A method of estimating a load on a vehicle (10), the method comprising: obtaining a first load estimate using a first load estimation technique; obtaining a second load estimate using a second load estimation technique; analysing characteristics of the first load estimate and the second load estimate; and, based on the analysis selecting either the first load estimate or the second load estimate as an output load estimate.

A transmission includes an input shaft and an output shaft, the input shaft selectively accepting a torque input from a prime mover, and the output shaft selectively providing torque output to a driveline. A controller determines a shaft displacement angle representing an angle value of rotational displacement difference between at least two shafts of the transmission, and performs a transmission operation responsive to the shaft displacement angle.

A method and system for controlling clutch friction elements of an automatic transmission is provided. The method includes retrieving information about shift clutches from a data storage unit and acquiring information required to predict a temperature of a friction element for each shift clutch, deriving a predicted temperature value of a friction element for each shift clutch by using the information about the shift clutches and the information required to predict the temperature of the friction element, predicting whether or not overheating occurs for each shift clutch by comparing the derived predicted temperature value of the friction element for each shift clutch with an allowable temperature set for each shift clutch, and determining a target shift stage while avoiding the overheating clutch with a predicted temperature value exceeding the allowable temperature, through switching to an avoidance shift mode.

Systems and methods for operating a driveline disconnect clutch of a hybrid vehicle are presented. In one example, a driveline disconnect clutch pressure is measured just prior to a request to close the driveline disconnect clutch and a time duration for driveline disconnect clutch boost pressure is adjusted in response to the measured driveline disconnect clutch pressure.

Systems and methods for operating a hybrid powertrain that includes an engine and a motor/generator are described. The systems and methods adjust torque converter clutch opening responsive to whether or not a motor/generator is available to provide a negative torque to a driveline. Further, the motor/generator and the vehicle's engine are operated to provide a desired amount of driveline braking.

The drive system from the engine (1) to the drive wheels (7) of a vehicle is equipped with a torque converter (2), which has a lock-up clutch (3), and a variator (4). Said engined car is provided with a lock-up control means for controlling the engagement/disengagement of the lock-up clutch (3) and a gear change mode switch-controlling means (FIG. 8) for performing control to switch between a “continuously variable gear change mode” and a “DSTEP gear change mode.” While traveling, the gear change mode switch-controlling means (FIG. 8) prohibits gear change by the “DSTEP gear change mode” when the detected oil temperature is at or below a lock-up engagement-permitting threshold for permitting engagement of the lock-up clutch (3) and allows gear change by the “DSTEP gear change mode” when the detected oil temperature is higher than the lock-up engagement-permitting threshold.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. A shift actuator selectively couples the input shaft to the main shaft by rotatably coupling gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. An integrated actuator housing includes a single external power access for the shift actuator. A controller interprets a shaft displacement angle, determines if the transmission is in an imminent zero or zero torque region, and performs a transmission operation in response to the transmission in the imminent zero or zero torque region.

A transmission includes an input shaft coupled to a prime mover, a countershaft, main shaft, and an output shaft, with gears between the countershaft and the main shaft. The shift actuator is mounted on an exterior wall of a housing including the countershaft and the main shaft. A shift control circuit operates a shift actuator using a first opposing pulse command and a first actuating pulse command, and releases pressure with shift actuating and opposing volumes of the shift actuator upon determining a shift completion event.

A control device for an automatic transmission includes: a failure diagnosis section for diagnosing whether or not a failure has occurred in a shift control system of the automatic transmission; a fail-safe control section for fixing the automatic transmission into a predetermined gear position in response to confirmation of the failure of the shift control system of the automatic transmission; and an oil temperature rise regulation torque reduction control section for outputting a torque reduction request to suppress torque of a vehicle driving source, based on temperature of transmission operating oil of the automatic transmission, and outputting the torque reduction request in response to satisfaction of an oil temperature condition that is set lower in oil temperature when the automatic transmission is fixed in a first gear position by the fail-safe control section than when the automatic transmission is not fixed in the first gear position.

A driving system includes an engine an engine, a motor generator, a gear mechanism, and a controller. The gear mechanism couples the engine and the motor generator to each other. The gear mechanism includes first and second gears. The first and second gears are configured to be supplied with first driving torque from the engine and second driving torque from the motor generator, respectively. The second gear meshes with the first gear. The controller is configured to perform torque control of the engine to make a rate of variation in the first driving torque at the first gear at a time when the following conditional expression (1) is satisfied smaller than that at a time when the following conditional expression (1) is not satisfied.
|T2−T1|<Th1  (1) T1 is the first driving torque, T2 is the second driving torque, and Th1 is a first threshold.