Abstract: A vehicular transmission system (10) including a centrifugally operated master friction clutch (20) for drivingly coupling an engine (18) to an input shaft (28) of a mechanical transmission (12). Closed loop engine speed (ES) control is utilized to control engagement of the clutch during vehicle launch conditions.

Abstract: A control system/method for an at least partially automated transmission system (100) includes means to determine engine fueling required to cause a gross engine output torque (TEG (for zero flywheel torque)) resulting in zero flywheel torque (TFW=0). The engine (102) is caused to be fueled to the level required to cause zero flywheel torque at certain predetermined conditions, such as, for example, when disengaging a currently engaged ratio or during throttle recovery.

Abstract: A control system/method for an at least partially automated transmission system (100) includes means to determine engine fueling required to cause a gross engine output torque (TEG (for zero flywheel torque)) resulting in zero flywheel torque (TFW=0). The engine (102) is caused to be fueled to the level required to cause zero flywheel torque at certain predetermined conditions, such as, for example, when disengaging a currently engaged ratio or during throttle recovery.

Abstract: A vehicular centrifugally operated master friction clutch (20) for coupling an engine (18) to a transmission input shaft (28). The clutch includes flyweights (110) pivoted to a drving member (60) rotatable with the engine. Rollers (120) fixed to the flyweights act on ramp surfaces (148) to apply an axial clamping force (CF) to friction members of the clutch driving and driven member. The clamping force is applied through a spring compression (132) to limit the magnitude of clamping force.

Abstract: A control system/method controls a vehicular automated transmission system to modulate engagement of a centrifugal clutch. The automated transmission system including an internal combustion engine having an engine output member, a multiple speed change gear transmission having an input shaft, a centrifugal friction clutch for drivingly connecting said engine output member to said input shaft, a throttle responsive to manually requesting of a degree of engine fueling, and a system controller. The system controller has stored therein an engine speed limit used to facilitate vehicle launches.

Abstract: A control system/method for controlling a vehicle drivetrain (10) including an engine (18), a transmission (12) and, a centrifugal clutch (20) for drivingly coupling the engine output (136) to the transmission input shaft (28) during vehicle launch. A system controller (50) issues command output signals (56) for controlling engine speed (ES) on a closed loop basis.

Abstract: An integral gear life monitor system and method for determining gear use and damage is disclosed. The system includes a first and second sensors for measuring the rotational speed and torque of a driveline component, such as an input shaft of a vehicle transmission, for a particular gear ratio at one or more time intervals over a period of time. Each time interval may be in the range of 40 ms to 100 ms. The period of time may be hours, days, month, or even years. A processor performs a statistical summation technique to transform the signals from the first and second sensors into an equivalent amount time for the particular gear ratio during that period of time. A driveline vibration analyzer can perform an online determination of the torsional vibrations for the particular gear ratio to determine whether vibration is a root cause of why a gear ratio is worn or damaged.

Abstract: A vehicular transmission system (10) including a centrifugally operated master friction clutch (20) for drivingly coupling an engine (18) to an input shaft (28) of a mechanical transmission (12). Closed loop engine speed (ES) control is utilized to control engagement of the clutch during vehicle launch conditions.

Abstract: A method and system of controlling a maximum start gear ratio of an automated mechanical transmission system is disclosed. To protect the clutch under conditions of level ground up to a mild grade, a maximum starting gear is determined by the system when a valid Gross Combination Weight (GCW) of the vehicle is known. The maximum starting gear is defined as the highest starting gear ratio that will provide adequate startability without having to put excessive energy into the clutch during the start. The system will force a downshift if insufficient vehicle acceleration is detected by the system. If the GCW of the vehicle is not known, the maximum start gear will be limited to that for a fully laden vehicle. To protect against too much power being transmitted through the clutch, the power through the clutch is determined and the engine torque and/or engine speed is limited to values resulting in power through the clutch below a preset value.

Abstract: A control system/method for an at least partially automated transmission system (100) includes means to determine engine fueling required to cause a gross engine output torque (TEG (for zero flywheel torque)) resulting in zero flywheel torque (TFW=0). The engine (102) is caused to be fueled to the level required to cause zero flywheel torque at certain predetermined conditions, such as, for example, when disengaging a currently engaged ratio or during throttle recovery.

Abstract: 3A method/system for controlling upshifting in an automated mechanical transmission system (10) utilized on a vehicle preferably having an ECU (28) controlled engine brake (ECB) or inertia brake (26). When an upshift from a currently engaged ratio (GR) is required (ES>ESU/S), skip upshifts (GRTARGET=GR+N, N>1) and then single upshifts (GRTARGET=GR+1) are evaluated in sequence.

Abstract: A system and method for decreasing the time required to complete a ratio change in an electronically enhanced powertrain system include independently controlling at least one engine-side retarding device and at least one transmission-side retarding device. The retarding devices are selectively actuated to increase the decay rate of the engine speed and/or transmission input shaft speed during an upshift. Engine-side retarding devices may include an engine brake or operation of various engine accessories to increase engine loading. Transmission-side retarding devices may include input shaft brake or driveline retarder.

Abstract: A system/method of resetting the value of a control parameter (GCWCP) indicative of vehicular gross combined weight and determined as a filtered/averaged value, to a predetermined default value upon sensing vehicle operating conditions (50% GCWCP<GCWTEST or 200% GCWCP>GCWTEST)deemed indicative of a change in vehicle loading. A vehicle automated system, such as an automated mechanical transmission system, is controlled as a function of the value of the control parameter.

Abstract: A control system/method to initiate upshifts in an automated mechanical transmission system (12). Upshifts are normally initiated on the basis of sensed throttle position (THL) or demand. In certain situation upshifts are initiated on the basis of sensed or calculated engine torque.

Abstract: A method/system for controlling upshifting in an automated mechanical transmission system (10) utilized on a vehicle preferably having an ECU (28) controlled engine brake (46). When an upshift from a currently engaged ratio (GR) is required (ES>ESU/S), skip upshifts (GRTARGET=GR+N, N>1) and then single upshifts (GRTARGET=GR+1) are evaluated in sequence.

Abstract: A method/system for controlling an automated mechanical transmission system (10) utilized on a vehicle. To protect from driveline damage due to clutch "popping," upon sensing vehicle launch conditions (clutch (16) not engaged, transmission (14) engaged (THL>REF.sub.THL and OS<REF.sub.SPEED)), engine speed is limited to idle speed plus a preset value (ES<(ES.sub.IDLE +RPM)).

Abstract: A system/method of resetting the value of a control parameter (GCW.sub.CP) indicative of vehicular gross combined weight and determined as a filtered/averaged value, to a predetermined default value upon sensing vehicle operating conditions deemed indicative of a change in vehicle loading. A vehicle automated mechanical transmission system is controlled as a function of the value of the control parameter. The default value is relatively high compared to the expected range of actual vehicle gross combined weight. Large skip upshifts, greater than 50% ratio step, are prohibited after a reset until the control parameter value is verified.

Abstract: A control for enhanced manual shifting in a computer-assisted (48) vehicular splitter-type compound transmission (16) having a synchronized main section (16A) shifted by a manually operated shift lever (31) and a controller (42). The splitter section (16B) is located at the input end of the transmission, is provided with a three-position (L, H, N) actuator (46), and is commanded to a splitter-neutral position upon sensing an intent for a main section shift to neutral and remains in splitter neutral until the main section is reengaged to reduce the forces required to synchronize the main section.

Abstract: A control for enhanced manual shifting in a computer-assisted (48) vehicular splitter-type compound transmission (16) having a synchronized main section (16A) shifted by a manually operated shift lever (31) and a controller (42). The splitter section (16E) is provided with a three-position (L, H, N) actuator (46) and is commanded to a splitter-neutral position upon sensing a main section shift to neutral to reduce the forces required to synchronize the main section.

Abstract: A control for enhanced manual shifting in a computer-assisted (48) vehicular splitter-type compound transmission (16) having a synchronized main section (16A) shifted by a manually operated shift lever (31) and a controller (42). The splitter section (16B) is located behind the main section and is provided with a three-position (L, H, N) actuator (46) and is commanded to a splitter-neutral position upon sensing an intent for a main section shift to neutral and remains in splitter neutral until the main section is reengaged to reduce the forces required to synchronize the main section.