WO2015183937A1

WO2015183937A1 - Heavy-duty engine speed synchronization for manual transmissions

Info

Publication number: WO2015183937A1
Application number: PCT/US2015/032650
Authority: WO
Inventors: Jonathan A. DICKSON; Gary E. ECKERT; Peter A. BRITANYAK
Original assignee: Cummins, Inc.
Priority date: 2014-05-30
Filing date: 2015-05-27
Publication date: 2015-12-03
Also published as: CN106461071A; CN106461071B

Abstract

A method includes detecting a shift event out of a first gear of a manual transmission based on at least one of speed, acceleration, and torque of an engine. The engine and the transmission comprise a powertrain system of a vehicle. The first gear is determined based on each of engine speed and vehicle speed prior to the shift event. A desired gear is predicted based on the first gear and at least one of engine speed, vehicle speed, and vehicle acceleration. Transmission input speed for the desired gear is determined based on each of the engine speed and the vehicle speed. Engine speed is controlled to synchronize the engine speed with the transmission input speed for the desired gear.

Description

HEAVY-DUTY ENGINE SPEED SYNCHRONIZATION FOR

MANUAL TRANSMISSIONS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 62/005,512, filed May 30, 2014, which is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] The present disclosure relates to a powertrain system for a vehicle. More particularly, the present disclosure relates to systems and methods for controlling engine speed synchronization.

BACKGROUND

[0003] Manual transmissions are typically shifted from one gear to another by depressing a clutch pedal to disengage the engine from the transmission while a gearshift operation takes place. When shifting between gears, it is necessary to synchronize the engine speed with the transmission engaging element speed. Shifting to a higher gear, or "upshifting," requires lower engine speeds and shifting to a lower gear, or "downshifting," requires higher engine speeds. Typically, to shift to a higher gear, the clutch is depressed and the engine is allowed to slow down (e.g., due to friction, drag, grade, etc.) until its speed matches that of the transmission engaging element for the next gear. To shift to a lower gear, the clutch is depressed and the throttle is used to speed up the engine until its speed matches that of the transmission engaging element for the next gear.

SUMMARY

[0004] One embodiment relates to a method including detecting a shift event out of a first gear of a manual transmission based on at least one of speed, acceleration, and torque of an engine. The engine and the transmission comprise a powertrain system of a vehicle. The first gear is determined based on each of engine speed and vehicle speed prior to the shift event. A desired gear is predicted based on the first gear and at least one of engine speed, vehicle speed, and vehicle acceleration. Transmission input speed for the desired gear is determined based on each of the engine speed and the vehicle speed. Engine speed is controlled to synchronize the engine speed with the transmission input speed for the desired gear.

[0005] Another embodiment relates to a system including a powertrain system of a vehicle. The powertrain system includes an engine and a manual transmission. The system also includes a controller in operative communication with the powertrain system. The controller is structured detect a shift event out of a first gear of the transmission based on at least one of speed, acceleration, and torque of the engine. The engine is operably coupled to the manual transmission. The first gear is determined based on each of engine speed and vehicle speed prior to the shift event. A desired gear is predicted based on the first gear and at least one of engine speed, vehicle speed, and vehicle acceleration.

Transmission input speed for the desired gear is determined based on each of the engine speed and the vehicle speed. Engine speed is controlled to synchronize the engine speed with the transmission input speed for the desired gear.

[0006] Still another embodiment relates to a controller in operative communication with a powertrain system of a vehicle. The controller is structured to detect an out-of-gear shift event based on detecting each of a decoupling of engine speed and transmission output speed, and a reduction in torque output from an engine. The powertrain system includes the engine and the transmission. A desired gear is predicted based at least in part on a prior gear and at least one of engine speed, vehicle speed, and vehicle acceleration. The transmission input speed for the desired gear is determined based on each of the engine speed and the vehicle speed. Engine speed is controlled to synchronize the engine speed with the transmission input speed for the desired gear.

[0007] These and other features, together with the organization and manner of operation thereof, will become apparent from the following detailed description when taken in conjunction with the accompanying drawings, wherein like elements have like numerals throughout the several drawings described below.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Fig. 1 is a schematic diagram of a speed synchronization system, according to an embodiment. [0009] Fig. 2 is a block diagram illustrating the function and structure of the controller of the speed synchronization system of Fig. 1, according to an embodiment.

[0010] Fig. 3 is a gearshift plot of engine speed versus vehicle speed for a vehicle including a manual transmission.

[0011] Fig. 4 is a flow diagram of a method of synchronizing engine speed with transmission speed, according to an embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Manual transmissions for passenger cars and light trucks are conventionally mechanically synchronized. For example, synchronized manual transmissions (e.g., "Synchromesh transmissions") typically utilize a locking synchronizer assembly, which utilizes friction between a synchronizer ring and a clutch body attached to the gear to equalize rotational speed. The synchronizer ring prevents engagement until the speeds are synchronized.

[0013] However, transmissions for commercial vehicles, such as heavy trucks and machinery, are not typically synchronized. Reliability is paramount for commercial vehicle transmissions and engines, as they are designed to operate for much longer compared to passenger cars and light trucks. For example, commercial vehicles may be designed to run for 1,000,000 miles, whereas passenger cars may be designed to run for 300,000 miles. Mechanical synchronizer assemblies are not suitable for significantly long operation (e.g., greater than 300,000 miles) because the friction material (e.g., brass) in synchronizers is more prone to wear and breakage than gear material (e.g., forged steel). In addition, mechanical synchronizers add additional complexity that may degrade reliability and increase cost. Accordingly, operators of commercial vehicles must manually synchronize engine speed when shifting.

[0014] Speed synchronization when upshifting is typically not a problem because the engine speed naturally decreases when the throttle is not engaged due to friction, drag, grade, etc. Accordingly, the engine speed naturally tends to slow down to loosely match the lower speed of the higher gear. However, when downshifting, the engine needs to speed up to match the higher speed of the lower gear. If the accelerator is not "blipped" (e.g., briefly and quickly pressed to speed up the disengaged engine), the difference between the engine speed and the transmission input shaft speed is abruptly synchronized when the clutch is engaged. The abrupt synchronization often causes a sudden deceleration of the vehicle, which may be described as a "lurch" or "jolt." This also causes increased wear on vehicle components (e.g., gears, clutch, etc.). Therefore, a staple of advanced or professional manual-transmission driving is the "rev match", or "throttle blip", in which the driver quickly brings the engine up to speed while downshifting by use of the throttle.

[0015] Various embodiments relate to systems and methods for controlling engine speed synchronization. According to an embodiment, a controller is operatively coupled to a powertrain system, including an engine and a transmission. The controller is structured to detect a shift event out of a first gear. The shift event may be detected based on at least one of speed, acceleration, and torque of the engine. In some embodiments, the shift event is not detected based on a signal indicating any of shift lever operation, clutch pedal engagement, and clutch engagement. For example, in one embodiment, the shift event is detected based on a detected decoupling of engine speed and transmission output speed. The first gear and the desired gear are determined by cross-referencing engine speed and vehicle speed prior to the shift event. The transmission input speed for the desired gear is determined, and the controller operates to control the engine speed to synchronize the engine speed with the transmission input speed for the desired gear.

[0016] The engine speed synchronization system, according to various embodiments, provides improved operation of powertrain systems including engines and manual transmissions. In some embodiments, the speed synchronization system can be

implemented with currently produced hardware and retrofitted on existing vehicles.

Furthermore, the speed synchronization system may be retrofitted without requiring additional sensors to be installed. Specifically, the speed synchronization system may be implemented without requiring sensors to indicate the operation of a shift selector or other sensors associated with the transmission. Thus, the speed synchronization system may be implemented for certain vehicles that do not utilize electronic transmission control systems.

[0017] The engine speed synchronization system also makes engines easier to control during manual transmission shift events. This will help inexperienced operators become proficient more quickly, thereby providing a comparative advantage over conventional powertrain systems. In addition, the engine speed synchronization system will increase the lifespan of trucks, engines, and transmissions by optimizing shift events, thereby decreasing transmission gear wear and engine transients.

[0018] The engine speed synchronization system also enables improved fuel economy in various ways. First, the speed synchronization system improves fuel economy by providing a means for reduced engine speed during downshift events via variable ratio steps in the transmission. Conventionally, all ratios steps are set consistently to make achieving synchronization easier for the driver. Second, the speed synchronization system improves fuel economy by providing faster shift times, which can result in an opportunity to reduce lost turbocharger energy and reduced speed loss during shifts. This provides the engine an opportunity to produce less power but have similar vehicle acceleration capability relative to an engine without this feature. Third, the speed synchronization system improves fuel economy by enabling a neutral coasting strategy for manual transmissions, which has been proven to save fuel via reductions to engine motoring losses. Fourth, the speed synchronization system improves fuel economy by enabling vehicle efficiency gains via more aggressive downspeeding due to improvements to shifting ease.

[0019] Fig. 1 is a schematic diagram of a speed synchronization system 100, according to an embodiment. The speed synchronization system includes a controller 102 in operative communication with a powertrain system 104 of a vehicle (not shown). The vehicle may be an on-road or off-road vehicle including, but not limited to, line-haul trucks, mid-range trucks (e.g., pick-up trucks), tanks, airplanes, and any other type of vehicle that utilizes a transmission.

[0020] In general, the powertrain system 104 facilitates power transfer from an engine 106 to power the vehicle. As shown in Fig. 1 , the powertrain system 104 includes the engine 106 operatively coupled to a transmission 108. More specifically, a crankshaft 110 of the engine 106 is selectively coupled to an input shaft 112 of the transmission 108 via a clutch 114. The clutch 114 may be selectively engaged and disengaged via a clutch pedal 116. The transmission 108 may include one or more gear trains or gear sets. The gear trains may have one or more fixed or variable gear ratios. The engine 106 may be an internal combustion engine, such as a compression-ignition (e.g., diesel-powered) engine or a spark-ignition (e.g., gasoline-powered) engine. In other embodiments, the powertrain system 108 may include a hybrid drive system, a full electric drive system, or other powertrain systems.

[0021] The powertrain system 104 also includes a drive shaft 118 operatively coupling the transmission 108 and a differential 120. The differential 120 includes a set of gears configured to transmit rotational energy from the drive shaft to the axle 122 to power the final drive 124 (e.g., wheels, tracks, etc.). The final dive 124 propels the vehicle. In the embodiment illustrated in Fig. 1, the transmission 108 is a manual transmission in which the operator selects an operating gear of the transmission via a shift selector 126. The powertrain system 104 further includes a plurality of sensors 128 in operative

communication with the components of the system 100. For example, the sensors 128 may include speed sensors, torque sensors, grade sensors, etc. In some embodiments, the powertrain system 104 includes an operator I/O interface 130. The operator I/O interface 130 may include a display and an input device by which the operator may receive information related to operating conditions of the vehicle, and execute commands based on the received information. For example, the operator I/O interface 130 may be configured to display the desired gear that is determined by the controller 102.

[0022] As mentioned briefly above, the clutch 114 selectively couples the engine 106 and the transmission 108 by way of operation of the clutch pedal 124. In other

embodiments, the clutch 114 may be an automatic clutch that is automatically engaged and disengaged via a clutch servo. When the clutch 114 is engaged (e.g., "in gear"), there is a mechanical connection between the engine 106 and the final drive 122, which keep them in sync with each other. When shifting, however, the clutch pedal 124 must be depressed to disengage the clutch 114. This breaks the mechanical connection between the engine 106 and the final drive 124, and the speed of the engine 106 is no longer linked to that of the final drive 124. After shifting to a new gear, it is necessary to synchronize the speed of the engine 106 with the speed of the transmission input shaft 112 (e.g., the transmission engaging element) of the new gear.

[0023] The typical sequence for accelerating a vehicle (e.g., a diesel truck) from a stop for conventional vehicles that do not include the speed synchronization system 100 is as follows. First, when the vehicle is stationary and the engine 106 is idling (e.g., zero vehicle speed), the clutch pedal 116 is depressed to disengage the clutch 114 and a desired launch gear (e.g., first or second gear) is selected. Next, the clutch pedal 116 is slowly released until the clutch 114 is fully engaged without depressing the accelerator pedal (e.g., 0% accelerator pedal). The accelerator pedal is increasingly depressed until engine speed reaches approximately 1500 revolutions per minute (RPM). The operator then shifts into neutral by applying a small force on the shift selector 126 (e.g., shift lever) of the transmission 108 while lifting on the throttle pedal, thereby pulling out of gear as the engine 106 crosses "zero torque." The shift selector 126 is then moved to the "neutral" position. The operator then typically waits for the engine 106 to decelerate to the appropriate speed for the next gear. When the appropriate speed is met, the operator moves the shift selector 106 to the next desired gear.

[0024] Certain conventional transmissions may have a gear ratio step size of 35%, for example. If the operator chooses the shift speed to be 1500 RPM, then the synchronous speed for upshifting to the next gear would be 1110 RPM. While in neutral, the vehicle typically tends to decelerate due to friction and drag, among other things. The synchronous speed changes along with vehicle speed.

[0025] Shifting into a gear when the engine 106 speed is not synchronized for that gear is undesirable for numerous reasons. First, if the engine 106 speed and the transmission 108 input speed are not close enough to a match, gear engagement is not possible. If the speeds are close enough for engagement but not matched, the gear can be engaged, but may cause the engine 106 to jump as the gears force the engine 106 speed to the vehicle 106 speed. In addition, non-synchronized engagement may cause strain on the clutch 114, gears, powertrain 104, driver, passengers, cargo, etc. Synchronizing the correct speed takes significant experience and practice. For example, speed synchronization may involve increasing the accelerator percentage to increase vehicle speed to match the new gear. This must be repeated for each new gear, which may be difficult to master.

[0026] As shown in Fig. 1, the controller 102 is communicably coupled to the powertrain system 104. Communication between and among the components may be via any number of wired or wireless connections. For example, a wired connection may include a serial cable, a fiber optic cable, a CAT5 cable, or any other form of wired connection. In comparison, a wireless connection may include the Internet, Wi-Fi, cellular, radio, etc. In one embodiment, a controller area network ("CAN") bus provides the exchange of signals, information, and/or data. The CAN bus includes any number of wired and wireless connections. Because the controller 102 is communicably coupled to the systems and components in the powertrain system 104, the controller 102 is structured to receive data from one or more of the components shown in Fig. 1. The vehicle operating data may be received via one or more sensors (e.g., a speed sensor attached to the engine 106) attached to the components in Fig. 1. As described more fully herein, due to the integration of the controller 102 with the components of Fig. 1, the controller 102 can acquire this data to dynamically adjust the speed of the engine 106 to substantially achieve various operating characteristics of one or more vehicle operating parameters.

[0027] As the components of Fig. 1 are shown to be embodied in a system 100, the controller 102 may be structured as an electronic control module ("ECM"). The ECM may include a transmission control unit and any other control unit included in a vehicle (e.g., engine control unit, powertrain control module, exhaust aftertreatment control unit, etc.). In some embodiments, the controller 102 may be implemented as a J1939 data link device.

[0028] Referring now to Fig. 2, a block diagram illustrating the function and structure of the controller 102 is shown according to an embodiment. The controller 102 includes a processing circuit 202 including a processor 204 and a memory 206. The processor 204 may be implemented as a general-purpose processor, an application specific integrated circuit (ASIC), one or more field programmable gate arrays (FPGAs), a digital signal processor (DSP), a group of processing components, or other suitable electronic processing components. The one or more memory devices 206 (e.g., RAM, ROM, Flash Memory, hard disk storage, etc.) may store data and/or computer code for facilitating the various processes described herein. Thus, the one or more memory devices 206 may be communicably connected to the controller 102 and provide computer code or instructions to the controller 102 for executing the processes described in regard to the controller 102 herein. Moreover, the one or more memory devices 206 may be or include tangible, non- transient volatile memory or non-volatile memory. Accordingly, the one or more memory devices 206 may include database components, object code components, script

components, or any other type of information structure for supporting the various activities and information structures described herein. [0029] The memory 206 is shown to include various modules for completing the activities described herein. More particularly, the memory 206 includes an out-of-gear detection module 208, a gear determination module 210, and a speed synchronization module 212. The modules are configured to detect an out-of-gear status, to determine a desired gear, and to selectively synchronize engine 106 speed and transmission 108 input speed for the desired gear. While various modules with particular functionality are shown in Fig. 2, it should be understood that the controller 102 and memory 206 may include any number of modules for completing the functions described herein. For example, the activities of multiple modules may be combined as a single module, as additional modules with additional functionality may be included, etc. Further, it should be understood that the controller 102 may further control other vehicle activity beyond the scope of the present disclosure.

[0030] Certain operations of the controller 102 described herein include operations to interpret and/or to determine one or more parameters. Interpreting or determining, as utilized herein, includes receiving values by any method known in the art, including at least receiving values from a datalink or network communication, receiving an electronic signal (e.g. a voltage, frequency, current, or PWM signal) indicative of the value, receiving a computer generated parameter indicative of the value, reading the value from a memory location on a non-transient computer readable storage medium, receiving the value as a run-time parameter by any means known in the art, and/or by receiving a value by which the interpreted parameter can be calculated, and/or by referencing a default value that is interpreted to be the parameter value.

[0031] According to various embodiments, the controller 102 is structured to receive various input parameters, such as engine speed 214, engine acceleration 216, engine torque output 218, transmission output speed 220, vehicle speed 222, grade 224, and operator I/O 226. For example, the controller 102 may receive such input parameters from the sensors 128, the I/O interface 130, and/or other components of the system 100.

[0032] The out-of-gear detection module 208 is structured to determine an out-of-gear status. The out-of-gear status may be determined based on various parameters, such as engine speed 214, engine acceleration 216 (positive and negative, e.g., deceleration), engine torque output 218, transmission output speed 220, vehicle speed 222, grade 224, vehicle acceleration (positive and negative, e.g., deceleration), accelerator pedal position, brake pedal position, clutch pedal position, grade and/or other parameters. In some embodiments, the out-of-gear status is determined by detecting a decoupling of the engine 106 speed and the transmission 108 speed, and a reduction in torque output from the engine 106. Unlike conventional systems, the out-of-gear status may be determined without receiving a signal indicating any of shift lever operation, clutch pedal engagement, and clutch engagement.

[0033] In some embodiments, vehicle speed is used to trigger out-of-gear status. Vehicle speed may be determined, for example, a ratio including desired gear, rear axle ratio, and/or tire size. The commanded engine speed may be recalculated frequently based on vehicle speed. The command may be sent for a specific time period to allow the operator to engage the gear. Various settings allow for adjustments based on experience level, such as increasing the engagement time for inexperienced operators.

[0034] The gear determination module 210 is structured to determine a desired gear upon the out-of-gear detection module 208 detecting the out-of-gear status. In some embodiments, the gear determination module 210 may monitor the pre-shift engine speed 214 to determine the present gear and/or to predict the desired gear. For example, (1) if the engine speed 214 is above 1600 RPM, a skip up-shift is assumed; (2) if the engine speed 214 is between 1200 RPM and 1600 RPM, a single up-shift is assumed; (3) if the engine speed 214 is between 1000 RPM and 1200 RPM, a single down- shift is assumed; and (4) if the engine speed 214 is below 1000 RPM, a skip-down shift is assumed.

[0035] Additionally, a trigger may be set based on other parameters. For example, if the vehicle is decelerating while in a high power condition and the engine speed 214 falls below a threshold, then a downshift should be expected. If under this scenario, the accelerator is in a low position (e.g., not depressed or slightly depressed, such as less than 25 percent depressed), a single downshift could be assumed. If under this scenario, the accelerator is in a high accelerator position (e.g., significantly depressed, such as greater than 75 percent depressed), a double downshift may be assumed. In some embodiments, a trigger may be set based upon whether the vehicle accelerating prior to the out-of-gear being detected with sufficiently high engine speed, during which an upshift may be assumed. [0036] Some embodiments may also include a grade parameter 224 (e.g., from a grade sensor), which may provide further opportunities to determine the appropriateness of the future gear selection. For example, if the vehicle is travelling downhill, the engine 106 is absorbing negative torque and the load on the gear teeth may not allow the transmission 108 to be shifted out of gear. Therefore, the operator may blip the throttle pedal to disengage the gear. Therefore, in such a situation, a throttle blip may indicate an out-of- gear status.

[0037] The speed synchronization module 212 is structured to determine the

transmission 108 input speed for the desired gear determined by the gear determination module 210, and to control engine 106 speed to synchronize the engine 106 speed with the transmission 108 input speed for the desired gear. The transmission input speed may be determined by cross-referencing the engine speed and the vehicle speed with a look-up table. In some embodiments, the controller 102 may transmit speed synchronization commands via torque speed control 1 (TSC #1) messages over a vehicle bus, such as J1939.

[0038] In some embodiments, the controller 102 is configured to increase the accelerator percentage to increase vehicle speed in the new gear. This may be repeated for each new gear. In some embodiments, the controller 102 includes a function during engine lug backs that leads to the need for a downshift. The scenario is similar to the upshift, with the driver lifting on the throttle for a period of time to get out-of-gear. Then, the driver would modulate the throttle pedal in order to increase the engine speed to synchronize in a lower gear.

[0039] In some embodiments, the commanded engine speed may be a ratio based on vehicle speed. Determining the ratios for each gear in the system necessitates either a modifiable list of ratios to use for each gear, a learning mode in which the gears can be re- identified, or a self-calibration that occurs as the vehicle is driven normally.

[0040] Referring to Fig. 3, a gearshift plot illustrating engine speed versus vehicle speed is shown. In particular, Fig. 3 includes a first trace 302 that shows engine speed versus vehicle speed for upshifts, and a second trace 304 that shows engine speed versus vehicle speed for downshifts. In-gear operation lies on a fixed-slope line that represents the transmission gear ratio multiplied by a constant (e.g., tire size and rear axle ratio). As shown in Fig. 3, in the case of a 10-speed transmission, there are ten discrete slopes. In some embodiments, the out-of-gear detection module may determine an out-of-gear event based on a change in slope of this plot. In other embodiments, out-of-gear events may be triggered by throttle blips.

[0041] Fig. 4 is a flow diagram of a method 400 of synchronizing engine speed with transmission speed, according to an embodiment. The method 400 may be performed, for example, by the controller 102 of Figs. 1 and 2 or by other control devices.

[0042] At 402, shift event out of a first gear of a manual transmission is detected. The shift event may be detected, for example, based on at least one of speed, acceleration, and torque of an engine, the engine and the transmission comprising a powertrain system of a vehicle. In one embodiment, detection of the shift event is not based on a signal indicating any of shift lever operation, clutch pedal engagement, and clutch engagement. In another embodiment, detection of the shift event is based on a detected decoupling of engine speed and transmission output speed.

[0043] At 404, the first gear out of which the transmission was shifted is determined. For example, the first gear may be determined by cross-referencing engine speed and vehicle speed prior to the shift event with a first look-up table.

[0044] At 406, a desired gear is predicted. For example, the desired gear may be predicted based on the first gear and at least one of engine speed, vehicle speed, and vehicle acceleration. In some embodiments, the ratio steps between consecutive gears are variable. The desired gear may be predicted based on engine speed. For example, in one embodiment, a skip up-shift is predicted if the engine speed is above 1600 RPM, a single up-shift is predicted if the engine speed is between 1200 RPM and 1600 RPM, a single down- shift is predicted if the engine speed is between 1000 RPM and 1200 RPM, and a skip-down shift is predicted if the engine speed is below 1000 RPM.

[0045] In some embodiments, the desired gear is predicted based on vehicle

acceleration, engine torque output, engine speed, and accelerator position. For example, in one embodiment, a single downshift is predicted if the vehicle is decelerating, the torque output is above a first threshold, the engine speed is below a second threshold, and the accelerator is less than 25 percent depressed. A double downshift is predicted if the vehicle is decelerating, the torque output is above the first threshold, the engine speed is below the second threshold, and the accelerator is greater than 75 percent depressed. An upshift is predicted if the vehicle is accelerating prior to the out-of-gear shift event being detected and the engine speed is above a third threshold.

[0046] In some embodiments, the desired gear is predicted based on a grade signal indicative of a grade of a surface traveled over by the vehicle. The grade indicates that the vehicle is traveling uphill or downhill. In one embodiment, a downshift is predicted if the grade signal indicates that the vehicle is traveling uphill, and an upshift is predicted if the grade signal indicates that the vehicle is traveling downhill.

[0047] At 408, the transmission input speed for the desired gear is determined. For example, the transmission input speed for the desired gear may be determined by cross- referencing the engine speed and the vehicle speed with a second look-up table.

[0048] At 410, engine speed is controlled to synchronize the engine speed with the transmission input speed for the desired gear. The engine speed may be controlled for a predetermined time period to allow the operator sufficient time to engage the desired gear. The predetermined time period may be defined based on operator experience level, allowing for longer engagement time for more inexperienced operators. In some embodiments, neutral coasting is facilitated when the transmission has not shifted into the desired gear before the time period has elapsed. In some embodiments, when upshifting, an external load is provided on the engine so as to cause the engine speed to be decreased faster than a predetermined deceleration rate associated with coasting.

[0049] It should be noted that the processes of the methods described herein may be utilized with the other methods, although described in regard to a particular method. It should further be noted that the term "example" as used herein to describe various embodiments is intended to indicate that such embodiments are possible examples, representations, and/or illustrations of possible embodiments (and such term is not intended to connote that such embodiments are necessarily extraordinary or superlative examples).

[0050] It should be noted that the term "example" as used herein to describe various embodiments is intended to indicate that such embodiments are possible examples, representations, and/or illustrations of possible embodiments (and such term is not intended to connote that such embodiments are necessarily extraordinary or superlative examples).

[0051] Example and non-limiting module implementation elements include sensors (e.g., coupled to the components and/or systems in Fig. 1) providing any value determined herein, sensors providing any value that is a precursor to a value determined herein, datalink and/or network hardware including communication chips, oscillating crystals, communication links, cables, twisted pair wiring, coaxial wiring, shielded wiring, transmitters, receivers, and/or transceivers, logic circuits, hard-wired logic circuits, reconfigurable logic circuits in a particular non-transient state configured according to the module specification, any actuator including at least an electrical, hydraulic, or pneumatic actuator, a solenoid, an op-amp, analog control elements (springs, filters, integrators, adders, dividers, gain elements), and/or digital control elements.

[0052] The schematic flow chart diagrams and method schematic diagrams described above are generally set forth as logical flow chart diagrams. As such, the depicted order and labeled steps are indicative of representative embodiments. Other steps, orderings and methods may be conceived that are equivalent in function, logic, or effect to one or more steps, or portions thereof, of the methods illustrated in the schematic diagrams.

[0053] Additionally, the format and symbols employed are provided to explain the logical steps of the schematic diagrams and are understood not to limit the scope of the methods illustrated by the diagrams. Although various arrow types and line types may be employed in the schematic diagrams, they are understood not to limit the scope of the corresponding methods. Indeed, some arrows or other connectors may be used to indicate only the logical flow of a method. For instance, an arrow may indicate a waiting or monitoring period of unspecified duration between enumerated steps of a depicted method. Additionally, the order in which a particular method occurs may or may not strictly adhere to the order of the corresponding steps shown. It will also be noted that each block of the block diagrams and/or flowchart diagrams, and combinations of blocks in the block diagrams and/or flowchart diagrams, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and program code. [0054] Many of the functional units described in this specification have been labeled as modules, in order to more particularly emphasize their implementation independence. For example, a module may be implemented as a hardware circuit comprising custom VLSI circuits or gate arrays, off-the-shelf semiconductors such as logic chips, transistors, or other discrete components. A module may also be implemented in programmable hardware devices such as field programmable gate arrays, programmable array logic, programmable logic devices or the like.

[0055] Modules may also be implemented in machine-readable medium for execution by various types of processors. An identified module of executable code may, for instance, comprise one or more physical or logical blocks of computer instructions, which may, for instance, be organized as an object, procedure, or function. Nevertheless, the executables of an identified module need not be physically located together, but may comprise disparate instructions stored in different locations which, when joined logically together, comprise the module and achieve the stated purpose for the module.

[0056] Indeed, a module of computer readable program code may be a single instruction, or many instructions, and may even be distributed over several different code segments, among different programs, and across several memory devices. Similarly, operational data may be identified and illustrated herein within modules, and may be embodied in any suitable form and organized within any suitable type of data structure. The operational data may be collected as a single data set, or may be distributed over different locations including over different storage devices, and may exist, at least partially, merely as electronic signals on a system or network. Where a module or portions of a module are implemented in machine-readable medium (or computer-readable medium), the computer readable program code may be stored and/or propagated on in one or more computer readable medium(s).

[0057] The computer readable medium may be a tangible computer readable storage medium storing the computer readable program code. The computer readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, holographic, micromechanical, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. [0058] More specific examples of the computer readable medium may include but are not limited to a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a portable compact disc read-only memory (CD-ROM), a digital versatile disc (DVD), an optical storage device, a magnetic storage device, a holographic storage medium, a micromechanical storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, and/or store computer readable program code for use by and/or in connection with an instruction execution system, apparatus, or device.

[0059] The computer readable medium may also be a computer readable signal medium. A computer readable signal medium may include a propagated data signal with computer readable program code embodied therein, for example, in baseband or as part of a carrier wave. Such a propagated signal may take any of a variety of forms, including, but not limited to, electrical, electro-magnetic, magnetic, optical, or any suitable combination thereof. A computer readable signal medium may be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport computer readable program code for use by or in connection with an instruction execution system, apparatus, or device. Computer readable program code embodied on a computer readable signal medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, Radio Frequency (RF), or the like, or any suitable combination of the foregoing

[0060] In one embodiment, the computer readable medium may comprise a combination of one or more computer readable storage mediums and one or more computer readable signal mediums. For example, computer readable program code may be both propagated as an electro-magnetic signal through a fiber optic cable for execution by a processor and stored on RAM storage device for execution by the processor.

[0061] Computer readable program code for carrying out operations for aspects of the present invention may be written in any combination of one or more programming languages, including an object oriented programming language such as Java, Smalltalk, C++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone computer-readable package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider).

[0062] The program code may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function/act specified in the schematic flowchart diagrams and/or schematic block diagrams block or blocks.

[0063] Accordingly, the present disclosure may be embodied in other specific forms without departing from its spirit or essential characteristics. The described embodiments are to be considered in all respects only as illustrative and not restrictive. The scope of the disclosure is, therefore, indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.

Claims

WHAT IS CLAIMED IS:

1. A method, comprising:

detecting a shift event out of a first gear of a manual transmission based on at least one of speed, acceleration, and torque of an engine, the engine and the

transmission comprising a powertrain system of a vehicle;

determining the first gear based on each of engine speed and vehicle speed prior to the shift event;

predicting a desired gear based on the first gear and at least one of engine speed, vehicle speed, and vehicle acceleration;

determining the transmission input speed for the desired gear based on each of the engine speed and the vehicle speed; and

controlling engine speed to synchronize the engine speed with the transmission input speed for the desired gear.

2. The method of claim 1 , wherein detection of the shift event is not based on a signal indicating any of shift lever operation, clutch pedal engagement, and clutch engagement.

3. The method of claim 1, wherein detection of the shift event is further based on a detected decoupling of engine speed and transmission output speed.

4. The method of claim 1, wherein the transmission includes a plurality of gears, wherein at least two ratio steps between consecutive gears are not equal.

5. The method of claim 1 ,

wherein a skip up-shift is predicted if the engine speed is above 1600 RPM, wherein a single up-shift is predicted if the engine speed is between 1200 RPM and 1600 RPM,

wherein a single down-shift is predicted if the engine speed is between 1000 RPM and 1200 RPM, and

wherein a skip-down shift is predicted if the engine speed is below 1000

RPM.

6. The method of claim 1,

wherein a single downshift is predicted if the vehicle is decelerating, the torque output is above a first threshold, the engine speed is below a second threshold, and the accelerator is less than 25 percent depressed,

wherein a double downshift is predicted if the vehicle is decelerating, the torque output is above the first threshold, the engine speed is below the second threshold, and the accelerator is greater than 75 percent depressed, and

wherein an upshift is predicted if the vehicle is accelerating prior to the out- of-gear shift event being detected and the engine speed is above a third threshold.

7. The method of claim 1, further comprising receiving a grade signal indicative of a grade of a surface traveled over by the vehicle, the grade indicating that the vehicle is traveling uphill or downhill,

wherein a downshift is predicted if the grade signal indicates that the vehicle is traveling uphill, and

wherein an upshift is predicted if the grade signal indicates that the vehicle is traveling downhill.

8. The method of claim 1 , wherein the transmission input speed for the desired gear is a first transmission input speed, wherein a predetermined time period is associated with the first transmission input speed, and further comprising determining, if the transmission is not shifted into the desired gear before the predetermined time period has elapsed, a second transmission input speed for the desired gear.

9. The method of claim 8, further comprising facilitating neutral coasting when the transmission has not shifted into the desired gear before the time period has elapsed.

10. The method of claim 1, wherein the second gear is higher than the first gear, and further comprising providing, by the processor, an external load on the engine so as to cause the engine speed to be decreased faster than a predetermined deceleration rate associated with coasting.

11. A system, comprising:

a powertrain system of a vehicle, the powertrain system including an engine and a manual transmission; and

a controller in operative communication with the powertrain system, the controller structured to:

detect a shift event out of a first gear of the transmission based on at least one of speed, acceleration, and torque of the engine, the engine being operably coupled to the manual transmission;

determine the first gear based on each of engine speed and vehicle speed prior to the shift event;

predict a desired gear based on the first gear and at least one of engine speed, vehicle speed, and vehicle acceleration;

determine the transmission input speed for the desired gear based on each of the engine speed and the vehicle speed; and

control engine speed to synchronize the engine speed with the transmission input speed for the desired gear.

12. The system of claim 11 , wherein detection of the shift event is not based on a signal indicating any of shift lever operation, clutch pedal engagement, and clutch engagement.

13. The system of claim 11, further comprising detecting a decoupling of engine speed and transmission output speed, wherein detection of the shift event is further based on the detected decoupling of the engine speed and the transmission output speed.

14. The system of claim 11 , wherein the transmission includes a plurality of gears, wherein at least two ratio steps between consecutive gears are not equal.

15. The system of claim 11 ,

wherein a skip up-shift is predicted if the engine speed is above 1600 RPM, wherein a single up-shift is predicted if the engine speed is between 1200

RPM and 1600 RPM,

wherein a single down-shift is predicted if the engine speed is between

1000 RPM and 1200 RPM, and wherein a skip-down shift is predicted if the engine speed is below 1000

RPM.

16. The system of claim 11 ,

17. The system of claim 11, further comprising receiving a grade signal indicative of a grade of a surface traveled over by the vehicle, the grade indicating that the vehicle is traveling uphill or downhill,

18. The system of claim 11 ,

wherein the transmission input speed for the desired gear is a first transmission input speed, wherein a predetermined time period is associated with the first transmission input speed, and

further comprising determining, if the transmission is not shifted into the desired gear before the predetermined time period has elapsed, a second transmission input speed for the desired gear.

19. The system of claim 18, further comprising facilitating neutral coasting when the transmission has not shifted into the desired gear before the predetermined time period has elapsed.

20. The system of claim 11 ,

wherein the second gear is higher than the first gear, and further comprising providing an external load on the engine so as to cause the engine speed to be decreased faster than a predetermined deceleration rate associated with coasting.

21. A controller in operative communication with a powertrain system of a vehicle, the controller structured to:

detect an out-of-gear shift event of a transmission based on detecting each of a decoupling of engine speed and transmission output speed, and a reduction in torque output from an engine, the powertrain system including the engine and the transmission;

predict a desired gear based at least in part on a prior gear and at least one of engine speed, vehicle speed, and vehicle acceleration;

22. The system of claim 21, wherein detection of the shift event is not based on a signal indicating any of shift lever operation, clutch pedal engagement, and clutch engagement.

23. The system of claim 21, further comprising detecting a decoupling of engine speed and transmission output speed, wherein detection of the shift event is further based on the detected decoupling of the engine speed and the transmission output speed.

24. The system of claim 21 , wherein the transmission includes a plurality of gears, wherein at least two ratio steps between consecutive gears are not equal.