An amt gear shifting optimization control system and method based on a whole vehicle vcu architecture

Abstract

The present application relates to a kind of AMT shift optimization control system and method based on whole vehicle VCU architecture, including whole vehicle control system, transmission control system, engine control system, electronic brake system, automatic emergency brake system and shift control system;Transmission control system, electronic brake system, shift control system and automatic emergency brake system are electrically connected with GW gateway by PCAN bus;Whole vehicle control system and engine control system are electrically connected with GW gateway by ECAN bus;PCAN bus and ECAN bus are electrically connected by whole vehicle control system;Transmission control system judges whether to execute jump shift strategy by judging accelerator, whole vehicle acceleration signal, if executing jump shift, engine brake is called in jump shift, upshift process, brake request torque is sent to engine control system by whole vehicle control system arbitration, shortens the shift speed synchronization time, i.e. shorten the shift interruption time, improves the whole vehicle driving performance, makes the power performance in speed-up process improve and reduces fuel consumption.

Description

Technical Field

[0001] This invention relates to the field of automotive control technology, and in particular to an AMT shift optimization control system and method based on the vehicle's VCU architecture. Background Technology

[0002] The domestic heavy-duty commercial vehicle AMT (Automated Manual Transmission) market has entered a period of rapid growth, while customers are also demanding higher levels of driving comfort. Because heavy-duty commercial vehicles have multiple gears in their mechanical automatic transmissions, with small speed differences between lower gears, gear shifts are frequent. Furthermore, AMTs only have one clutch, causing power interruption with each shift, resulting in a poor driving experience. In the heavy-duty commercial vehicle sector, research is actively underway on vehicle control systems, transmissions, and engine assemblies to shorten power interruption time, reduce power loss, improve shift quality, and enhance overall vehicle economy and performance by improving engine response speed and the torque reduction / recovery slope during gear shifts. However, many AMT commercial vehicles on the market still suffer from the following problems: the small speed differences between low gears in mechanical automatic transmissions, while improving engine response accuracy and the torque reduction / recovery slope during gear shifts, still result in power interruptions due to frequent shifts, leading to poor acceleration performance and fuel economy. Summary of the Invention

[0003] This invention proposes an AMT shift optimization control system and method based on the vehicle VCU architecture. The transmission control system determines whether to execute a skip-gear strategy by comprehensively judging the throttle and vehicle acceleration signals. If skip-gear is executed, engine braking is invoked during the skip-gear and upshift process. Through arbitration by the vehicle control system, the braking request torque is sent to the engine control system, which shortens the shift speed synchronization time, thereby shortening the shift interruption time, improving the overall vehicle driving performance, enhancing the power of the vehicle acceleration process and reducing fuel consumption.

[0004] To address the problems mentioned above in the background section, the present invention is achieved through the following technical solution:

[0005] An AMT shift optimization control system based on a vehicle VCU architecture includes a vehicle control system, a transmission control system, an engine control system, an electronic braking system, an automatic emergency braking system, and a shift control system. The transmission control system, the electronic braking system, the shift control system, and the automatic emergency braking system are electrically connected to a GW gateway via a PCAN bus. The vehicle control system and the engine control system are electrically connected to the GW gateway via an ECAN bus. The PCAN bus and the ECAN bus are electrically connected through the vehicle control system.

[0006] Preferably, the shift control system is used to transmit the gear request signal to the transmission control system and the vehicle control system via the PCAN bus.

[0007] Preferably, the engine control system is used to transmit engine speed and engine coolant temperature signals to the vehicle control system via the ECAN bus.

[0008] Preferably, the vehicle control system is used to transmit engine speed and engine coolant temperature signals to the transmission control system via the PCAN bus.

[0009] Preferably, the electronic braking system is used to transmit acceleration signals and braking signals to the transmission control system.

[0010] Preferably, the transmission control system sends an engine request for positive torque, control mode, and priority signal to the vehicle control system via a TSC1_TE message;

[0011] The transmission control system sends engine braking negative torque, control mode and priority signals to the vehicle control system via TSC1_TER message;

[0012] The electronic braking system sends engine torque request, control mode and priority signals to the vehicle control system via TSC1_EBS messages.

[0013] The automatic emergency braking system sends engine torque request, control mode, and priority signals to the vehicle control system via TSC1_AEB messages. The control modes include no-control mode, torque control / limiting mode, and speed control / limiting mode. In no-control mode, engine torque and speed are not controlled; these are determined by the throttle MAP. Priorities are categorized as highest priority, high priority, medium priority, and low priority. The highest priority is used for situations requiring immediate action from the receiving device to ensure safe vehicle operation. High priority is used for control situations requiring rapid action to ensure safe vehicle operation. Medium priority is used for powertrain control operations related to ensuring stable vehicle operation. Low priority is used to indicate commands requiring powertrain control but also functions that enhance driver comfort.

[0014] Preferably, the vehicle control system performs priority, magnitude verification, limitation, and superposition of torque requests from the transmission control system, the electronic braking system, and the emergency automatic braking system, and after arbitration, sends them to the engine control system via a TSC1_VCU message; the engine control system responds to the engine braking torque requested by the vehicle control system, so that the engine speed is quickly synchronized.

[0015] An AMT shifting optimization method based on the vehicle VCU architecture includes the following steps:

[0016] S1. During vehicle operation, the transmission control system detects that the current gear is inconsistent with the target gear and enters the gear shift scheduling control process;

[0017] S2. The transmission control system 2 comprehensively determines whether to perform a gear skipping based on the current gear, target gear, throttle opening, braking, and vehicle acceleration, and sets a threshold value a for acceleration a. min and a max When the target gear is updated, determine if a min <a<a max If a ≥ a max If a ≤ a min If so, then sequential gear shifting will be performed;

[0018] S3. Enter the gear shift scheduling control state. When the target gear - current gear > 1, execute the gear skip control.

[0019] S4. The transmission control system 2 calculates the engine synchronous speed based on the output shaft speed and the target gear ratio. Engine synchronous speed = output shaft speed × target gear ratio;

[0020] S5. After the engine requested torque and clutch torque are reduced to zero, the shifting process enters the speed adjustment stage. The transmission control system 2 determines that the engine speed is ≥1000rpm and the engine coolant temperature is ≥70℃. Then, it sends the engine control mode as torque control and the torque request as 0 to the vehicle control system 1 through the TSC1_TE message; and sends the engine control mode as torque control and the braking torque as -100% to the vehicle control system 1 through the TSC1_TER message.

[0021] S6. Due to the engine braking torque response delay, in order to avoid jitter when the speed is synchronized, the braking torque should be cleared to zero in advance. After entering the speed adjustment stage, the engine braking torque is maintained for 0.2s. During this process, if the difference between the engine speed and the engine synchronization speed calculated by S4 is less than 350rpm, the braking torque will be cleared to zero immediately.

[0022] S7. The transmission control system 2 sends the engine control mode and braking torque request to the vehicle control system 1. The vehicle control system 1 verifies and compares the functional power requests of throttle, cruise, speed limit, transmission, idle speed boost, electronic braking system 4 and automatic emergency braking system 5. The functional power requests of throttle, cruise, speed limit, transmission, idle speed boost, electronic braking system 4 and automatic emergency braking system 5 are restricted or verified in terms of priority and magnitude in the form of torque, and are superimposed and arbitrated with idle speed adjustment torque and power take-off torque. After arbitration, the engine torque request is sent to the engine control system 3 through TSC1 message.

[0023] Compared with the prior art, the present invention has the following beneficial technical effects:

[0024] The transmission control system determines whether to execute a shift-skip strategy by comprehensively judging the throttle and vehicle acceleration signals. If a shift-skip strategy is executed, engine braking is invoked during the shift-skip and upshift process. The vehicle control system checks, limits, and superimposes the torque requests from the transmission control system, electronic braking system, and emergency automatic braking system in terms of priority and magnitude, and sends them to the engine control system after arbitration. The engine control system responds to the engine braking torque requested by the vehicle control system, so that the engine speed is quickly synchronized. The braking torque request is sent to the engine control system, which shortens the shift speed synchronization time, thereby shortening the shift interruption time, improving the overall vehicle driving performance, enhancing the power of the vehicle acceleration process, and reducing fuel consumption. Attached Figure Description

[0025] Figure 1 This is a network architecture topology diagram of the shift optimization control system of the present invention;

[0026] Figure 2 This is a schematic diagram of the shift optimization control system of the present invention;

[0027] Figure 3 This is a schematic diagram of the shift optimization method of the present invention;

[0028] Figure 4 This is an explanatory diagram of the shifting optimization method of the present invention;

[0029] Explanation of reference numerals in the attached figures

[0030] 1. Vehicle control system; 2. Transmission control system; 3. Engine control system; 4. Electronic braking system; 5. Automatic emergency braking system; 6. Shift control system; 7. PCAN bus; 8. ECAN bus; 9. GW gateway. Detailed Implementation

[0031] Example 1

[0032] like Figures 1-2 As shown, an AMT shift optimization control system based on a vehicle VCU architecture includes a vehicle control system 1, a transmission control system 2, an engine control system 3, an electronic braking system 4, an automatic emergency braking system 5, and a shift control system 6. The transmission control system 2, electronic braking system 4, shift control system 6, and automatic emergency braking system 5 are electrically connected to a GW gateway 9 via a PCAN bus 7. The vehicle control system 1 and engine control system 3 are electrically connected to the GW gateway 9 via an ECAN bus 8. The PCAN bus 7 and ECAN bus 8 are electrically connected through the vehicle control system 1. The vehicle control system 1, located between the ECAN bus 8 and the PCAN bus 7, is used for the coordination and control of the vehicle's powertrain system.

[0033] The shift control system 6 is used to transmit the gear request signal (TC1 message) to the transmission control system 2 and the vehicle control system 1 via the PCAN bus 7.

[0034] The engine control system 3 is used to transmit the engine speed (EEC1 message) and engine coolant temperature signal (ET1 message) to the vehicle control system 1 via the ECAN bus 8.

[0035] The vehicle control system 1 is used to transmit engine speed and engine coolant temperature signals to the transmission control system 2 via the PCAN bus 7.

[0036] The electronic braking system 4 is used to transmit acceleration signals (VDC2 message) and braking signals (EBC1 message) to the transmission control system 2.

[0037] The transmission control system 2 sends the engine request for positive torque, control mode, and priority to the vehicle control system 1 via a TSC1_TE message;

[0038] The transmission control system 2 sends the engine braking negative torque, control mode and priority to the vehicle control system 1 via the TSC1_TER message;

[0039] The electronic braking system 4 sends engine torque request, control mode and priority signals to the vehicle control system 1 via the TSC1_EBS message;

[0040] The Automatic Emergency Braking System 5 sends engine torque request, control mode, and priority signals to the vehicle control system 1 via the TSC1_AEB message. The control modes are: no control mode, torque control / limiting mode, and speed control / limiting mode. In the no control mode, the engine torque and speed are not controlled, and the engine torque and speed are determined by the throttle MAP. The priority is divided into highest priority, high priority, medium priority, and low priority. The highest priority is used for situations where the receiving equipment needs to take immediate action to provide safe vehicle operation. The high priority is used for control situations where rapid action is needed to provide safe vehicle operation. The medium priority is used for powertrain control operations related to ensuring the vehicle is in a stable operating state. The low priority is used to indicate that the relevant command requires powertrain control, but functions that need to improve driver comfort are also needed. The throttle MAP is the accelerator pedal characteristic, which is converted into the torque required by the driver based on the engine speed and throttle opening.

[0041] The vehicle control system 1 performs priority, magnitude verification, limitation, and superposition of torque requests from the transmission control system 2, electronic braking system 4, and automatic emergency braking system 5, and after arbitration, sends them to the engine control system 3 through the message TSC1_VCU; the engine control system 3 responds to the engine braking torque requested by the vehicle control system 1, so that the engine speed is quickly synchronized.

[0042] Example 2

[0043] like Figures 3-4 As shown, an AMT shifting optimization method based on the vehicle VCU architecture includes the following steps:

[0044] S1. During vehicle operation, the transmission control system 2 detects that the current gear is inconsistent with the target gear and enters the gear shift scheduling control process;

[0045] S2. The transmission control system 2 comprehensively determines whether to perform a gear skipping based on the current gear, target gear, throttle opening, braking, and vehicle acceleration, and sets a threshold value a for acceleration a. min and a max When the target gear is updated, determine if a min <a<a max If a ≥ a max If a ≤ a min If so, then sequential gear shifting will be performed;

[0046] S3. Enter the gear shift scheduling control state. When the target gear - current gear > 1, execute the gear skip control.

[0047] S4. The transmission control system 2 calculates the engine synchronous speed based on the output shaft speed (ETC1_Transmission Output ShaftSpeed) and the target gear ratio (ETC2_Transmission Actual Gear Ratio). Engine synchronous speed = output shaft speed × target gear ratio;

[0048] S5. After the engine requested torque and clutch torque decrease to zero, the shifting process enters the speed adjustment stage. The transmission control system 2 determines that the engine speed is ≥1000rpm (which can be calibrated according to the engine model) and the engine coolant temperature is ≥70℃ (which can be calibrated according to the engine model). Then, it sends the engine control mode as torque control and the torque request as 0 to the vehicle control system 1 through the message TSC1_TE; and sends the engine control mode as torque control and the braking torque as -100% to the vehicle control system 1 through the message TSC1_TER; where the braking torque of -100% is the maximum braking torque.

[0049] S6. Due to the engine braking torque response delay, in order to avoid jitter when the speed is synchronized, the braking torque should be cleared to zero in advance. After entering the speed adjustment stage, the engine braking torque is maintained for 0.2s (calibrable). During this process, if the difference between the engine speed (EEC1_Engine Speed) and the engine synchronization speed (Engine Syn Speed) calculated by S4 is less than 350rpm, the braking torque will be cleared to zero immediately.

[0050] S7. The transmission control system 2 sends the engine control mode and braking torque request to the vehicle control system 1. The vehicle control system 1 verifies and compares the functional power requests of throttle, cruise, speed limit, transmission, idle speed boost, electronic braking system 4 and automatic emergency braking system 5. The functional power requests of throttle, cruise, speed limit, transmission, idle speed boost, electronic braking system 4 and automatic emergency braking system 5 are restricted or verified in terms of priority and magnitude in the form of torque, and are superimposed and arbitrated with idle speed adjustment torque and power take-off torque. After arbitration, the engine torque request is sent to the engine control system 3 through TSC1 message.

[0051] The definitions of TSC1_TE, TSC1_TER, TSC1_EBS, TSC1_AEB, TSC1, TC1, EEC1, ET1, VDC2, EBC1 messages, control modes, and priorities are all existing technologies and belong to the message definitions in the J1939 protocol. The J1939 protocol is based on the Controller Area Network (CAN) developed by Robert Bosch GmbH in Germany, achieving a communication rate of up to 250Kbps. It describes a network application of fieldbus for heavy-duty vehicles, including CAN network physical layer definitions, data link layer definitions, application layer definitions, network layer definitions, fault diagnosis, and network management. The SAE J1939 protocol not only specifies transmission types, message structures and their segmentation, and flow checks, but also precisely defines the message content itself. J1939 is the most widely used application layer protocol in commercial vehicles, ships, rail locomotives, agricultural machinery, and large engines.

[0052] Example 3

[0053] The vehicle control system 1 monitors the driving environment information and vehicle operating status in real time. The vehicle test is carried out according to the method in Example 2. The test results are shown in the test table. When the shifting up mode is triggered, the engine braking is activated. The engine speed synchronization time is shortened by 0.3s (22%) and the shifting time is shortened by 0.47s (15.8%), thereby improving the vehicle's economy and power.

[0054] Test table

[0055]

Claims

1. An AMT shift optimization control system based on a vehicle VCU architecture, characterized in that: It includes a vehicle control system (1), a transmission control system (2), an engine control system (3), an electronic braking system (4), an automatic emergency braking system (5), and a shift control system (6); the transmission control system (2), the electronic braking system (4), the shift control system (6), and the automatic emergency braking system (5) are electrically connected to the GW gateway via a PCAN bus (7); the vehicle control system (1) and the engine control system (3) are electrically connected to the GW gateway (9) via an ECAN bus (8); the PCAN bus (7) and the ECAN bus (8) are electrically connected via the vehicle control system (1); The system performs the following steps: S1. During the vehicle's operation, the transmission control system (2) detects that the current gear is inconsistent with the target gear and enters the gear shift scheduling control process; S2. Transmission control system (2) comprehensively judges whether to perform a gear skipping based on the current gear, target gear, throttle opening, braking and vehicle acceleration, and sets the threshold value a of acceleration a. min and a max When the target gear is updated, determine if a min <a<a max If a ≥ a max If a ≤ a min If so, then sequential gear shifting will be performed; S3. Enter the gear shift scheduling control state. When the target gear - current gear > 1, execute the gear skip control. S4. Transmission control system (2) Calculates engine synchronous speed based on output shaft speed and target gear ratio, engine synchronous speed = output shaft speed × target gear ratio; S5. After the engine requested torque and clutch torque are reduced to zero, the shifting process enters the speed adjustment stage. The transmission control system (2) determines that the engine speed is ≥1000rpm and the engine water temperature is ≥70℃. Then, it sends the engine control mode as torque control and the torque request as 0 to the vehicle control system (1) through the TSC1_TE message; and sends the engine control mode as torque control and the braking torque as -100% to the vehicle control system (1) through the TSC1_TER message. S6. Due to the engine braking torque response delay, in order to avoid jitter when the speed is synchronized, the braking torque should be cleared to zero in advance. After entering the speed adjustment stage, the engine braking torque is maintained for 0.2s. During this process, if the difference between the engine speed and the engine synchronization speed calculated by S4 is less than 350rpm, the braking torque will be cleared to zero immediately. S7. The transmission control system (2) sends the engine control mode and braking torque request to the vehicle control system (1). The vehicle control system (1) verifies and compares the power requests for the functions of throttle, cruise, speed limit, transmission, idle speed increase, electronic braking system (4), and automatic emergency braking system (5). The power requests of the transmission, idle speed boost, electronic braking system (4) and automatic emergency braking system (5) are prioritized and limited or verified in the form of torque, and are superimposed and arbitrated with idle speed adjustment torque and power take-off torque. After arbitration, the engine torque request is sent to the engine control system (3) through TSC1 message.

2. The AMT shift optimization control system based on the vehicle VCU architecture according to claim 1, characterized in that, The shift control system (6) is used to transmit the gear request signal to the transmission control system (2) and the vehicle control system (1) via the PCAN bus (7).

3. The AMT shift optimization control system based on the vehicle VCU architecture according to claim 2, characterized in that, The engine control system (3) is used to transmit engine speed and engine coolant temperature signals to the vehicle control system (1) via the ECAN bus (8).

4. The AMT shift optimization control system based on the vehicle VCU architecture according to claim 3, characterized in that, The vehicle control system (1) is used to transmit engine speed and engine coolant temperature signals to the transmission control system (2) via the PCAN bus (7).

5. The AMT shift optimization control system based on the vehicle VCU architecture according to claim 1, characterized in that, The electronic braking system (4) is used to transmit acceleration signals and braking signals to the transmission control system (2).

6. The AMT shift optimization control system based on the vehicle VCU architecture according to claim 1, characterized in that, The transmission control system (2) sends the engine request positive torque, control mode and priority signal to the vehicle control system (1) via TSC1_TE message. The transmission control system (2) sends engine braking negative torque, control mode and priority signal to the vehicle control system (1) via TSC1_TER message. The electronic braking system (4) sends engine request torque, control mode and priority signals to the vehicle control system (1) via TSC1_EBS message. The automatic emergency braking system (5) sends the engine request torque, control mode and priority signal to the vehicle control system (1) through the TSC1_AEB message; the control mode is no control mode, torque control / limiting mode, speed control / limiting mode; the no control mode does not control the engine torque and speed, and the engine torque and speed are determined according to the throttle MAP; The priorities are divided into highest priority, high priority, medium priority, and low priority. The priorities are as follows: the highest priority is for situations where the receiving device needs to take immediate action to provide safe vehicle operation; the high priority is for control situations where rapid action is needed to provide safe vehicle operation; the medium priority is for powertrain control operations related to ensuring the vehicle is in a stable operating state; and the low priority is for functions that indicate relevant commands requiring powertrain control but also need to improve driver comfort.

7. The AMT shift optimization control system based on the vehicle VCU architecture according to claim 1, characterized in that, The vehicle control system (1) performs priority, magnitude verification, limitation and superposition of torque requests from the transmission control system (2), the electronic braking system (4) and the automatic emergency braking system (5), and after arbitration, sends them to the engine control system (3) via a TSC1_VCU message; the engine control system (3) responds to the engine braking torque requested by the vehicle control system (1) to quickly synchronize the engine speed.

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