US-12623649-B2 - Trailer connection status determination and sharing

US12623649B2US 12623649 B2US12623649 B2US 12623649B2US-12623649-B2

Abstract

Systems and methods carried out in a truck (TW) configured to be coupled to a trailer (TR), wherein a trailer connection status (CST) is determined by a pneumatic line test performed on a test pneumatic line arranged to pneumatically couple the trailer to the truck, the method comprising determining a line test circumstantial criterion, such criterion allowing or not a pneumatic line test to be performed, performing the pneumatic line test, whenever the test circumstantial criterion allows it, and updating therefrom the trailer connection status (CST), from a result of step b— and/or as time passes by, wherein the line test circumstantial criterion comprises at least a first condition representative of an air pressure prevailing in the pneumatic line below a predefined test threshold, a second condition representative of a presence, and/or activity of a driver of the truck in the truck's cabin.

Inventors

Lionel FARRES
Christophe Long

Assignees

VOLVO TRUCK CORPORATION

Dates

Publication Date: 20260512
Application Date: 20191216

Claims (14)

1 . A method carried out in a truck configured to be coupled to a trailer, wherein a trailer connection status is determined by a pneumatic line test performed on a pneumatic line arranged to pneumatically couple the trailer to the truck, the method comprising: determining a line test circumstantial criterion, such line test circumstantial criterion determining whether or not a pneumatic line test is to be performed, performing the pneumatic line test when allowed by the line test circumstantial criterion, and updating the trailer connection status, from a result of the performing the pneumatic line test and/or as time passes, the trailer connection status supplemented by a confidence index, which decreases over time unless refreshed or reset by an updating event, the confidence index being frozen as long as a presence of a driver in a cabin of the truck is determined, wherein the line test circumstantial criterion comprises at least a first condition representative of an air pressure prevailing in the pneumatic line below a predefined test threshold, a second condition representative of a presence of the driver in the cabin of the truck, and a third condition representative of the confidence index being less than a predefined confidence threshold, wherein the pneumatic line test is performed while the second condition representative of a presence of the driver in the cabin of the truck is met.
2 . The method of claim 1 , wherein the second condition representative of a presence of the driver of the truck in the cabin includes relying on a maneuver performed by the driver in the cabin of the truck.
3 . The method of claim 1 , wherein the confidence index exhibits a value between a maximum value and a minimum value, and wherein the confidence index is reset to the maximum value whenever the pneumatic line is inflated or whenever the truck is determined to be in driving conditions.
4 . The method of claim 1 , wherein the line test circumstantial criterion comprises a fourth condition representative of an air pressure prevailing in an air reservoir.
5 . The method of claim 1 , wherein the pneumatic line test is done by a temporary inflation of the pneumatic line, and an outcome of the pneumatic line test is inferred from a pressure profile versus time acquired in response to the temporary inflation.
6 . The method of claim 1 , wherein the pneumatic line is a trailer air pressure supply line.
7 . The method of claim 6 , wherein when the pneumatic line test is positive, representative of a trailer actually pneumatically coupled, the supply of the trailer air pressure supply line is continued and maintained as long as required by a trailer management function.
8 . The method of claim 1 , wherein the method further comprises: propagating the trailer connection status through a truck bus.
9 . A system comprising a parking brake unit having a control unit, the system being installed in a truck configured to be coupled to a trailer, wherein the control unit is configured to determine a trailer connection status, indicating whether the trailer is coupled or uncoupled, from at least a pneumatic line test performed on at least a pneumatic line arranged to pneumatically couple the trailer to the truck, wherein the control unit is configured to: determine a line test circumstantial criterion, such line test circumstantial criterion determining whether or not a pneumatic line test is to be performed, perform the pneumatic line test, when allowed by the line test circumstantial criterion, and update the trailer connection status, from a result of the performed pneumatic line test and/or as time passes, the trailer connection status supplemented by a confidence index, which decreases over time unless refreshed or reset by an updating event, the confidence index being frozen as long as a presence of a driver in a cabin of the truck is determined, wherein the line test circumstantial criterion comprises at least a first condition representative of an air pressure prevailing in the pneumatic line below a predefined test threshold, a second condition representative of a presence of the driver in the cabin of the truck, and a third condition representative of the confidence index being less than a predefined confidence threshold, wherein the pneumatic line test is performed while the second condition representative of a presence of the driver in the cabin of the truck is met.
10 . The system of claim 9 , wherein the control unit is further configured to handle a confidence index that supplements the trailer connection status, the confidence index is caused to decrease over time unless refreshed or reset by an updating event, and wherein the line test circumstantial criterion further comprises at least a third condition representative of the confidence index being less than a predefined confidence threshold.
11 . The system of claim 9 , wherein the system further comprises a gearbox gear lever/control, a park brake knob, and a trailer supply knob arranged to determine the second condition representative of a presence of the driver of the truck in the cabin.
12 . The system of claim 9 , wherein the system further comprises a driver seat occupancy sensor and/or a drowsiness surveillance camera arranged to determine the second condition representative of a presence of driver of the truck in the cabin.
13 . The system of claim 9 , further comprising a pressure sensor arranged on the trailer supply line.
14 . A truck comprising the system of claim 9 .

Description

This application is a 35 USC 371 national phase filing of International Application No. PCT/EP2019/085421, filed Dec. 16, 2019, the disclosure of which is incorporated herein by reference in its entirety. FIELD OF THE DISCLOSURE The present disclosure relates to methods and systems to determine connection status of pneumatic lines of a trailer that can be coupled to a towing vehicle. The connection status, namely coupled or uncoupled, is determined by a pneumatic test procedure. BACKGROUND OF THE DISCLOSURE A semi-trailer combination comprises a truck (otherwise called ‘tractor unit’) and a trailer. Often, however not mandatory in the sense of the present disclosure, such trailer has no front axle, the front portion of the trailer can be detachably coupled to a mechanism called “fifth wheel” of the tractor unit. The truck comprises a powertrain, a pneumatic supply system, a braking system, and a lot of other onboard systems. Between the truck and a trailer, there are provided an electrical coupling arrangement and a pneumatic coupling arrangement. The present disclosure will mainly discuss the pneumatic coupling arrangement, and the coupled or uncoupled status of the pneumatic coupling. The pneumatic coupling arrangement comprises a pressure supply line, having a red color code in the art and a service brake line having a blue color code in the art. The red color pressure supply line supplies the park brake spring loaded cylinders of the trailer. When no air pressure is supplied to the red pressure supply line, the springs of the spring loaded cylinders apply a braking effort to the trailers wheels. By contrast, when air pressure is supplied to the red pressure supply line, the springs of the spring loaded cylinders of the trailer are pushed back and the braking effort is released. In this context, it is important to know whether there is a trailer coupled to the truck or no trailer, since the behavior of the truck is very different between a truck-only configuration and a semi-trailer combination configuration. The trailer connection status (coupled or uncoupled) can be determined mechanically or electrically; however, this requires additional material like one or more sensor. The present disclosure considers the case when the trailer connection status (coupled or uncoupled) is determined by using at least a pneumatic line. An ad hoc pneumatic test procedure allows to test the line using an already provided pressure sensor, thereby avoiding using additional sensing device. SUMMARY OF THE DISCLOSURE According to one aspect of the present disclosure, it is disclosed a method carried out in a truck (TW) configured to be coupled to a trailer (TR), wherein a trailer connection status (i.e. coupled or uncoupled) is determined by at least a pneumatic line test performed on at least one test pneumatic line (41,42) arranged to pneumatically couple the trailer to the truck, the method comprising: a—determine a line test circumstantial criterion, such criterion allowing or not a pneumatic line test to be performed,b—perform the pneumatic line test, whenever the test circumstantial criterion allows it,c—update the trailer connection status, from a result of step b- and/or as time passes by, wherein the line test circumstantial criterion comprise at least a first condition representative of an air pressure prevailing in the pneumatic line (41,42) below a predefined test threshold, a second condition representative of a presence and/or activity of a driver of the truck in the truck's cabin. The term “pneumatic line test” should be understood as a method for generating an air pressure pulse in a pneumatic line and analyzing a pressure response in a timely manner, i.e. deducing, from a curve of pressure against time, aeraulic characteristic of the line. From such aeraulic characteristic of the line, it is determined whether the trailer is actually coupled to the truck or not (i.e. the trailer connection status, pneumatically wise). Advantageously, it is contemplated to have a looped method, i.e. step a- to c— are repeated as long or often as necessary. Advantageously, the pneumatic line test is performed when the driver is inside the cabin, and therefore we avoid performing the test when the driver might be in the course of practicing the coupling maneuver at the back of the cabin. It shall be understood that the pulse test occurrence can be surprising for someone standing just in the vicinity of the glad hand couplings. Therefore, performing the line test according the promoted conditions eliminates the risk of surprising the driver and the risk of fall and this solution thus enhances overall safety. Also, the line test procedure is not performed whenever the test line is already inflated. The trailer connection status may be a simple binary information or a binary information complemented by a confidence index that will be discussed later. We note that a reliable trailer connection status can be useful to other entities