A control system and method for a hybrid vehicle involve controlling a hybrid powertrain comprising an engine and a transmission having one or more electric motors and not comprising a decoupling mechanism therebetween, detecting an operating condition where the transmission is in neutral and the vehicle is moving at a speed less than a low speed threshold, and in response to detecting the operating condition: determining a desired propulsive torque of the powertrain, determining an actual propulsive torque at the driveline, calculating a torque difference between the actual and desired propulsive torques over a period, comparing the calculated torque difference to a first movement threshold, and when the calculated torque difference exceeds the first movement threshold, applying an electric parking brake (EPB) of the vehicle.

Presented are model-based control systems for operating parallel hybrid powertrains, methods for making/using such systems, and motor vehicles with parallel hybrid powertrains and model-based torque and speed control capabilities. A method for controlling operation of a hybrid powertrain includes receiving a command signal for a hybrid powertrain operation associated with a driver input and a current operating mode of the powertrain. A desired output torque for executing the powertrain operation is then determined. The method determines if a speed differential between an engine speed of an engine and a torque converter output speed of a torque converter is less than a calibrated threshold; if so, the method responsively engages a clutch device to operatively connect the engine's output member to the transmission's input member. Engine torque is then coordinated with motor torque such that the sum of the engine and motor torques is approximately equal to the desired output torque.

A vehicle propulsion system includes a transmission having manually selectable gear ratios, a manually operable clutch for selectively connecting the transmission to an engine for receiving torque from the engine and transmitting that torque through the transmission for propelling the vehicle, a clutch position sensor that generates a clutch position signal and a controller that is programmed to receive the clutch position signal, determine an actual engine output torque, determine an actual clutch torque capacity value based upon the actual engine output torque and the clutch position signal, determine a difference between the actual clutch torque capacity value and a clutch torque capacity from a torque to position table corresponding to the clutch position signal, determine an adjusted clutch torque capacity based upon the determined difference, and control an operation of the engine based upon the adjusted clutch torque capacity.

A derailleur-based electronic transmission system for an electric bicycle comprises a wheel; a driven sprocket set coupled to the wheel via at least a first one-way clutch, the driven sprocket set comprising two or more concentric sprockets of different effective diameters; a drive chain configured to engage the driven sprocket set; an electronically controllable derailleur configured to move the drive chain among the two or more sprockets; a pedal crank configured to cause rotation of the driven sprocket set by providing a user pedal force to the driven sprocket set through at least a second one-way clutch and the drive chain; a motor configured to cause rotation of the driven sprocket set by providing an electromechanical force to the driven sprocket set through at least a the drive chain; and an electronic controller configured to, responsive to a determination that a shift should occur at a time when neither the pedal crank nor the motor is causing rotation of the driven sprocket: operate the motor to rotate the driven sprocket at a rotational speed less than or equal to a current rotational speed of the wheel; and operate the derailleur to cause the shift to occur while the driven sprocket is being rotated by the motor.

In a hybrid vehicle, rotational speed control on a motor/generator connected to a first engagement clutch is carried out when there is a gear shift request to a gear shift stage at which the first engagement clutch of the multistage gear transmission is meshingly engaged. A transmission control unit is provided for outputting a meshing engagement instruction to the first engagement clutch when a rotational speed feedback control causes a differential rotation speed of the first engagement clutch to be within a range of a synchronization determination rotational speed. Upon executing the rotational speed feedback control on the motor/generator, this transmission control unit reduces the efficacy of the rotational speed feedback control less than before starting of the meshingly engagement, when the meshing engagement of the first engagement clutch is started.

A power transmission system of a vehicle and a gear-shift control method are provided. The power transmission system includes a first drive assembly (101) and a second drive assembly (102). The first drive assembly includes a first automatic transmission (2) and a first motor (1) connected with the first automatic transmission (2) for outputting power to two wheels of the vehicle. The second drive assembly (102) includes a second automatic transmission (2000) and a second motor (1000) connected with the second automatic transmission (2000) for outputting power to the other two wheels of the vehicle. The first and second automatic transmission are configured to be shifted to a preset gear or a gear adjacent to the preset gear, such that when one of the first and second automatic transmission is shifted to the preset gear, the other one of the first and second automatic transmission is shifted to the preset gear or the gear adjacent to the preset gear.

A launch control method for a continuously variable transmission (CVT) is provided, where the CVT comprises a hydro-mechanical variator, a summing transmission connected to an output side of the variator, and a clutch for selectively connecting the summing transmission to an output member. The method determines whether a launch has been requested, and adjusts a variable displacement pump of the variator to a predetermined fixed displacement. Engagement of the clutch is commenced, and the method then determines whether a predetermined degree of slip exists between input and output elements of the clutch. The clutch is held at its present state of engagement when the predetermined degree of slip has been established, and the variator is placed into a torque control mode. The method then determines when there is zero slip between the input and output elements of the clutch, and then instructs full engagement of the clutch. The method then holds the pump of the variator at its current displacement until a predetermined time period has elapsed, before reverting to a standard transmission control algorithm. A CVT is also provided.

A method for controlling an engine of a vehicle going downhill with a throttle operator in an idle position, and a driven pulley of a CVT initially having a driven pulley speed below a predetermined driven pulley speed, includes: determining a first speed, the first speed being proportional to the driven pulley speed; as the driven pulley speed increases and the driven pulley speed is below the predetermined driven pulley speed, increasing an actual engine speed as the driven pulley speed increases; the actual engine speed being an engagement speed when the driven pulley speed is the predetermined driven pulley speed; and as the driven pulley speed continues to increase and the driven pulley speed is above the predetermined driven pulley speed: controlling the engine to operate under conditions corresponding to an engine braking speed thereby causing engine braking, the engine braking speed being less than the actual engine speed.

A control device that includes an electronic control unit that causes a rotational speed of the rotating electric machine to change according to a predetermined first change pattern after the rotational speed of the rotating electric machine changes from a pre-shifting synchronous rotational speed in association with progress of the shifting operation until reaching a first synchronous range that is determined on the basis of a rotational speed of the internal combustion engine, the pre-shifting synchronous rotational speed being the rotational speed of the rotating electric machine in a shift speed established before the shifting operation is started.

A method for operating a drive train of a motor vehicle includes performing a startup operation of the motor vehicle or a stopping operation of the motor vehicle. A starting component (3) is engaged or bridged during the startup operation or the stopping operation of the motor vehicle. The startup operation is driven by a drive source (1). The method also includes comparing an actual value of an output shaft (22) based variable with a target value of the output shaft (22) based variable during the startup operation or the stopping operation and, on reaching or exceeding a specific deviation of the actual value from the target value, moving the starting component (3) into a slipping state. The starting component (3) transmits torque in the slipping state. A related drive train module for a motor vehicle is also provided.