Full clutch slip power shift of a dual clutch transmission

1. A method of controlling a dual clutch transmission, including an on-coming clutch and an off-going clutch, comprising:

generating a torque command from a launch/creep controller, the torque command including a target clutch torque;

reading the torque command using a shift logic;

implementing a preparation phase comprising:

increasing torque on the on-coming clutch to a prefill torque;

implementing a torque phase transferring torque from the off-going clutch to the on-coming clutch, the torque phase comprising:

increasing torque on the on-coming clutch towards the target clutch torque, said on-coming clutch remaining unlocked during the transfer; and

decreasing torque on the off-going clutch, said off-going clutch remaining unlocked during the transfer;

wherein as the off-going clutch torque is decreasing, the combination of the on-coming clutch torque added to the off-going clutch torque maintains the target clutch torque.

2. A method of controlling a dual clutch transmission as described in claim 1 , further comprising:

implementing a post phase comprising:

increasing torque on the on-coming clutch until it matches the target clutch torque; and

decreasing torque on the off-going clutch until the off-going clutch disconnects.

3. A method of controlling a dual clutch transmission as described in claim 2 , wherein the post phase comprises:

generating a torque command loop from the launch/creep controller;

continuously reading the torque command loop to update the target clutch torque by the shift logic; and

continuously adjusting torque on the on-coming clutch to match the updated target clutch torque.

4. A method of controlling a dual clutch transmission as described in claim 1 , wherein the off-going clutch and the on-coming clutch remain in a slipping state during the torque phase.

5. A method of controlling a dual clutch transmission as described in claim 1 , wherein the shift logic is in communication with a clutch temperature signal, said shift logic implementing the torque phase in response to the clutch temperature signal.

6. A method of controlling a dual clutch transmission as described in claim 1 , wherein the shift logic is in communication with a gear selection signal, said shift logic implementing the torque phase in response to the gear selection signal.

7. A method of controlling a dual clutch transmission as described in claim 3 , wherein the torque command loop comprises a creep loop when a pedal signal is below a predetermined value.

8. A method of controlling a dual clutch transmission as described in claim 3 , wherein the torque command loop comprises a launch loop when a pedal signal is above a predetermined value.

9. A dual clutch transmission comprising:

a launch/creep controller configured to generate torque command including a target clutch torque;

a first clutch;

a second clutch;

a clutch control assembly in communication with said launch/creep controller, said first clutch, and said second clutch, said clutch control assembly including a shift logic configured to read said torque command from said launch/creep controller, said shift logic configured to power shift by:

implement a torque phase transferring torque from the first clutch to the second clutch, the torque phase comprising:

increasing torque on the second clutch towards the target clutch torque; and

simultaneously decreasing torque on the first clutch;

wherein the first clutch and the second clutch are both in a slipping state that maintains the target clutch torque during the transfer.

10. A dual clutch transmission as described in claim 9 , wherein said shift logic is further configured to:

implement a preparation phase prior to said torque phase comprising:

increasing torque on the second clutch to a prefill torque.

11. A dual clutch transmission as described in claim 10 , wherein said preparation phase further comprises:

torque balancing the first clutch and the second clutch, wherein the torque on the first clutch combined with the torque on the second clutch approximates an engine torque.

12. A dual clutch transmission as described in claim 10 , wherein said prefill torque comprises a plate-touch-point torque.

13. A dual clutch transmission as described in claim 9 , wherein said shift logic is further configured to:

implement a post phase comprising:

increasing torque on the second clutch until it matches the target clutch torque; and

decreasing torque on the first clutch until the first clutch disconnects.

14. A dual clutch transmission as described in claim 13 , wherein the post phase comprises:

generating a torque command loop from the launch/creep controller;

continuously reading the torque command loop to update the target clutch torque; and

continuously adjusting torque on the second clutch to match the updated target clutch torque.

15. A dual clutch transmission as described in claim 9 , wherein said shift logic is in communication with a clutch temperature signal, said shift logic implementing said torque phase in response to said clutch temperature signal indicating an overheating transmission.

16. A dual clutch transmission as described in claim 9 , wherein said shift logic is in communication with a gear selection signal, said shift logic implementing said torque phase in response to said gear selection signal indicating a wrong gear selection.

17. A dual clutch transmission as described in claim 13 , wherein said first clutch and said second clutch remain unlocked during said post phase.

18. A system for operating a dual clutch transmission, including a launch/creep controller and a clutch control assembly including a shift logic, the clutch control assembly configured to:

read a torque command from the launch/creep controller using the shift logic, the torque command including a target clutch torque;

engage a preparation phase comprised of:

increasing torque on an on-coming clutch to a prefill torque;

engage a torque phase comprising:

transferring torque between an off-going clutch and said on-coming clutch by simultaneously decreasing the off-going clutch torque and increasing the on-coming clutch torque, wherein said off-going clutch and said on-coming clutch are both in a slipping state that maintains the target clutch torque during the transfer.

19. A system as described in claim 18 , wherein said clutch control assembly is further configured to:

implement a post phase comprising:

increasing torque on the on-coming clutch until it matches the target clutch torque; and

decreasing torque on the off-going clutch until the off-going clutch disconnects.

20. A system as described in claim 19 , wherein the post phase further comprises:

generating a torque command loop from the launch/creep controller;

continuously reading the torque command loop to update the target clutch torque; and

continuously adjusting torque on the on-coming clutch to match the updated target clutch torque.