Abstract: A transmission includes sensors positioned adjacent respective pairs of magnetized bands on a shaft of the transmission for detecting magnetic flux emanating from the bands in response to torque on the shaft. The transmission further includes an electronics interface assembly configured to respectively provide drive signals to the sensors and to receive from the sensors, in response to the drive signals, output signals indicative of the torque on the shaft as detected by the sensors.

Abstract: Designs to package a magneto-elastic torque sensor in an automotive transmission for volume production applications are provided. A transfer case assembly includes a transfer case shaft having a magnetized region and a magnetic torque sensor, for detecting torque of the transfer case shaft, mounted on at least one bushing supporting the transfer case shaft. A drive axle assembly includes an axle housing, an input shaft having a magnetized region, and a magnetic torque sensor, for detecting torque of the input shaft, mounted to the axle housing.

Abstract: A powertrain includes an engine, a transmission, and one or more accessories, such as an alternator or an air conditioning compressor, all operating based on commands from a controller. The controller is programmed to coordinate commands to the transmission with commands to the accessories to mitigate the impacts of transmission state changes. The accessory drive torque may be adjusted to compensate for the torque required to change the speed of a transmission internal shaft. The accessory effective inertia may be adjusted to maintain a powertrain natural frequency so that active damping can be maintained throughout a transmission state change event.

Abstract: A transmission clutch control method includes defining a transfer function relating clutch torque to a control signal under transmission operating conditions; determining a target clutch torque for current operating conditions; determining the target control signal from the transfer function to produce target torque at the clutch; correcting clutch torque on the basis of a difference between the target clutch torque and the actual torque at the clutch by adjusting the control signal; calculating actual clutch torque with reference to transmission input torque and transmission output torque; computing a clutch torque error as a difference between calculated clutch torque and the target clutch torque; and repetitively adjusting the transfer function on the basis of the clutch torque error.

Abstract: During state transitions, a clutch actuator position command includes an oscillating component called a dither. This dithering helps avoid jumps in the actuator position due to friction when the commanded position is changed gradually. Also, dither during a transition from fully released to slipping causes the natural frequency of the system to change gradually rather than abruptly. This permits use of another slipping clutch for active damping based on a measured oscillation.

Abstract: A method of controlling a line pressure in a transmission is provided. Line pressure in a transmission is set to a pressure value including a first term that is proportional to an input torque value. The first term has a coefficient of proportionality that is increased in response to a signal indicating clutch slippage. The input torque value is a measured input torque value in a steady-state condition. The input torque value may be a maximum of the measured input torque value and a driver demand torque value in a transient condition.

Abstract: A method of operating a vehicle includes measuring a transmission output torque, measuring impeller and turbine speeds, estimating a transmission component torque, and adjusting an engine torque to avoid overstressing a transmission component such as a gear. The method does not rely on an accurate estimate of engine torque. Furthermore, the method does not rely on a fixed transmission torque rating in each gear ratio.

Abstract: A transmission calibration tool automatically generates a detailed gearbox model based on a user input transmission topology description. During transmission calibration, the tool accepts inputs from transmission speed and torque sensors and estimates component torques for each gear element and each shift element. Following a shift or other transmission event, the calibration tool plots the component torques as a function of time, permitting the calibration engineer to better understand what is occurring during the event, and thus reducing the time required for calibration. The calibration tool also adapts several transmission component models and outputs the adapted models to provide insight into actual transmission component behavior.

Abstract: A method of operating a transmission includes measuring an output torque, estimating a gearbox input torque using a model, and estimating gearbox component torques based on a detailed gearbox model. The model used to estimate the input torque varies depending on whether a torque converter is locked, open, or slipping. In some operating conditions, multiple estimates are available for gearbox input torque, impeller torque, or shift element torque in which case the models are adapted. When an estimated component torque is outside an expected range, a warning flag is raised and diagnostic data is saved. When an estimated torque approaches or exceeds a torque limit, the input torque command may be reduced to prevent component damage. A warning flag may also be raised and diagnostic data saved in response to a model parameter being adapted to a value outside of a predetermined range.

Abstract: A transmission and control method are disclosed which ensure proper stroke pressure and minimize torque transients during a shift event. The transmission includes a clutch having a torque capacity based on a fluid pressure, a torque sensor adapted to measure a torque value that varies in relationship to the torque capacity, and a controller. The method includes varying the fluid pressure around a predetermined value, measuring a resulting torque difference with the torque sensor, and adjusting a clutch control parameter if the resulting torque difference is less than a threshold value.

Abstract: A method of downshifting an automotive transmission. An on-coming transmission element is stroked while pressure for an off-going element is reduced. Pressure for the stroked on-coming element is increased to be sufficient to carry torque. Pressure for the off-going element is reduced below a torque transmitting amount once the stroked on-coming element has a sufficient torque carrying capacity. Torque capacities for the elements are determined from transmission output torque and acceleration and transmission input torque and acceleration. Feed forward or feedback terms for off-going and on-coming element torque capacities may be calculated using the transmission output torque, transmission input acceleration, and transmission input torque.

Abstract: Designs to package a magneto-elastic torque sensor in an automotive transmission, such as front wheel drive (FWD) automatic transmissions, for volume production applications are provided.

Abstract: A vehicle powertrain includes a transmission and a clutch. The slip of the clutch is adjusted to a predefined target where a sensed parameter of a shaft of the transmission corresponds to a specified noise, vibration, and harshness (NVH) level in the powertrain. The sensed parameter of the transmission shaft may be one of acceleration, speed, and torque of the transmission shaft. The transmission shaft may be one of the input shaft and output shaft of the transmission.

Abstract: A transmission and control method are disclosed which ensure proper stroke pressure and minimize torque transients during a shift event. The transmission includes a clutch having a torque capacity based on a fluid pressure, a torque sensor adapted to measure a torque value that varies in relationship to the torque capacity, and a controller. The method includes varying the fluid pressure around a predetermined value, measuring a resulting torque difference with the torque sensor, and adjusting a clutch control parameter if the resulting torque difference is less than a threshold value.

Abstract: Designs to package a magneto-elastic torque sensor in an automotive transmission for volume production applications are provided. A transfer case assembly includes a transfer case shaft having a magnetized region and a magnetic torque sensor, for detecting torque of the transfer case shaft, mounted on at least one bushing supporting the transfer case shaft. A drive axle assembly includes an axle housing, an input shaft having a magnetized region, and a magnetic torque sensor, for detecting torque of the input shaft, mounted to the axle housing.

Abstract: Designs to package a magneto-elastic torque sensor in an automotive transmission for volume production applications are provided. One transmission includes an output shaft and a magnetic torque sensor. The output shaft has a magnetized region. The sensor, for detecting torque of the output shaft, is mounted on friction reduction members such as bushings supporting the output shaft. In another transmission, the sensor is alternatively mounted to a transmission case.

Abstract: A method for controlling a manual transmission includes using a controller to determine a desired torque transmitted through an input clutch for the desired gear after a shift lever is moved to a desired gear position and while a clutch pedal is being released for engaging the clutch; inferring torque in the vehicle drive assembly; using inferred torque to determine clutch torque; and using the controller to automatically adjust a clutch actuator such that a difference between the desired torque and the inferred torque is reduced.

Abstract: A method for controlling a manual transmission includes using a controller to determine a desired torque transmitted through an input clutch and a desired clutch slip for the desired gear after a shift lever is moved to a desired gear position and while a clutch pedal is being released for engaging the clutch; measuring torque in the vehicle drive assembly; using measured torque to determine actual clutch torque transmitted through the clutch; and reducing torque error using the controller to adjust a clutch actuator such that a difference between the desired torque and the actual torque is reduced. Slip error may also be reduced by adjusting the clutch actuator to reduce the difference between the desired slip and measured slip.

Abstract: A method of downshifting an automotive transmission. An on-coming transmission element is stroked while pressure for an off-going element is reduced. Pressure for the stroked on-coming element is increased to be sufficient to carry torque. Pressure for the off-going element is reduced below a torque transmitting amount once the stroked on-coming element has a sufficient torque carrying capacity. Torque capacities for the elements are determined from transmission output torque and acceleration and transmission input torque and acceleration. Feed forward or feedback terms for off-going and on-coming element torque capacities may be calculated using the transmission output torque, transmission input acceleration, and transmission input torque.

Abstract: A torque sensor assembly is used to measure torque in a powertrain of a motor vehicle, the powertrain including a power source and a transmission. A sensor is coupled to an oil seal housing, which is coupled to the engine. Each of the sensor and the oil seal housing has a mounting hole formed therein. The sensor is coupled to the oil seal housing, and the oil seal housing to the engine, by inserting one fastener into both mounting holes. The sensor measures an amount of torque exerted on a drive plate of the transmission. The drive plate includes a central disk, made of a magnetizable material, and an outer ring coupled to the central disk. The sensor is a magnetic torque sensor, which determines an amount of torque exerted on the central disk of the drive plate by sensing a magnetic flux passing through the drive plate.