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 for preventing damage to a vehicular driveline (10) during attempts to launch a vehicle from a stopped condition while engaged in an inappropriate start ratio. The control involves sensing engaged transmission ratio (GR) and vehicle speed (OS) to determine if the vehicle is being launched while the transmission is engaged in an inappropriate start ratio and, if such conditions are sensed, issuing command signals to the engine controller (36) to cause engine output torque to be limited to a predetermined value, preferably a value less than 50% of maximum engine output torque.

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 control system/method to minimize unwanted upshifts in an automated mechanical transmission system (12). Upshifts are prohibited unless throttle position (THL) has achieved a substantially steady-state value (.vertline.(d/dt(THL)).vertline.<REF-1) or a speed value (ES, IS, OS) exceeds a reference (OS<REF-2).

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 downshifting in an automated mechanical transmission system (10) utilized on a vehicle. When a downshift from a currently engaged ratio (GR) is required (ES<ES.sub.D/S), skip downshifts (GR.sub.TARGET =GR-N, N>1) and then single downshifts (GR.sub.TARGET =GR-1) are evaluated in sequence. If throttle demand is high (THL>REF), skip downshifts are evaluated to determine if they can be completed at no greater than a reference value (ES.sub.DES =ES.sub.DES-DEFAULT +offset), which is higher than otherwise (ES=ES.sub.DES-DEFAULT) allowed.

Abstract: A control for enhanced manual start ratio engagement in a computer-assisted (48) vehicular compound transmission (16) having a synchronized main section (16A) shifted by a manually operated shift lever (31), an auxiliary splitter section, and a controller (48). The splitter section (16E) 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 that the vehicle is essentially stopped (OS<REF), that the master clutch (14) is disengaged and the main section is in neutral.

Abstract: A diagnostic driveline vibration analyzing tool for measuring and characterizing the torsional vibrations in a vehicle driveline. An electronic control unit and sensor cooperate to measure speed fluctuations occurring between the passing of adjacent teeth of a rotating gear. These time measurements are the basis for displacement, velocity and acceleration calculations which, combined with driveshaft rotational order information, can be used to pinpoint the source of excessive driveline torsional vibrations.

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 method/system for controlling downshifting in an automated mechanical transmission system (10) utilized on a vehicle. The anti-hunt logic after an upshift will sense conditions of high throttle demand (THL>85%) and low vehicle acceleration (d/dt(OS)<0) and reduce at least a portion (72) of the direction of last shift anti-hunt offset to the downshift profiles.

Abstract: A control system/method for controlling inertia brake (19) operation in an automated mechanical transmission system (10) shifted without disengaging the master clutch (16). A value representing inertia brake temperature (T.sub.SIM) is simulated and compared to reference values to determine if inertia brake operation is allowable.

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 method/system for controlling upshifting in an automated mechanical transmission system (10) utilized on a vehicle. 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. If throttle demand is high (THL>REF), to encourage performance-oriented selection of ratios, skip upshifts are evaluated to determine if they can be completed at a higher engine speed (ESMIN=ESDEFAULT+offset) than is otherwise required.

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 pin-type, double-acting synchronizer and gear assembly (10) with friction rings (26, 46 and 28, 48), jaw members (30, 38 and 32, 40) axially secured together by retainers (44), three circumferentially spaced pins (50) including blocker shoulders for preventing asynchronous engagement of the jaw clutches, and pre-energizer assemblies (52) to ensure initial engagement of the friction rings and blocker shoulders in response to initial engaging movement of a shift flange (42), and self-energizing ramps (20a-20d and 62a-62d). The assembly (10) includes improved jaw members and self energizing ramps, an improved shift flange, improved pre-energizers, and improved jaw member retainers. A second synchronizer and gear assembly embodiment (110) includes the above improvements plus an over stress reduction of splines 112g, 140 when gear 116 is connected to shaft 112.

Abstract: A control system and method for an automated mechanical transmission system (10) including an engine braking mechanism (14A) is provided for allowing operator request for an automatic direct downshift into the selected ratio (GR.sub.EB) automatically determined to provide optimum engine braking under current vehicle operating conditions. Retaining the control lever (1) in a displaced position for longer than a reference period of time (REF), such as one or two seconds, while the engine brake is active, will initiate the automatic determination and shift into the selected ratio (GR.sub.EB) determined to provide optimum engine braking under current vehicle operating conditions procedure.

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.

Abstract: A mechanical transmission (14) having a plurality of ratios (first-twelfth) and an automated system (10) utilizing same, has an upper group of ratios (seventh-twelfth) having a relatively small average ratio step (13%) compared to the average ratio steps (30%-40%) of comparable transmissions. This allows high-speed operation (35-70 mph) at or very nearing desired engine speed (112), emulating the characteristics of a CVT.

Abstract: A powertrain system (10) control system/method for controlling engine (12) output torque as a function of sensed degree of engagement of jaw clutch members (62, 64) associated with the engaged ratio of a transmission (14).