ko not_active Application Discontinuation

Non-Patent Citations (1)

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