Declutch clunk mitigation through torque intervention

A vehicle system, comprising:

• a prime mover;
• a driveline including a manual transmission coupled to the prime mover, wherein the prime mover includes a shift selector;
• an accelerator pedal coupled to the prime mover;
• an accelerator pedal position sensor configured to determine an accelerator pedal position of the accelerator pedal;
• a clutch pedal coupled to the manual transmission;
• a clutch position sensor coupled to the clutch pedal to determine a clutch pedal position;
• a controller in communication with the prime mover, the accelerator pedal position sensor, and the clutch position sensor, wherein the controller is programmed to:
• determine a current torque request based on the accelerator pedal position of an accelerator pedal of the vehicle system;
• determine the clutch pedal position based on a clutch position signal received from the clutch position sensor;
• determine a clutch pedal speed based on a change of the clutch pedal position over time;
• modify the current torque request to obtain a modified torque request as a function of the clutch pedal position and the clutch pedal speed such that a stored potential energy in the driveline is minimized by a time that the clutch pedal of the vehicle system is disengaged during a declutch event of the manual transmission of the vehicle system;
• and
• control the prime mover to adjust an output torque thereof in accordance with the modified torque request.

A vehicle system, comprising:

• a prime mover configured to provide propulsion to the vehicle system;
• a driveline including a manual transmission coupled to the prime mover, wherein the manual transmission includes a plurality of gear ratios, the manual transmission includes a shift selector configured to select among the plurality of gear ratios of the manual transmission, and the plurality of gear ratios includes a first gear ratio, a second gear ratio, a third gear ratio, a fourth gear ratio, and a fifth gear ratio, and the first gear ratio is greater than the second gear ratio, and the manual transmission includes a transmission output shaft;
• a shift-linkage position sensor coupled to the shift selector of the manual transmission such that the shift-linkage position sensor is configured to determine a currently engaged gear ratio of the plurality of gear ratios, wherein the shift-linkage position sensor is configured to generate a shift signal representative of the currently engaged gear ratio of the manual transmission;
• a transmission output speed sensor coupled to the transmission output shaft of the manual transmission such that the transmission output speed sensor is configured to monitor and measure a shaft speed of the transmission output shaft of the manual transmission, wherein the transmission output speed sensor is configured to generate a shaft speed signal representative of the shaft speed of the transmission output shaft and a current vehicle speed of the vehicle system;
• a clutch coupled between the prime mover and the manual transmission, wherein:
• the clutch is movable between an engaged position and a disengaged position;
• in the engaged position, the clutch interconnects the prime mover to the manual transmission such that torque is transmitted from the prime mover to the manual transmission;
• and
• in the disengaged position, the clutch decouples the prime mover from the manual transmission such that no torque is transmitted between the prime mover and the manual transmission;
• an accelerator pedal coupled to the prime mover;
• an accelerator pedal position sensor coupled to the accelerator pedal such that the accelerator pedal position sensor is configured to determine an accelerator pedal position of the accelerator pedal;
• a clutch pedal coupled to the clutch, wherein actuation of the clutch pedal causes the clutch to move between the disengaged position and the engaged position;
• a clutch position sensor coupled to the clutch pedal such that the clutch position sensor is configured to determine a clutch pedal position, wherein the clutch position sensor is configured to generate a clutch position signal representative of the clutch pedal position;
• a controller in communication with the shift-linkage position sensor, the transmission output speed sensor, the accelerator pedal position sensor, and the clutch position sensor, wherein the controller is programmed to:
• determine a currently engaged transmission gear ratio on the shift signal received from the shift-linkage position sensor;
• compare the currently engaged transmission gear ratio with a predetermined gear ratio, wherein the predetermined gear ratio is at least one of the first gear ratio and the second gear ratio;
• determine that the currently engaged transmission gear ratio is the predetermined gear ratio;
• determine the current vehicle speed of the vehicle system based on the shaft speed signal received from the transmission output speed sensor;
• compare the current vehicle speed of the vehicle system with a predetermined speed value;
• determine that the current vehicle speed of the vehicle system is less than the predetermined speed value;
• determine a current accelerator pedal speed of the accelerator pedal of the vehicle system based on a change of the accelerator pedal position over time;
• compare the current accelerator pedal speed with a predetermined speed threshold;
• determine that the current accelerator pedal speed is less than the predetermined speed threshold;
• determine a current torque request based on the accelerator pedal position of the accelerator pedal of the vehicle system;
• determine the clutch pedal position based on the clutch position signal received from the clutch position sensor;
• determine a clutch pedal speed based on a change of the clutch pedal position over time;
• and
• modify the current torque request to obtain a modified torque request as a function of the clutch pedal position and the clutch pedal speed such that a stored potential energy in the driveline is minimized by a time that the clutch pedal of the vehicle system is disengaged during a declutch event of the manual transmission of the vehicle system in response to:
• determining that the currently engaged transmission gear ratio is the predetermined gear ratio;
• determining that the current vehicle speed of the vehicle system is less than the predetermined speed value;
• and
• determining that the current accelerator pedal speed is less than the predetermined speed threshold;
• and
• control the prime mover to adjust an output torque thereof in accordance with the modified torque request.