System and method for tire/road friction estimation
First Claim
1. A method of friction estimation for a vehicle, the method comprising:
- using a model having a plurality of estimated parameters to establish a relationship between tire force and tire slip;
determining an actual tire force and an actual tire slip;
assessing the importance of each of the parameters at the actual tire force and slip;
determining which of the parameters to update based on the assessed importance of each of the parameters; and
updating the value of each parameter that it is determined should be updated.
1 Assignment
0 Petitions
Accused Products
Abstract
A system for friction estimation in a vehicle is disclosed generally comprising the use of a model having a plurality of estimated parameters to establish a relationship between tire force and tire slip and determining an actual tire force and slip. The importance of each of the parameters is assessed at the actual tire force and slip, which allows the system to determine which of the parameters significantly affect the slip-force relationship, and thus, should be updated. At some times, a particular parameter is especially important for the particular slip range, while at others, more than one parameter is updated. In some cases, a forced excitation of the system is produced to facilitate accurate estimation of parameters that change rapidly.
-
Citations
35 Claims
-
1. A method of friction estimation for a vehicle, the method comprising:
-
using a model having a plurality of estimated parameters to establish a relationship between tire force and tire slip;
determining an actual tire force and an actual tire slip;
assessing the importance of each of the parameters at the actual tire force and slip;
determining which of the parameters to update based on the assessed importance of each of the parameters; and
updating the value of each parameter that it is determined should be updated. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A system for friction estimation for a vehicle, comprising:
-
a control unit operative to establish a relationship between tire force and tire slip using a model having a plurality of estimated parameters; and
at least one input by which said control unit receives at least one signal representing an actual tire force and an actual tire slip;
wherein said control unit is operative to assess the importance of each of the parameters at the actual tire force and slip, to determine which of the parameters to update based on the assessed importance of each of the parameters, and to update the value of each parameter that it is determined should be updated. - View Dependent Claims (19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35)
-
Specification