Brake control device, brake control method, and recording medium

A brake control device of a vehicle which applies a braking force to a wheel mounted with a tire to brake the vehicle, comprising:

• a memory device storing therein a friction characteristic of the tire with respect to a vehicle velocity of the vehicle or a wheel velocity of the wheel;
• a detecting unit for detecting the vehicle velocity of the vehicle and the wheel velocity of the wheel;
• a signal generating unit for, when the braking force is applied to the wheel, finding a slip velocity based on the vehicle velocity and the wheel velocity detected by the detecting unit and, finding an optimum slip velocity, at which a maximum friction force is generated by the tire at the vehicle velocity or the wheel velocity detected by the detecting device, by using the characteristic called from the memory device and, if a difference found by subtracting the optimum slip velocity from the found slip velocity is equal to or more than a predetermined value, generating a control signal for controlling the braking force according to the difference;
• and
• a braking unit for controlling the braking force based on the generated control signal to adjust the wheel velocity.

A brake control method for a vehicle which applies a braking force to a wheel mounted with a tire to brake the vehicle, comprising:

• detecting a vehicle velocity of the vehicle and a wheel velocity of the wheel;
• finding a slip ratio based on the detected vehicle velocity and wheel velocity;
• when the braking force is applied to the wheel, finding an optimum slip ratio at which a maximum friction force is generated by the tire at the detected vehicle velocity or wheel velocity, by using a friction characteristic of the tire with respect to the vehicle velocity or the wheel velocity;
• if a difference found by subtracting the optimum slip ratio from the found slip ratio is equal to or more than a predetermined value, generating a control signal for controlling the braking force according to the difference;
• and
• controlling the braking force based on the generated control signal to adjust the wheel velocity.

A brake control method for a vehicle which applies a braking force to a wheel mounted with a tire to brake the vehicle, comprising:

• detecting a vehicle velocity of the vehicle and a wheel velocity of the wheel;
• finding a slip velocity based on the detected vehicle velocity and wheel velocity;
• when the braking force is applied to the wheel, finding an optimum slip velocity, at which a maximum friction force is generated by the tire at the detected vehicle velocity or wheel velocity, by using a friction characteristic of the tire with respect to the vehicle velocity or the wheel velocity;
• if a difference found by subtracting the optimum slip velocity from the found slip velocity is equal to or more than a predetermined value, generating a control signal for controlling the braking force according to the difference;
• and
• controlling the braking force based on the generated control signal to adjust the wheel velocity.

A recording medium having recorded therein a computer readable program for causing a computer to perform adjustment of a braking force, when the braking force is applied to a wheel mounted with a tire to brake a vehicle,

• wherein the program includes:
• a procedure for causing a computing unit of the computer to calculate a slip ratio based on a vehicle velocity of the vehicle and a wheel velocity of the wheel;
• a procedure for calling a friction characteristic of the tire with respect to the vehicle velocity or the wheel velocity stored in a memory device of the computer in advance and causing the computing unit to calculate an optimum slip ratio, at which a maximum friction force is generated by the tire at the vehicle velocity or the wheel velocity, by using the called characteristic;
• a procedure for, if a difference found by subtracting the optimum slip ratio from the calculated slip ratio is equal to or larger than a predetermined value, causing the computing unit to generate a control signal for controlling the braking force according to the difference.

A recording medium having recorded therein a computer readable program for causing a computer to perform adjustment of a braking force, when the braking force is applied to a wheel mounted with a tire to brake a vehicle,

• wherein the program includes:
• a procedure for causing a computing unit of the computer to calculate a slip velocity based on a vehicle velocity of the vehicle and a wheel velocity of the wheel;
• a procedure for calling a friction characteristic of the tires with respect to the vehicle velocity or the wheel velocity stored in a memory device of the computer in advance and causing the computing unit to calculate an optimum slip velocity, at which a maximum friction force is generated by the tire at the vehicle velocity or the wheel velocity, by using the called characteristic;
• a procedure for, if a difference found by subtracting the optimum slip velocity from the calculated slip velocity is equal to or larger than a predetermined value, causing the computing unit to generate a control signal for controlling the braking force according to the difference.