Straddled vehicle

A straddled vehicle comprising:

• a front wheel;
• at least one rear wheel;
• a driving source which generates a driving force and rotates the at least one rear wheel with the driving force;
• a braking device which lowers a rotation speed of at least the at least one rear wheel;
• a first detector which acquires and outputs a pitch rate, and acquires a bank angle and a yaw rate of the straddled vehicle;
• and
• a controller including a front wheel lift determination circuit which determines whether a front wheel lift exists or not based on the pitch rate, wherein
• the controller corrects the pitch rate to obtain a corrected pitch rate along a vertical direction, by using
• β′=β×cos(A)−γ×sin(A), wherein
• β is the pitch rate,
• β′ is the corrected pitch rate,
• A is the bank angle, and
• γ is the yaw rate,
• such that the front wheel lift determination circuit makes the determination based on the corrected pitch rate, and
• when the front wheel lift determination circuit determines that the front wheel lift exists, the controller reduces a driving force of the straddled vehicle by controlling the driving source or the braking device.

A straddled vehicle comprising:

• a front wheel;
• at least one rear wheel;
• a driving source which generates a driving force and rotates the at least one rear wheel with the driving force;
• a braking device which lowers a rotation speed of at least the at least one rear wheel;
• a first detector which acquires and outputs a pitch rate, and acquires a bank angle and a yaw rate of the straddled vehicle;
• a second detector which detects and outputs information concerning rotation of the front wheel;
• a third detector which detects and outputs at least one output that includes at least one of a rotation speed of the at least one rear wheel, a rotation rate of the driving source, and an acceleration of the straddled vehicle along a longitudinal direction;
• and
• a controller including a front wheel lift determination circuit which monitors respective outputs from the first detector, the second detector, and the third detector to determine whether a front wheel lift exists or not based on
• whether the pitch rate satisfies a first predetermined criteria, and whether the information concerning rotation of the front wheel satisfies a second predetermined criteria, and
• the at least one output from the third detector, wherein
• the controller corrects the pitch rate to obtain a corrected pitch rate along a vertical direction, by using
• β′=β×cos(A)−γ×sin(A), wherein
• β is the pitch rate,
• β′ is the corrected pitch rate,
• A is the bank angle, and
• γ is the yaw rate,
• such that the front wheel lift determination circuit makes the determination based on the corrected pitch rate, and
• when the front wheel lift determination circuit determines that the front wheel lift exists, the controller reduces a driving force of the straddled vehicle by controlling the driving source or the braking device.

A controller for controlling a driving source or a braking device of a straddled vehicle, the straddled vehicle including

• a front wheel,
• a rear wheel,
• a driving source which generates a driving force and rotates the rear wheel with the driving force,
• a braking device which lowers a rotation speed of at least the rear wheel,
• an inertia measurement device which acquires and outputs a pitch rate, and acquires a bank angle and a yaw rate of the straddled vehicle, and
• a front-wheel rotation speed sensor which detects and outputs a rotation speed of the front wheel,
• the controller comprising:
• a front wheel lift determination circuit which monitors the pitch rate and the rotation speed of the front wheel to determine whether a front wheel lift exists or not based on whether the pitch rate satisfies a first predetermined criteria, and whether the rotation speed of the front wheel satisfies a second predetermined criteria, wherein
• the controller corrects the pitch rate to obtain a corrected pitch rate along a vertical direction, by using
• β′=β×cos(A)−γ×sin(A), wherein
• β is the pitch rate,
• β′ is the corrected pitch rate,
• A is the bank angle, and
• γ is the yaw rate,
• such that the front wheel lift determination circuit makes the determination based on the corrected pitch rate, and
• when the front wheel lift determination circuit determines that the front wheel lift exists, the controller controls the driving source or the braking device so that the driving force is lowered or the rotation speed of the rear wheel is lowered.

A method of controlling a driving source or a braking device of a straddled vehicle, the straddled vehicle including

• a front wheel,
• a rear wheel,
• a driving source which generates a driving force and rotates the rear wheel with the driving force,
• a braking device which lowers a rotation speed of at least the rear wheel,
• an inertia measurement device which acquires and outputs a pitch rate, and acquires a bank angle and a yaw rate of the straddled vehicle, and
• a front-wheel rotation speed sensor which detects and outputs a rotation speed of the front wheel,
• the method comprising:
• monitoring the pitch rate and the rotation speed of the front wheel;
• correcting the pitch rate to obtain a corrected pitch rate along a vertical direction, by using
• β′=β×cos(A)−γ×sin(A), wherein
• β is the pitch rate,
• β′ is the corrected pitch rate,
• A is the bank angle, and
• γ is the yaw rate;
• determining a determination indicating whether a front wheel lift exists or not based on whether the corrected pitch rate satisfies a first predetermined criteria, and whether the rotation speed of the front wheel satisfies a second predetermined criteria;
• and
• when the determination indicates that the front wheel lift exists, controlling the driving source or the braking device so that the driving force is lowered or the rotation speed of the rear wheel is lowered.