Clutch engagement ratio detection

1 . A method for determining a clutch engagement ratio for a vehicle having at least a front wheel and a rear wheel, a motor, a transmission, and a clutch coupling the motor to the transmission, the method comprising:

receiving, at a controller, an output transmission speed;

receiving, at the controller, an input transmission speed;

calculating, with the controller, a transmission speed ratio by comparing the output transmission speed to the input transmission speed;

receiving, at the controller, a signal associated with a currently engaged gear in the transmission;

extracting, with the controller, a gear speed ratio associated with the currently engaged gear;

comparing the transmission speed ratio to the gear speed ratio;

extrapolating a clutch engagement ratio from the comparison of the transmission speed ratio to the gear speed ratio; and

determining a clutch condition based on the clutch engagement ratio.

2 . The method of claim 1 , wherein receiving the output transmission speed further comprises receiving a signal associated with a sensed speed of a wheel engaged with the transmission.

3 . The method of claim 1 , wherein receiving the input transmission speed further comprises receiving a signal from a shaft encoder coupled to an output shaft of the motor associated with a detected speed of the motor.

4 . The method of claim 1 , wherein extracting the gear speed ratio comprises extracting the gear speed ratio from a set of gear ratios stored in a detection memory of the controller.

5 . The method of claim 1 , wherein determining the clutch condition comprises determining that the transmission speed ratio matches the gear speed ratio, and the transmission is engaged.

6 . The method of claim 5 , further comprising activating a closed clutch flag.

7 . The method of claim 1 , wherein determining the clutch condition comprises determining that the transmission speed ratio differs from the gear speed ratio, and the clutch condition is either a slipping clutch or an open clutch, and activating one of a slipping clutch flag or an open clutch flag based on whether the clutch engagement ratio satisfies a predetermined clutch threshold.

8 . The method of claim 7 , wherein a clutch engagement ratio ranging from 0 to 0.5 is associated with the slipping clutch flag.

9 . The method of claim 7 , wherein when the slipping clutch flag is activated, an amount of torque output delivered to the rear wheel changes.

10 . The method of claim 7 , wherein when the slipping clutch flag is activated, a brake for the vehicle is engaged.

11 . The method of claim 7 , wherein when the slipping clutch flag is activated a speed of the motor decreases.

12 . The method of claim 7 , wherein a clutch engagement ratio ranging from 0.5 to 1 is associated with the open clutch flag.

13 . The method of claim 7 , wherein the open clutch flag is an indicator associated with a safe start scenario.

14 . The method of claim 7 , wherein the open clutch flag is an indicator associated with a safe shift scenario.

15 . The method of claim 7 , further comprising receiving, at the controller, a signal associated with a current acceleration and comparing the current acceleration to an expected acceleration.

16 . The method of claim 15 , further comprising confirming the slipping clutch flag when a reduction in acceleration is detected.

17 . The method of claim 1 , further comprising receiving, at the controller, an amount of clutch lever pull and comparing the amount of clutch lever pull to the clutch engagement ratio.

18 . The method of claim 1 , further comprising:

determining a clutch ratio threshold;

activating an open clutch flag when the clutch engagement ratio is between the clutch ratio threshold and 1;

activating a slipping clutch flag when the clutch engagement ratio is greater than 0 and less than or equal to the clutch ratio threshold; and

activating a closed clutch flag when the clutch engagement ratio is equal to 1.

19 . A method for determining a clutch condition for a vehicle having at least a front wheel and a rear wheel, a motor, a transmission, and a clutch coupling the motor to the transmission, the method comprising:

determining, with a controller, an output transmission speed;

determining, with the controller, an input transmission speed;

determining, with the controller, a transmission speed ratio by comparing the output transmission speed to the input transmission speed;

determining, with the controller, a currently engaged gear in the transmission;

extracting a gear speed ratio associated with the currently engaged gear from a stored set of gear ratios;

determining, with the controller, a clutch engagement ratio by comparing the transmission speed ratio to the gear speed ratio;

determining, with the controller, a clutch condition based on the clutch engagement ratio;

receiving, at the controller, a signal associated with a current acceleration and comparing the current acceleration to an expected acceleration; and

confirming, with the controller, the clutch condition based on the comparison of the current acceleration and the expected acceleration.

20 . The method of claim 19 , further comprising:

determining a clutch ratio threshold;

activating an open clutch flag when the clutch engagement ratio is between the clutch ratio threshold and 1;

activating a slipping clutch flag when the clutch engagement ratio is greater than 0 and less than or equal to the clutch ratio threshold; and

activating a closed clutch flag when the clutch engagement ratio is equal to 1.