Automated systems and methods for parking commercial vehicles

Abstract

A system for automatically parking a commercial vehicle includes a service braking system having at least one brake valve, a brake controller for controlling the service braking system, and an advanced driver assistance system (ADAS) controller. The ADAS controller communicates with the brake controller and requests activation of the foot brake of the commercial vehicle until the vehicle comes to a stop. In response to the ADAS controller's request to activate the service brake, the brake controller determines that the commercial vehicle should remain stationary and activates at least one brake valve to release system pressure, mechanically parking the vehicle.

Description

Background Technology

[0001] This application relates to a commercial vehicle equipped with an advanced driver assistance system and an electronically controlled service braking system, and a method for parking such a vehicle. Commercial vehicles are typically equipped with electronically controlled braking systems that provide anti-lock braking, traction, and stability control during service braking. Commercial vehicles are also increasingly equipped with advanced driver assistance systems (ADAS), which provide adaptive cruise control and collision mitigation functions. ADAS can actuate the service brakes without driver input. However, most commercial vehicles still have pneumatically operated parking brake systems that must be manually engaged and disengaged.

[0002] ADAS communicates with the electronically controlled braking system to use the service brake to decelerate the vehicle in certain situations. However, ADAS can bring the vehicle to a stop and release the service brake before the driver has full control of the vehicle. In these situations, the vehicle may need to remain stationary. Therefore, those skilled in the art continue to research and develop in the field of service and parking brake systems. Summary of the Invention

[0003] According to one embodiment, a system for automatically parking a commercial vehicle includes a service braking system having at least one brake valve, a brake controller for controlling the service braking system, and an advanced driver assistance system (ADAS) controller. The ADAS controller communicates with the brake controller and requests activation of the foot brake of the commercial vehicle until the vehicle comes to a stop. In response to the ADAS controller's request to activate the service brake, the brake controller determines that the commercial vehicle should remain stationary and activates at least one brake valve to release system pressure, mechanically parking the vehicle.

[0004] In another embodiment, a method for automatically parking a commercial vehicle includes sending a message from an advanced driver assistance system (ADAS) controller to the brake controller requesting activation of the service brake until the commercial vehicle comes to a stop. The method also includes determining that the commercial vehicle should remain stationary and activating a brake valve to release the parking brake actuator, thereby mechanically parking the commercial vehicle. Attached Figure Description

[0005] Figure 1 This is a schematic diagram of a braking system.

[0006] Figure 2 This is a method for implementing an automatic parking system according to an example of the present invention.

[0007] Figure 3 This is a method for implementing an automatic parking system according to a second example of the present invention. Detailed Implementation

[0008] Reference Figure 1 The diagram illustrates a pneumatic braking system 10 for a commercial vehicle. The braking system 10 includes six wheel ends 12a, 12b, 12c, 12d, 12e, and 12f, but may include more or fewer wheel ends depending on the vehicle configuration. In this example, each wheel end 12a, 12b, 12c, and 12d includes a service brake actuator 14a, 14b, 14c, and 14d for converting air pressure into longitudinal motion to actuate a friction brake. The friction brake may be a drum brake or a pneumatic disc brake. The service brake is actuated when the driver presses the brake pedal 16 or when an automated system on the vehicle is requested.

[0009] Wheel ends 12e and 12f include parking brake actuators 18a and 18b. Parking brake actuators 18a and 18b perform both service brake and parking brake functions. Parking brake actuators 18a and 18b include a parking brake spring, which must be compressed by air pressure when the vehicle is to be released from parking. When the air pressure in the system is lower than a predetermined pressure, also known as the parking brake activation pressure, the parking brake spring will mechanically engage and prevent vehicle movement. The air used to actuate the service brake and release the parking brake is sourced from air reservoirs 44a and 44b.

[0010] The braking system 10 includes a brake controller 30. The brake controller 30 has control logic 31 for receiving signals from sensors such as a yaw rate / accelerometer 24, pressure sensors 42a, 42b, and wheel speed sensors 20a, 20b, 20c, 20d. The control logic 31 performs braking functions such as anti-lock braking, stability control, and traction control by directly transmitting electronic control signals to brake control valves 34a, 34b. In one example, brake control valves 34a, 34b are traction control valves 36a, 36b and regulating valves 38a, 38b, 38c, 38d. Traction control valves 36a, 36b are pneumatically connected to air reservoirs 44a, 44b. In another example, brake control valves 34a, 34b are electro-pneumatic brake (EBS) valves. Brake control valves 34a, 34b can also be a combination of solenoid valves and relay valves.

[0011] Control logic 31 also communicates with engine controller 40 on serial communication bus 28 to de-throttle the engine, thereby helping to slow down the vehicle.

[0012] The braking system 10 includes an Advanced Driver Assistance System (ADAS) controller 22, which has control logic 23 for receiving signals from sensors 26, which may be radar or cameras or both. The control logic 23 performs functions such as lane keeping, adaptive cruise control, and collision mitigation by communicating with the brake controller 30 and the engine controller 40 via a serial communication bus 28 or other means.

[0013] When the ADAS controller 22 determines that braking intervention is necessary to avoid a collision, for example, the ADAS controller 22 sends a control message to the brake controller 30, which then activates the service brake upon request. In some cases, the ADAS controller 22 determines that the vehicle must decelerate or even come to a complete stop. Once the vehicle has come to a complete stop, the brake controller 30 may release the service brake if there are no further instructions from the ADAS controller 22. This action of releasing the service brake via the brake controller 30 may cause the vehicle to move unintentionally and slowly if the driver does not keep his foot on the brake pedal 16 or the accelerator pedal (not shown) to continue driving the vehicle.

[0014] In one example, at the end of the automatic operation of the ADAS controller 22, the system of the present invention will detect via pressure sensors 42a, 42b that the driver is not placing his foot on the brake pedal 16 and initiate the parking brake sequence of the present invention. In another example, the brake controller 30 detects that the driver's foot is not on the brake pedal 16 and is not on the accelerator pedal either. Alternatively, the driver may place his foot on the brake pedal 16, but the brake controller 30 determines that insufficient driving braking force is not being applied due to the vehicle beginning to move slowly. The slow movement of the vehicle can be determined by receiving a wheel speed greater than zero from sensors 14a, 14b, 14c, 14d, 14e, 14f.

[0015] In another example, the brake controller 30 detects that the vehicle is stationary due to the action of the ADAS controller 22 by receiving zero wheel speeds from sensors 14a, 14b, 14c, 14d, 14e, and 14f. In another example, the brake controller 30 can determine that the vehicle is stationary by receiving information from sensor 26. In yet another example, the brake controller 30 can determine that the vehicle should remain stationary after the ADAS controller 22 has completed its action because the driver is not visible in the driver-facing camera (not shown).

[0016] The braking system 10 does not include an automatic parking brake controller, so the parking brake must still be mechanically applied and released by the action of the brake controller 30.

[0017] Therefore, a system for automatically parking a commercial vehicle includes a service braking system having at least one brake valve, a brake controller for controlling the service braking system, and an Advanced Driver Assistance System (ADAS) controller. The ADAS controller can communicate with the brake controller and request activation of the commercial vehicle's foot brake until the vehicle comes to a stop. In response to the ADAS controller's request to activate the service brake, the brake controller determines that the commercial vehicle should remain stationary and activates at least one brake valve to release system pressure, mechanically parking the vehicle.

[0018] refer to Figure 2 For commercial vehicles without an automatic parking brake system, the first method 50 for automatic parking begins at step 52. In step 54, ADAS control logic 23 determines whether the vehicle must be stopped to safely complete the automatic action. If the required automatic braking action is temporary and does not stop the vehicle, or if system 10 determines that the driver has full control of the vehicle via brake pedal 16 or accelerator pedal, method 50 returns to step 52.

[0019] Otherwise, method 50 continues to step 56. ADAS controller 22 will communicate with brake controller 30, while brake controller 30 determines whether the vehicle needs parking brake intervention to keep the vehicle stationary.

[0020] In step 56, once it is determined that the vehicle must remain stationary (e.g., the driver does not place his foot on brake pedal 16), brake controller 30 activates brake valves 34a and 34b. In one example, the exhaust solenoid valves of traction relay valve 36a and regulators 38a and 38b are actuated together to create a pathway for air supply from the source, air tanks 44a and 44b to the atmosphere. In another example, both traction relay valves 36a and 36b and all exhaust solenoid valves of regulators 38a, 38b, 38c, and 38d may be actuated simultaneously.

[0021] During activation, brake controller 30 determines whether the pressure in air reservoirs 44a, 44b is less than or equal to a predetermined pressure, as shown in step 58. Brake controller 30 may measure the pressure directly from a pressure sensor (not shown) or receive the pressure on serial communication bus 28. In one example, the predetermined pressure for actuating the parking brake is between approximately 60 psi and approximately 80 psi. If the air pressure in the air reservoir is greater than or equal to the predetermined pressure, method 50 returns to step 56 to continue actuating brake valves 34a, 34b.

[0022] Once the air pressure in the air tanks 44a and 44b is less than the predetermined pressure, the parking brake actuators 18a and 18b will apply the parking spring, thereby using the parking brake to keep the vehicle stationary, as shown in step 60.

[0023] The vehicle will remain parked until the system pressure in the gas tanks 44a and 44b increases above the second predetermined pressure and the driver manually releases the parking brake. In one example, the second predetermined pressure is above approximately 80 psi.

[0024] refer to Figure 3 For commercial vehicles without an automatic parking brake system, the second method 70 for automatic parking begins at step 72. In step 74, ADAS control logic 23 determines whether the vehicle must be stopped to safely complete the automatic intervention. If the required automatic braking action is temporary and does not stop the vehicle, method 70 returns to step 72.

[0025] Otherwise, method 70 continues to step 76. The ADAS controller 22 will communicate with the brake controller 30 and the engine controller 40 via the serial communication bus 28 or other devices. The brake controller 30 determines whether the vehicle requires parking brake intervention to keep the vehicle stationary.

[0026] In step 76, the cycle counter in the brake controller control logic 31 is set to zero. The brake controller 30 will then activate brake valves 34a and 34b in step 78. In one example, the exhaust solenoid valves of traction relay valve 36a and regulators 38a and 38b are actuated together to create an air supply path to the atmosphere. In another example, each of the traction relay valves 36a and 36b and all the exhaust solenoid valves of regulators 38a, 38b, 38c, and 38d can be actuated simultaneously. Activation is maintained until the end of a predetermined time, as in step 80. The predetermined time will vary based on the commercial vehicle pneumatic system configuration. However, the predetermined time can be between approximately one second and approximately fifteen seconds. At the end of the predetermined time, in step 82, the cycle counter in control logic 31 is incremented by 1.

[0027] In step 84, the cycle counter is compared with a predetermined number of cycles. In one example, the predetermined number of cycles is five cycles. One cycle is approximately one second. If the cycle counter is less than the predetermined number of cycles, method 70 returns to step 78 to reactivate brake valves 34a and 34b. If the cycle counter equals the predetermined number of cycles, method 70 continues to step 86, where the vehicle is mechanically parked. The predetermined time and predetermined number of cycles can be adjusted depending on the vehicle type, as it is known that a certain amount of time is required to reduce system pressure to mechanically actuate the brakes. It is not necessary to use method 70 to measure the pressure in air tanks 44a and 44b.

[0028] Methods 50 and 70 can both be interrupted by the driver's actions, such as pressing the accelerator pedal or providing sufficient force by pressing the driving brake pedal.

[0029] Therefore, a method for automatic parking of a commercial vehicle includes transmitting a message from an advanced driver assistance system (ADAS) controller to a brake controller requesting activation of the service brake until the commercial vehicle comes to a stop. The method also includes determining that the commercial vehicle should remain stationary and activating a brake valve to release the parking brake actuator, thereby mechanically parking the commercial vehicle.

[0030] While the invention has been described by way of exemplary processes and system components, and various processes and components have been described in detail, the applicant does not intend to limit the scope of the appended claims to or in any way restrict it to such details. Other modifications will also be readily apparent to those skilled in the art. Therefore, the invention is not, in its broadest sense, limited to the specific details, implementations, or illustrative examples shown and described. Thus, deviations from these details are permissible without departing from the spirit or scope of the applicant's overall inventive concept.

Claims

1. A system for automatically parking a commercial vehicle, comprising: a service brake system having at least one brake valve; a brake controller for controlling the service brake system; and an advanced driver assistance system controller in communication with the brake controller; wherein the advanced driver assistance system controller requests activation of the service brakes of the commercial vehicle until the vehicle is stationary, and wherein the brake controller, in response to the advanced driver assistance system controller requesting activation of the service brakes, determines that the commercial vehicle should remain stationary and activates the at least one brake valve to release system pressure from a parking brake actuator to mechanically park the vehicle, including cyclically activating the brake valve for a predetermined amount of time until a predetermined number of cycles is completed, wherein the predetermined number of cycles correlates to the system pressure being less than a parking brake activation pressure.

2. The system of claim 1, wherein, the brake valve is a combination of a traction relay valve and a modulating valve.

3. The system of claim 1, wherein, the parking brake activation pressure is between 60 psi and 80 psi.

4. The system of claim 1, wherein, the predetermined time period is between one second and fifteen seconds.

5. A method for automatically parking a commercial vehicle, comprising: sending a message from an advanced driver assistance system controller to a brake controller requesting activation of the service brakes until the commercial vehicle is stationary; determining that the commercial vehicle should remain stationary; and activating a brake valve to release system pressure from a parking brake actuator to mechanically park the commercial vehicle, including cyclically activating the brake valve for a predetermined amount of time until a predetermined number of cycles is completed, wherein the predetermined number of cycles correlates to the system pressure being less than a parking brake activation pressure.

6. The method of claim 5, further comprising: determining whether the system pressure is less than a predetermined pressure and continuing to activate the brake valve until the system pressure is less than the predetermined pressure.

7. The method of claim 5 or 6, wherein, the predetermined number of cycles is five cycles.

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