A slip control method and arrangement for a drivetrain including a continuously variable transmission, forward-reverse clutch arrangement and an optional three-speed gearbox is described herein. The forward-reverse clutch arrangement includes a clutch that is so controlled as to slip when a torque higher than the usable torque attempts to pass through. Accordingly, the clutch prevents the prime mover from stalling.

A system for a vehicle includes a desired pressure module, a valve actuation module, a filter module, and a capacity detection module. The desired pressure module selectively generates an increase in a desired pressure of hydraulic fluid for a clutch of an automatic transmission. The valve actuation module actuates a solenoid valve based on the desired pressure. The solenoid valve supplies hydraulic fluid to a regulator valve, and the regulator valve supplies hydraulic fluid to the clutch. The filter module filters an acceleration of a shaft of the automatic transmission to generate a filtered acceleration. The capacity detection module indicates whether the clutch reached torque carrying capacity based on the filtered acceleration.

To allow a rider to sense torque in a low-speed traveling mode, a control device has a forward-and-reverse clutch oil pressure controller. In a low-speed traveling mode, the forward-and-reverse clutch oil pressure controller performs hunting control on driving torque, which is transmitted to a rear wheel from a crankshaft of an engine through a clutch device, a transmission, and a drive shaft, if vehicle speed stays within a second vehicle speed range for a predetermined time.

A slip control method and arrangement for a drivetrain including a continuously variable transmission, forward-reverse clutch arrangement and an optional three-speed gearbox is described herein. The forward-reverse clutch arrangement includes a clutch that is so controlled as to slip when a torque higher than the usable torque attempts to pass through. Accordingly, the clutch prevents the prime mover from stalling.

A vehicle includes a transmission, an engine, a disconnect clutch, an inertial measurement unit, and a controller. The transmission has an input shaft and an output shaft. The engine is configured to generate and deliver torque to the input shaft. The disconnect clutch is configured to connect and disconnect the engine from the input shaft. The disconnect clutch is also configured to crank the engine during an engine start. The inertial measurement unit is configured to measure inertial forces exerted onto the vehicle. The controller is programmed to, in response to a command to adjust a torque of the disconnect clutch to a desired value that is derived from the inertial forces and a vehicle velocity, drive the clutch actuator pressure to a value that corresponds to the desired value.

Clutch temperature management in a slip control method and arrangement for a drivetrain including a continuously variable transmission is described herein. The drivetrain includes a clutch that is so controlled as to slip when a torque higher than the usable torque attempts to pass through. The temperature data from the clutch is used to determine the usable torque. Accordingly, the clutch prevents the prime mover from stalling.

A friction engagement element control system is provided, which includes a friction engagement element including friction plates, and an actuation system configured to engage an input-side friction plate with an output-side friction plate with a pushing force, the friction plates having a negative slope characteristic in which a friction coefficient thereof decreases as a rotational difference between the friction plates increases, a rotational difference sensor of the friction engagement element, a separator configured to divide a variation in the detected rotational difference into a high-frequency component that is a vibration component and other low-frequency components, and a controller configured to control a pushing force only for the vibration component of the rotational difference so that the negative slope characteristic becomes a positive slope characteristic in which a frictional force of the friction engagement element decreases as the rotational difference decreases, when engaging the friction engagement element.

A vehicle includes a transmission, an engine, a disconnect clutch, an inertial measurement unit, and a controller. The transmission has an input shaft and an output shaft. The engine is configured to generate and deliver torque to the input shaft. The disconnect clutch is configured to connect and disconnect the engine from the input shaft. The disconnect clutch is also configured to crank the engine during an engine start. The inertial measurement unit is configured to measure inertial forces exerted onto the vehicle. The controller is programmed to, in response to a command to adjust a torque of the disconnect clutch to a desired value that is derived from the inertial forces and a vehicle velocity, drive the clutch actuator pressure to a value that corresponds to the desired value.

A clutch includes a first clutch half, a second clutch half, a first magnet arranged on the first clutch half, and a second magnet arranged on the second clutch half. The first and second magnets interact to enable a contactless detection of a state of wear of the clutch.

A method for determining a kiss point is disclosed. A drive unit having one or more motors with a motor output shaft is provided. One or more actuation profiles are ran and an amount of motor current and motor shaft position data is measured. The data measured is filtered and one or more motor current vs. motor shaft position plots having one or more curves with a high force and high current region are generated. A derivative is calculated over the curves and a slope of the high force and high current region is determined. A relative slope threshold is determined by multiplying the slopes by a predetermined percentage. One or more lines having a slope substantially equal to the relative slope threshold are plotted. The kiss point is determined based on the position of the motor shaft where the derivative of the curves equals the slope of the lines plotted.