CLUTCH-TO-CLUTCH TRANSMISSION MONITORING SYSTEM FOR SINGLE-MOTOR VEHICLES

Abstract

Clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12), comprising: control software (30) that generates a control signal (46); a monitor (22, 24, 26, 28) in communication with the control software (30); and a pre-calculation monitor (32) in communication with the control software (30), the pre-calculation monitor (32) receiving input data (40, 64, 82, 100) different from the control signal and outputting an operating threshold signal (44, 66, 84, 102) to the control software (30), the operating threshold signal defining permissible operating limits for at least one component in communication with the monitor; characterized in that the pre-calculation monitor (32) determines the operating threshold signal based on a driver request or a PRNDL (Park - Reverse - Neutral - Drive - Low) position; wherein the clutch-to-clutch transmission monitoring system further comprises a post-calculation monitor (34) in communication with the control software (30) and the pre-calculation monitor (32), the post-calculation monitor (34) receiving both the control signal (46) and the operating threshold signal and for determining whether the control signal (46) exceeds the permissible operating limits defined by the pre-calculation monitor (32); wherein the control software (30) is supplemented by additional software checks, the additional software checks ensuring that the threshold values identified by the operating threshold signal, which were determined by the pre-calculation monitor (32), are not violated.

Description

INTRODUCTION

[0001] The present disclosure relates to a clutch-to-clutch transmission monitoring system according to the preamble of claim 1 for a motor vehicle, as is essentially known from DE 11 2008 003 136 T5.

[0002] Further prior art can be found in the documents US 2014 / 0 336 864 A1, DE 10 2010 008 465 A1, DE 10 2005 037 516 A1 and DE 10 2007 063 212 B4.

[0003] Automatic transmission designs with automatic planetary gears and dual-clutch transmissions, hereinafter referred to as "clutch-to-clutch transmissions," provide control software for controlling functions including, but not limited to, sequence control, clutch pressure regulation, diagnostics, and the like. Control software (SW) communicates directly with a hardware input and output (HWIO) module. In newer transmission designs, a software (SW) monitor has been added in parallel to the control software (SW) and the HWIO module.The purpose of the SW monitor is to monitor the output command signals from the control software (SW) to prevent commanding too low a gear, such as a gear change from eighth gear to first gear, a command for too many clutches, or a command for a clutch combination that would result in engagement of the transmission output shaft, such as a command for a forward clutch in combination with a reverse clutch.

[0004] A hazard, such as unintended deceleration (UD) or unintended direction, including unintended acceleration, can occur if the control software (SW) that governs transmission operation is corrupted or has faulty calibrations or algorithm errors. Current transmission designs set a code when predetermined hazard criteria are met. The transmission control sets a safe condition, which can cause the transmission to enter a mechanical-hydraulic fault and trigger an engine hazard warning. These results can impair a driver's ability to enter a drive command.

[0005] Thus, while current software control monitors serve their purpose, there is a need for a new and improved system and method for monitoring and controlling automatic transmissions. SUMMARY

[0006] According to the invention, a clutch-to-clutch transmission monitoring system for a motor vehicle is presented, which is characterized by the features of claim 1.

[0007] In another aspect of the present disclosure, a failure timer is triggered by the post-calculation monitor when the control signal exceeds the allowable operating limits defined by the pre-calculation monitor.

[0008] In another aspect of the present disclosure, a hardware input and output (HWIO) module receives the control signal and performs control functions for the at least one component in communication with the monitor and further in communication with the failure timer.

[0009] In another aspect of the present disclosure, after a predetermined period of operation of the failure timer, the post-calculation monitor issues a fault command to the HWIO module to cease operation of the at least one component.

[0010] In another aspect of the present disclosure, the monitor defines a command shift monitor for unintended vehicle deceleration due to engine overspeed caused by reaching a gear too low for a current vehicle speed.

[0011] In another aspect of the present disclosure, the pre-calculation monitor determines the allowable operating limits of a lowest allowable gear based on a driver request and considers the allowable operating limits when generating the operating threshold signal.

[0012] In another aspect of the present disclosure, the monitor defines a ratio monitor for an incorrect direction of the vehicle when the vehicle starts moving from a stopped position.

[0013] In another aspect of the present disclosure, the pre-calculation monitor confirms that the transmission is configured for either reverse or forward gear through the use of a calculated sign ratio.

[0014] In another aspect of the present disclosure, the monitor defines a connection monitor for unintended vehicle deceleration due to additional clutches being commanded when they should be off.

[0015] In another aspect of the present disclosure, when the transmission defines an automatic planetary transmission, the precalculation monitor identifies whether normally OFF clutches for a desired gear indicate ON, indicating a connected condition; or when the transmission defines a dual-clutch transmission, the precalculation monitor confirms that each of the two clutches is not permanently engaged.

[0016] In another aspect of the present disclosure, the monitor defines an area monitor for an incorrect commanded direction of the vehicle.

[0017] In another aspect of the present disclosure, the pre-calculation monitor identifies the allowable clutch combinations via a PRNDL (Park - Reverse - Neutral - Drive - Low) position.

[0018] According to several aspects, a clutch-to-clutch transmission monitoring system for a motor vehicle includes control software that receives input data from multiple systems of a motor vehicle and generates a control signal. A monitor communicates with the control software. A pre-calculation monitor is in communication with the control software. The operating threshold signal defines the allowable operating limits for at least one component in communication with the monitor. The post-calculation monitor receives both the control signal and the operating threshold signal. The post-calculation monitor compares the control signal to the operating threshold signal to determine whether the control signal violates the allowable operating limits defined by the pre-calculation monitor.A failure timer is triggered by the recalculation monitor when the control signal exceeds the specified permissible operating limits. A hardware input and output (HWIO) module in communication with the failure timer opens drivers for multiple clutches when a fault signal is generated by the recalculation monitor after a specified failure timer operating time.

[0019] In another aspect of the present disclosure, a calibration monitor performs the calculation of the vehicle speed and the permissible gears. A memory is provided in which the calculations are stored in the calibration monitor.

[0020] In another aspect of the present disclosure, the calibration monitor is included with the pre-calculation monitor.

[0021] Further areas of applicability will become apparent from the description provided herein. It should be noted that the description and specific examples are for illustrative purposes only. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The drawings described herein are for illustrative purposes only. Fig. 1 is a flowchart of a clutch-to-clutch transmission monitoring system according to an exemplary embodiment; Fig. 2 is a flowchart illustrating a pre-computation monitor and a post-computation monitor in conjunction with an instruction relocation monitor according to an exemplary embodiment; Fig. 3 is a flowchart illustrating a pre-calculation monitor and a post-calculation monitor in conjunction with a ratio monitor according to an exemplary embodiment; Fig. 4 is a flowchart illustrating a pre-computation monitor and a post-computation monitor in conjunction with a connection monitor according to an exemplary embodiment; and Fig. 5 is a flowchart illustrating a pre-calculation monitor and a post-calculation monitor in conjunction with a range monitor according to an exemplary embodiment. DETAILED DESCRIPTION

[0023] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses.

[0024] With reference to Fig. 1, the high-level control feature of a clutch-to-clutch transmission monitoring system 10 provides multiple monitoring functions for a motor vehicle 12 having a prime mover 14, such as an engine, connected to a transmission 16 and providing drive power to at least one driven wheel 18. The transmission 16 may be a clutch-to-clutch transmission, such as a dual-clutch transmission or an automatic planetary transmission. The transmission 16 may include multiple clutches 20 with at least one clutch for engaging a gear. For example, an automatic planetary transmission may include five clutches acting in sets of three or push clutches to achieve an intended forward gear ratio and at least one reverse gear ratio. Each of the clutches 20 is individually controlled via a solenoid-operated driver that defines the high- and low-side drivers 21.The power supply to the drivers 21 may be shut off under certain conditions defined herein, thereby protecting the transmission 16 by forcing the transmission into a mechanical-hydraulic fault.

[0025] The monitoring functions of the monitoring system 10 include several monitors, including a command shift monitor 22, a ratio monitor 24, a linkage monitor 26, and a range monitor 28. The command shift monitor 22 protects against unintended vehicle deceleration due to engine overspeed caused by reaching a gear too low for a current vehicle speed. Such a condition would revert the engine to a very high, unsafe speed. The ratio monitor 24 protects by monitoring for incorrect direction, as seen by a sign of a measured ratio, when the vehicle 12 begins to move from a stopped position.The connection monitor 26 protects against unintentional vehicle deceleration by engaging additional clutches when they should be disengaged, as indicated, for example, by configuring the clutches using clutch pressure commands. The range monitor 28 protects against an incorrect direction command, as indicated by configuring the clutches using clutch pressure commands.

[0026] Each of the monitors 22, 24, 26, 28 receives inputs, including, but not limited to, target range, shift state enumerations, commanded gear, brake position, clutch pressure, clutch fluid levels, vehicle speed, and the like. Each of the monitors generates one or more signals that define remedial actions based on the inputs and the vehicle condition. The monitors are also in communication with control software (SW) 30, which generates command signals based on the inputs.

[0027] To further ensure that the corrective actions controlled by each of the monitors include permissible thresholds for a current vehicle condition prior to generating a control signal and that the command or control signal from each of the monitors is not based on corrupted data, for example, due to a calculation error or a memory error, the monitoring system 10 includes a pre-calculation monitor and a post-calculation monitor for data input and commands issued by the control SW 30 for each of the command shift monitors 22, the ratio monitor 24, the binding monitor 26, and the range monitor 28.

[0028] With reference to Fig. 2 and again on Fig. 1, the command shift monitor 22 utilizes, among other things, a first or pre-calculation monitor 32 and a second or post-calculation monitor 34. The input data 36 includes, among other things, the vehicle speed, which is transmitted to the control SW 30 via an input communication path 38. The pre-calculation monitor 32 also handles the diagnosis of speed sensors, high-side driver conditions, and service conditions. Normal control functions of the control SW 30 include sequencing, clutch pressure control, diagnostics, and the like. At the same time, the input data 36 is transmitted to the pre-calculation monitor 32 via the input communication path 38, but at least a portion of the input data 36 is also transmitted as input communication data 40.

[0029] The pre-calculation monitor 32 runs after all vehicle conditions, speeds, driver requests, and the like are known. The pre-calculation monitor 32 provides, for example, a calibration monitor 42 for performing vehicle speed and allowable gear calculations. The calibration monitor 42 calculates, for example, a lowest allowable gear by determining a gear limit when the vehicle speed is above a predetermined threshold. As a first software monitoring function for the command shift monitor 22, the pre-calculation monitor 32 determines the allowable shift thresholds of the lowest allowable gear based on a driver request (i.e., range) and publishes them in a shift threshold signal 44, which is communicated to each of the controllers SW 30 and to the post-calculation monitor 34.The operating threshold signal 44 indicates permissible thresholds or operating limits for a current vehicle state.

[0030] Exemplary thresholds or operating limits identified by the operating threshold signal 44 may include limiting transmission shifts. Such changes may, for example, limit the gear ratio from a predetermined gear, such as during highway operation in a high gear such as eighth gear, to a gear below second gear. The limits may also include monitoring for bad ratio changes that may be caused by computer code corruption, an electronic pulse generating corrupted code, and the like.

[0031] In addition to the normal functions of the controller SW 30, the functions of the controller SW 30 are supplemented by additional software checks. The additional software checks ensure that the thresholds identified by the operating threshold signal 44, which were determined by the pre-calculation monitor 32, are not exceeded. After executing the normal control functions plus the aforementioned additional software checks, a control signal 46 is generated and transmitted from the controller SW 30 to a hardware input and output (HWIO) module 48 and to the post-calculation monitor 34. The post-calculation monitor 34 thus receives two inputs: the first input being the operating threshold signal 44 generated by the pre-calculation monitor 32, which is the same signal input to the controller SW 30, and the second input being the control signal 46 output by the controller SW 30.

[0032] As a second software monitoring function of the monitoring system 10 for the command displacement monitor 22, the post-computation monitor 34 monitors the control signal 46 output by the controller SW 30 and compares the control signal 46 to the allowable operating limits identified by the operating threshold signal 44 of the pre-computation monitor 32. Typically, at least 99% or more of the control signals 46 transmitted by the controller SW 30 are expected to be within the operating limits identified by the operating threshold signal 44 generated by the pre-computation monitor 32. Therefore, most of the control signals 46 generated by the controller SW 30 are identified by the post-computation monitor 34 as being within the operating limits upon transition to the HWIO module 48.

[0033] If the post-calculation monitor 34 detects that a control output assigned to the control signal 46 exceeds one of the permissible operating limits identified by the operating threshold signal 44 of the pre-calculation monitor 32, a failure timer 50 starts. The post-calculation monitor 34 does not directly disturb the control signal 46 before it passes to the HWIO module 48, but continuously checks the control signal 46 output by the controller SW 30 to determine whether the control signal 46 is within the permissible operating limits.

[0034] Finally, when the failure timer 50 indicates that a predetermined amount of downtime has accumulated, such as a predicted hazardous condition such as an incorrect shift command lasting 200 milliseconds or longer, a fault signal 52 is generated and forwarded by the recalculation monitor 34 to the HWIO module 48, which operates similarly to known transmission control systems to establish a predetermined safe transmission condition, for example, by pulling power to the high-side clutch solenoid drivers. The failure signal 52, if generated, is expected to be due to a calculation problem that is not part of the software, such as data corruption or a memory problem.

[0035] The calculations performed in the pre-calculation monitor 32 are also stored in a memory 54. The data stored in memory 54 can thus be accessed for subsequent loops of the program.

[0036] With reference to Fig. 3 and again on the Fig. 1 and Fig. 2, the monitoring functions for the ratio monitor 24 are used, including a first or pre-calculation monitor 56 and a second or post-calculation monitor 58. The input data 60 includes, but is not limited to, signed TIS and TOS, clutch slip, engine speed, and PRNDL position, which are communicated to the controller SW 30 via an input communication path 62. The pre-calculation monitor 56 also analyzes diagnostics from speed sensors, high-side driver conditions, and service conditions. The expected direction is dictated by the PRNDL position.

[0037] Simultaneously, the input data 60 is transmitted to the controller SW 30 via the input communication path 62; at least a portion of the input data 60 is also transmitted as input communication data 64 to the precalculation monitor 56. As the first software monitoring function for the ratio monitor 24, the precalculation monitor 56 validates the configuration of the transmission 16 for reverse or forward drive by using a calculated sign ratio, expected clutch slip, and ratio binning. For example, a binning set of x.5 is drive 1 and x.9 is reverse drive, so these unique numbers also represent the direction relative to a neutral state. The precalculation monitor 56 further validates the configuration of the transmission 16 for reverse or forward drive by using the torque converter speed ratio to determine whether torque is being transmitted, as well as the vehicle speed.The pre-calculation monitor 56 publishes this in an operating threshold signal 66, which is transmitted to each of the controllers SW 30 and to the post-calculation monitor 58. The operating threshold signal 66 indicates permissible thresholds or operating limits for a current vehicle condition.

[0038] Additional software checks added to the controller SW 30 ensure that the thresholds identified by the operating threshold signal 66, determined by the pre-computation monitor 56, are not exceeded. After performing the normal control functions plus performing the aforementioned additional software checks, a control signal 68 is generated and transmitted from the controller SW 30 to the hardware input and output (HWIO) module 48 and to the post-computation monitor 58. The post-computation monitor 58 thus receives two inputs: the first input being the operating threshold signal 66 generated by the pre-computation monitor 56, which is the same signal input to the controller SW 30, and the second input being the control signal 68 output by the controller SW 30.

[0039] As a second software monitoring function of the monitoring system 10 for the ratio monitor 24, the post-calculation monitor 58 monitors the control signal 68 output by the controller SW 30 and compares the control signal 68 with the allowable operating limits provided by the operating threshold signal 66 of the pre-calculation monitor 56. The post-calculation monitor 58 identifies whether a shift is shorter than the time allowed by an overall hazard or failure timer 70, for example, 500 ms.If the shift continues for as long as possible with a cold transmission 16, or in a condition where the post-computation monitor 58 does not agree with the driver's direction indicated by the PRNDL command, such as a negative ratio when the driver is moving forward, and within the first 150 to 300 ms, the post-computation monitor 58 causes the controller to terminate the shift by "suddenly" turning on the oncoming clutch and then evaluating the ratio, either forward or reverse. If the shift continues but the ratio matches the sign, no action is taken. If the post-computation monitor 58 senses an incorrect direction ratio, the post-computation monitor 58 sends a fail signal 72 to the HWIO module 48 to actuate the clutch high-side drivers at the 500 msec point.If the recalculation monitor 58 determines the total shift time exceeds the maximum 500 msec point specified by the failure timer 70, and the determined direction via ratio binning or clutch slip, or the like, does not match the driver command after the shift is completed, the recalculation monitor 58 sends the error signal 72 to the HWIO module 48 to attract power to the clutch high-side drivers. The failure signal 72, if generated, is expected to be due to a calculation problem that is not part of the software, such as data corruption or a memory problem.

[0040] The post-calculation monitor 58 does not directly interfere with the control signal 68 before passing to the HWIO module 48, but continuously checks the control signal 68 output by the controller SW 30 to determine whether the control signal 68 is within the permissible operating limits.

[0041] With reference to Fig. 4 and again on the Fig. 1 through 3, a first or pre-calculation monitor 74 and a second or post-calculation monitor 76 are used for the interfacing monitor 26. The input data 78 includes, but is not limited to, the PRNDL position, the target gear, and the achieved gear, which are communicated to the controller SW 30 via an input communication path 80. The pre-calculation monitor 74 also considers the fill level of a clutch, the return spring pressure indicating that the clutch plates are contacting, TOS as an indicator of the occurrence of deceleration, and diagnostic and service checks. The expected direction is dictated by the PRNDL position.

[0042] At the same time, the input data 78 is transmitted via the input communication path 80, at least a portion of the input data 78 also as input communication data 82, to the pre-calculation monitor 74. As a first software monitoring function for the interlock monitor 26, the pre-calculation monitor 74 identifies that a transmission condition exists when the normally OFF clutch or clutches for the desired gear indicate ON. The normally OFF clutch or clutches must be above a predetermined threshold to anticipate interlocking or deceleration above a predetermined threshold. In a dual-clutch transmission, the pre-calculation monitor 74 confirms that not both clutches are always engaged. In both cases, the pre-calculation monitor 74 publishes this in an operating threshold signal 84, which is transmitted to each of the controllers SW 30 and to the post-calculation monitor 76.The operating threshold signal 84 indicates permissible thresholds or operating limits for a current vehicle condition.

[0043] Additional software checks added to the controller SW 30 ensure that the thresholds identified by the operating threshold signal 84, determined by the pre-computation monitor 74, are not exceeded. After performing the normal control functions plus performing the aforementioned additional software checks, a control signal 86 is generated and transmitted from the controller SW 30 to the hardware input and output (HWIO) module 48 and to the post-computation monitor 76. The post-computation monitor 76 thus receives two inputs: the first input being the operating threshold signal 84 generated by the pre-computation monitor 74, which is the same signal input to the controller SW 30, and the second input being the control signal 86 output by the controller SW 30.

[0044] As a second software monitoring function of the monitoring system 10 for the link monitor 26, the post-calculation monitor 76 monitors the control signal 86 output by the controller SW 30 and compares the control signal 86 with the permissible operating limits provided by the operating threshold signal 84 of the pre-calculation monitor 74. The post-calculation monitor 76 checks whether any illegal clutch combinations have been commanded. If the post-calculation monitor 76 detects an illegal clutch combination, the post-calculation monitor 76 does not provide feedback to the controller but instead triggers a failure timer 88. If the failure timer 88 runs for a predetermined time while the illegal clutch combination is still commanded, for example, 200 msec, the post-calculation monitor 76 sends an error signal 90 to the HWIO module 48 to pull the clutch's high-side drivers.The failure signal 90, when generated, is expected to be due to a computational problem that is not part of the software, such as corruption in the data or a memory problem.

[0045] The post-calculation monitor 76 does not directly interfere with the control signal 86 before passing to the HWIO module 48, but continuously checks the control signal 86 output by the controller SW 30 to determine whether the control signal 86 is within the permissible operating limits.

[0046] With reference to Fig. 5 and again on the Fig.1 through 4, the monitoring function used for the range monitor 28 includes a first or pre-calculation monitor 92 and a second or post-calculation monitor 94. The input data 96 includes, but is not limited to, the PRNDL position, which is communicated to the controller SW 30 via a first communication path 98. The pre-calculation monitor 92 also analyzes a clutch fill level, return spring pressure indicating clutch disc contact, diagnostics, and service checks.

[0047] At the same time, the input data 96 is transmitted via the first communication path 98, a portion of the input data 96 also as input communication data 100, to the pre-calculation monitor 92. As the first software monitoring function for the range monitor 28, the pre-calculation monitor 92 identifies permissible clutch combinations based on the PRNDL position via clutch connectivity detection. For example, if the transmission 16 is positioned in drive, the permissible clutch combinations cannot result in reverse. The pre-calculation monitor 92 publishes the permissible clutch combinations in an operating threshold signal 102, which is transmitted to each of the controllers SW 30 and to the post-calculation monitor 94. The operating threshold signal 102 designates permissible thresholds or operating limits for the permissible clutch combinations in the current vehicle state.

[0048] Additional software checks added to the controller SW 30 ensure that the thresholds identified by the operating threshold signal 102, determined by the pre-computation monitor 92, are not exceeded. After performing the normal control functions plus performing the aforementioned additional software checks, a control signal 104 is generated and transmitted from the controller SW 30 to the hardware input and output (HWIO) module 48 and to the post-computation monitor 94. The post-computation monitor 94 thus receives two inputs, the first input being the operating threshold signal 102 generated by the pre-computation monitor 92, which is the same signal input to the controller SW 30, and the second input being the control signal 104 output by the controller SW 30.

[0049] As a second software monitoring function of the monitoring system 10 for the range monitor 28, the post-calculation monitor 94 monitors the control signal 104 output by the controller SW 30 and compares the control signal 104 with the permissible operating limits provided by the operating threshold signal 102 of the pre-calculation monitor 92. The post-calculation monitor 94 checks whether the controller has generated an illegal clutch combination. If the post-calculation monitor 94 detects an illegal commanded clutch combination, a hazard is declared indicating that the commanded clutch combination is incorrect, and the post-calculation monitor 94 triggers a failure timer 106. If the failure timer 106 runs for a predetermined time while the invalid clutch combination is still commanded, the recalculation monitor 94 sends a fault signal 108 to the HWIO module 48 to pull the clutch high-side drivers.The failure signal 108, when generated, is expected to be due to a computational problem that is not part of the software, such as corruption in the data or a memory problem.

[0050] The post-calculation monitor 94 does not directly interfere with the control signal 104 before passing it to the HWIO module 48, but continuously checks the control signal 104 output by the controller SW 30 to determine whether the control signal 104 is within the permissible operating limits.

[0051] The hazard detection, avoidance, and mitigation method and system is deployed when a hazardous condition is detected. These include command shift point control identified with the command shift monitor 22; limit shift command control upon incorrect direction detection as indicated by the sign of a measured ratio with the ratio monitor 24; commanded tie-in when an incorrect clutch sequence occurs for a particular gear identified with the tie-in monitor 26; and a range control algorithm used when an incorrect sequence of shift occurs that is inconsistent with the driver intent identified with the range monitor 28. An engine overspeed control algorithm is also provided with the command shift monitor 22.

[0052] A clutch-to-clutch transmission monitoring system for a motor vehicle of the present disclosure offers several advantages. These include the use of a pre-calculation monitor, which analyzes the input data and sets the permissible operating limits before the controller SW, and a post-calculation monitor, which compares the control signals output by the control software with the permissible operating limits set by the pre-calculation monitor. The use of the pre-calculation monitor provides the controller SW with an input related to the vehicle condition, while the post-calculation monitor provides the ability to detect whether a calculation error has occurred in the controller SW. The data specific to each system monitor can be input to any one of several pre-calculation monitors, and each pre-calculation monitor can be associated with its own post-calculation monitor.

Claims

[1] Clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12), comprising: control software (30) that generates a control signal (46); a monitor (22, 24, 26, 28) in communication with the control software (30); and a pre-calculation monitor (32) in communication with the control software (30), the pre-calculation monitor (32) receiving input data (40, 64, 82, 100) different from the control signal and outputting an operating threshold signal (44, 66, 84, 102) to the control software (30), the operating threshold signal defining permissible operating limits for at least one component in communication with the monitor; characterized by , that the pre-calculation monitor (32) determines the operating threshold signal based on a driver request or a PRNDL (Park - Reverse - Neutral - Drive - Low) position; wherein the clutch-to-clutch transmission monitoring system further comprises a post-calculation monitor (34) in communication with the control software (30) and the pre-calculation monitor (32), the post-calculation monitor (34) receiving both the control signal (46) and the operating threshold signal and for determining whether the control signal (46) exceeds the permissible operating limits defined by the pre-calculation monitor (32); wherein the control software (30) is supplemented by additional software checks, the additional software checks ensuring that the threshold values identified by the operating threshold signal, which were determined by the pre-calculation monitor (32), are not violated. [2] The clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12) of claim 1, further comprising a failure timer (50) triggered by the post-calculation monitor (34) when the control signal (46) exceeds the allowable operating limits (44, 66, 84, 102) established by the pre-calculation monitor (32). [3] The clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12) of claim 2, further comprising a hardware input and output (HWIO) module (48) receiving the control signal (46) and performing control functions for the at least one component in communication with the monitor and further in communication with the failure timer (50). [4] The clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12) of claim 3, wherein the recalculation monitor (34) issues a fault command to the HWIO module (48) to cease operation of the at least one component after a predetermined period of operation of the failure timer (50). [5] A clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12) according to claim 1, wherein the monitor (22) defines a command shift monitor for unintended vehicle deceleration due to engine overspeed caused by reaching a gear too low for a current vehicle speed. [6] Clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12) according to claim 5, wherein the pre-calculation monitor (32) determines the permissible operating limits of a lowest permissible gear based on a driver request and takes the permissible operating limits into account when generating the operating threshold signal. [7] A clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12) according to claim 1, wherein the monitor (24) defines a ratio monitor monitoring for a wrong direction of the vehicle when the vehicle begins to move from a stop position. [8] A clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12) according to claim 7, wherein the pre-calculation monitor (32) configures the transmission (16) either backward or forward by using a calculated signed ratio. [9] A clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12) according to claim 1, wherein the monitor (26) defines monitoring for unintended vehicle deceleration due to additional clutches being activated when they should be disengaged. [10] Clutch-to-clutch transmission monitoring system (10) for a motor vehicle (12) according to claim 9, wherein: if the transmission (16) defines an automatic planetary transmission, the pre-calculation monitor (32) identifies when a normal OFF clutch for a desired gear is ON, indicating that a linkage condition exists; or if the transmission (16) defines a dual-clutch transmission, the pre-calculation monitor (32) confirms that each of two clutches is not always engaged.

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