Abstract The invention relates to a method for filtering out disturbances in the form of short term wheel acceleration signals when the wheel exhibits an overall deceleration, so that a more accurate deceleration signal can be used for control of drive slippage. Wheel speed v is measured at intervals T A and speed changes for each interval are determined. When a change is negative or zero following a positive change in a previous interval, the wheel speed is stored as a maximum speed v max while v continues to be measured and a counter determines the period of time Δt between the occurrence of v max and the instantaneous value v. Beginning at a predetermined filtering time ΔT after storing v max , a quotient Δv/Δt representing the filtered slope of the value v is determined and used as a control variable to regulate wheel slippage.
Inventors
👤 Jochen Schafer
👤 Thomas Frank
👤 Frank Bederna
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-05 01:20
CPC Classifications
B; B60; B60L; B60L3/00; B60L3/10
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
141 words
Method for controlling wheel slippage in a vehicle comprising determining the speed of a driven wheel and producing an instantaneous digital wheel speed value v at time points displaced by measurement intervals T A , determining the speed change during each measurement interval T A , storing said value v as a maximum v max when said speed change is equal to or less than zero in a measurement interval T A immediately following an interval T A in which a speed change greater than zero was determined, determining a difference Δv =v max -v, determining a quotient Δv/Δt beginning at predetermined filtering time ΔT after storing v max , where At is elapsed time after storing v max said quotient representing a filtered slope of the value v, and using said quotient as a control variable to regulate wheel slippage.
Claim 2
Dependent Claim
141 words
Method for controlling wheel slippage in a vehicle comprising determining the speed of a driven wheel and producing an instantaneous digital wheel speed value v at time points displaced by measurement intervals T A , determining the speed change during each measurement interval T A , storing said value v as a maximum v max when said speed change is equal to or less than zero in a measurement interval T A immediately following an interval T A in which a speed change greater than zero was determined, determining a difference Δv =v max -v, determining a quotient Δv/Δt beginning at predetermined filtering time ΔT after storing v max , where At is elapsed time after storing v max said quotient representing a filtered slope of the value v, and using said quotient as a control variable to regulate wheel slippage.
Claim 3
Dependent Claim
32 words
Method as in claim 1 further comprising comparing said wheel speed value v to a threshold value and determining said quotient Δv/Δt only when said wheel speed value exceeds said threshold value.
Claim 4
Dependent Claim
30 words
Method as in claim 1 wherein said wheel speed signal exhibits a disturbance characterized by an expected period, said predetermined filtering time ΔT being greater than half the expected period.
Claim 5
Dependent Claim
26 words
Method as in claim 1 further comprising comparing said quotient Δv/Δt to a threshold value and producing an intervention signal when the threshold value is exceeded.
Claim 6
Dependent Claim
28 words
Method as in claim 1 further comprising comparing said period of time Δt to a threshold value and producing an intervention signal when the threshold value is exceeded.
Claim 7
Dependent Claim
30 words
Method as in claim 1 further comprising comparing said quotient Δv/Δt to a deceleration threshold value and erasing the stored value v max when said quotient exceeds a predetermined threshold.
Claim 8
Dependent Claim
38 words
Method as in claim 1 further comprising comparing said period of time Δt to a predetermined period of time and erasing the stored value v max when said period of time Δt exceeds said predetermined period of time.