Robust torque estimation using multiple models

Claim 1

A method of estimating wheel torque in a vehicle having a plurality of wheels, the vehicle being controlled by an electronic control unit having a memory, the method comprising the steps of: sensing at least one vehicle operating parameter to obtain an operating signal; modelling wheel torque utilizing at least two independent models to obtain a like plurality of individual torque estimate signals, each model generating an individual torque estimate signal based on the operating signal; weighting the individual torque estimate signals according to a predefined accuracy of the associated torque model to obtain a plurality of weighted individual torque estimate signals; generating a final torque estimate signal based on the weighted individual torque estimate signals; controlling vehicle operation based on the final torque estimate signal; said step of modelling including the step of generating a torque estimate by modelling vehicle dynamics; said step of generating including estimating wheel torque according to: τ.sub.w =(M.sub.v ·a+f(υ))·r wherein τ w =wheel torque, M.sub.υ represents vehicle mass, a=vehicle acceleration, f(υ)=losses due to rotational friction and wind drag, and r=the effective radius of the tire on the vehicle wheel.

Claim 2

A method of estimating wheel torque in a vehicle having a plurality of wheels, the vehicle being controlled by an electronic control unit having a memory, the method comprising the steps of: sensing at least one vehicle operating parameter to obtain an operating signal; modelling wheel torque utilizing at least two independent models to obtain a like plurality of individual torque estimate signals, each model generating an individual torque estimate signal based on the operating signal; weighting the individual torque estimate signals according to a predefined accuracy of the associated torque model to obtain a plurality of weighted individual torque estimate signals; generating a final torque estimate signal based on the weighted individual torque estimate signals; controlling vehicle operation based on the final torque estimate signal; said step of modelling including the step of generating a torque estimate by modelling vehicle dynamics; said step of generating including estimating wheel torque according to: τ.sub.w =(M.sub.v ·a+f(υ))·r wherein τ w =wheel torque, M.sub.υ represents vehicle mass, a=vehicle acceleration, f(υ)=losses due to rotational friction and wind drag, and r=the effective radius of the tire on the vehicle wheel.

Claim 6

A method of estimating wheel torque in a vehicle having a plurality of wheels, the vehicle being controlled by an electronic control unit having memory, the method comprising the steps of: sensing at least one vehicle operating parameter to obtain an operating signal; modelling wheel torque utilizing at least two independent models to obtain a like plurality of individual torque estimate signals, each model generating an individual torque estimate signal based on the operating signal; weighting the individual torque estimate signals according to a predefined accuracy of the associated torque model to obtain a plurality of weighted individual torque estimate signals: generating a final torque estimate signal based on the weighted individual torque estimate signals; controlling vehicle operation based on the final torque estimate signal; said vehicle including a torque converter, the step of modelling including the step of generating a torque estimate by modelling the torque converter as a torque meter; said step of generating including estimating wheel torque according to: τ.sub.w =τ.sub.t -J.sub.d ·α-τ.sub.b wherein τ w =wheel torque, τ t =turbine torque of the torque converter reelected at the wheel, τ b =braking torque, J d =inertia of vehicle drivetrain components downstream from the torque converter, and α=angular acceleration of a driven vehicle wheel.

Claim 7

A method of estimating wheel torque in a vehicle having a plurality of wheels, the vehicle being controlled by an electronic control unit having memory, the method comprising the steps of: sensing at least one vehicle operating parameter to obtain an operating signal; modelling wheel torque utilizing at least two independent models to obtain a like plurality of individual torque estimate signals, each model generating an individual torque estimate signal based on the operating signal; weighting the individual torque estimate signals according to a predefined accuracy of the associated torque model to obtain a plurality of weighted individual torque estimate signals: generating a final torque estimate signal based on the weighted individual torque estimate signals; controlling vehicle operation based on the final torque estimate signal; said vehicle including a torque converter, the step of modelling including the step of generating a torque estimate by modelling the torque converter as a torque meter; said step of generating including estimating wheel torque according to: τ.sub.w =τ.sub.t -J.sub.d ·α-τ.sub.b wherein τ w =wheel torque, τ t =turbine torque of the torque converter reelected at the wheel, τ b =braking torque, J d =inertia of vehicle drivetrain components downstream from the torque converter, and α=angular acceleration of a driven vehicle wheel.