Brake control method and brake control device
First Claim
1. A brake control method for a braking device having a function of applying a brake force to a wheel equipped with a tire to put a brake on the wheel while adjusting the brake force, the brake control method comprising the steps of:
- acquiring, in time series, acceleration data of acceleration acting on the tire in a radial direction of the tire, due to rotation of the tire;
calculating a contact lengths of the tire based on the acceleration data for every round of rotation of the tire; and
controlling the brake force, according to comparative judgment information obtained by comparing a plurality of contact lengths of the tire thus calculated, with one another,wherein, the brake force is controlled when one of conditions 1 to 3 is met, in whichthe condition 1 is that assuming that a contact length in a state where the brake force is not applied or in a state immediately after an application of the brake force is set as a reference contact length, a contact length calculated after an application of the brake force is longer than a length determined by multiplying the reference contact length by a predetermined value,the condition 2 is that, assuming that a contact length at a preceding time is set to Li−
1 and a following contact length calculated first after the preceding time is set to Li among the contact length calculated after an application of the brake force, the following contact length Li satisfies 1.02×
Li−
1>
Li>
0.97×
Li−
1, andthe condition 3 is that assuming that a contact length calculated for every round of rotation of the tire after an application of the brake force is set to Li and a maximum length of contact lengths calculated before a slip ratio of the tire reaches a maximum value thereof is set to Lmax, the contact length Li does not satisfy 1.1×
Lmax>
Li>
0.9×
Lmax.
1 Assignment
0 Petitions
Accused Products
Abstract
A brake control device includes a braking device provided to a wheel, the braking device having a function of applying a brake force to the wheel while adjusting the brake force. The brake control device includes: an acceleration sensor for outputting acceleration data of acceleration acting on the rotating tire in a radial direction of the tire; a contact length calculating unit for calculating contact lengths of the tire based on the acceleration data; a brake sensor for detecting that a brake force is applied and for outputting a detection signal; a judging unit for outputting, to the braking device, a brake information signal for adjusting the brake force according to comparative judgment information which is obtained by comparing the calculated contact lengths; and a brake control unit for outputting a control signal for causing the braking device to adjust a brake force thereof according to the brake information signal.
17 Citations
7 Claims
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1. A brake control method for a braking device having a function of applying a brake force to a wheel equipped with a tire to put a brake on the wheel while adjusting the brake force, the brake control method comprising the steps of:
-
acquiring, in time series, acceleration data of acceleration acting on the tire in a radial direction of the tire, due to rotation of the tire; calculating a contact lengths of the tire based on the acceleration data for every round of rotation of the tire; and controlling the brake force, according to comparative judgment information obtained by comparing a plurality of contact lengths of the tire thus calculated, with one another, wherein, the brake force is controlled when one of conditions 1 to 3 is met, in which the condition 1 is that assuming that a contact length in a state where the brake force is not applied or in a state immediately after an application of the brake force is set as a reference contact length, a contact length calculated after an application of the brake force is longer than a length determined by multiplying the reference contact length by a predetermined value, the condition 2 is that, assuming that a contact length at a preceding time is set to Li−
1 and a following contact length calculated first after the preceding time is set to Li among the contact length calculated after an application of the brake force, the following contact length Li satisfies 1.02×
Li−
1>
Li>
0.97×
Li−
1, andthe condition 3 is that assuming that a contact length calculated for every round of rotation of the tire after an application of the brake force is set to Li and a maximum length of contact lengths calculated before a slip ratio of the tire reaches a maximum value thereof is set to Lmax, the contact length Li does not satisfy 1.1×
Lmax>
Li>
0.9×
Lmax. - View Dependent Claims (2, 3)
-
-
4. A brake control device, comprising:
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a braking device provided to a wheel equipped with a tire, the braking device having a function of applying a brake force to the wheel to put a brake on the wheel while adjusting the brake force; an acceleration sensor for outputting, in time series, acceleration data of acceleration acting on the tire in a radial direction of the tire due to rotation of tire; a contact length calculating unit, to which the acceleration data is input, for calculating a contact length of the tire based on the acceleration data for every round of rotation of the tire; a brake sensor for detecting that the brake force is applied by the braking device and for outputting a detection signal; a judging unit connected to the brake sensor, for outputting, to the braking device, a brake information signal indicating whether it is necessary or not to adjust the brake force, according to comparative judgment information which is obtained by comparing calculated contact lengths of the tire, in a case where the detection signal is input from the brake sensor; and a brake control unit connected to the judging unit, for outputting a control signal for causing the braking device to adjust the brake force thereof, according to the brake information signal output from the judging unit, wherein, the judging unit outputs the brake information signal to the brake control unit when one of conditions 1 to 3 is met, in which the condition 1 is that assuming that a contact length in one of a state where the brake force is not applied and in a state immediately after the application of the brake force is set as a reference contact length, a contact length calculated after the application of the brake force is longer than a length determined b multiplying the reference contact length by a predetermined value and the detection signal is input from the brake sensor, the condition 2 is that assuming that a contact length at a preceding time is set to Li−
1 and a following contact length calculated first after the preceding time is set to Li among contact lengths calculated after the application of the brake force the following contact length L satisfies 1.02×
Li−
1>
Li>
0.97×
Li−
1 and the detection signal is input from the brake sensor, andthe condition 3 is that assuming that a contact length calculated for eve round of rotation of the tire after the application of the brake force is set to Li and a maximum length of contact lengths calculated before a slip ratio of the tire reaches a maximum value thereof is set to Lmax, the contact length Li does not satisfy 1.1×
Lmax>
Li>
0.9×
Lmax and the detection signal is input from the brake sensor. - View Dependent Claims (5, 6, 7)
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Specification