Control system for travel in a platoon

• US 9,423,794 B2
• Filed: 05/30/2011
• Issued: 08/23/2016
• Est. Priority Date: 05/31/2010
• Status: Active Grant

• Current Assignee: Volvo Car Corporation (AB Volvo)
• Original Assignee: Volvo Car Corporation (AB Volvo)
• Inventors: Lind, Henrik, Ekmark, Jonas
• Primary Examiner(s): Olszewski, John R
• Assistant Examiner(s): Foster, Gerrad A
• Application Number:
  US13/700,318
• Publication Number:
  US 20130211624A1
• Time in Patent Office: 1,912 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G01S 2013/9325 for inter-vehicle distance regulation, e.g. navigating in platoons
• CPC Class Codes: G05D 1/021 specially adapted to land vehicles
• CPC Class Codes: G05D 1/0278 using satellite positioning signals, e.g. GPS
• CPC Class Codes: G05D 1/0293 Convoy travelling
• CPC Class Codes: G05D 1/0295 by at least one leading vehicle of the fleet
• CPC Class Codes: G08G 1/22 Platooning, i.e. convoy of communicating vehicles

Abstract

The present invention relates to a control system for travel in a platoon (1), the platoon comprising a lead vehicle (L) and one or more following vehicles (F₁, F₂, . . . , F_i-1, F_i, . . . , F_n) automatically following the lead vehicle, the lead vehicle controlling the movement of the following vehicles, each of the following vehicles and the lead vehicle comprising communication means (10, 12), wherein the control system comprises a common time base, which allows a control command proposing an action to be communicated from the lead vehicle (L) to at least one of the following vehicles (F₁, F₂, . . . , F_i-1, F_i, . . . , F_n) in advance of a control point (t_c). The invention further relates to the use of a common time base in a platoon and to a method to control travelling in a platoon.

Claims

1. A control system for travel in a platoon, said platoon comprising a lead vehicle and one or more following vehicles automatically following the lead vehicle, said lead vehicle controlling the movement of said following vehicles, each of said following vehicles and said lead vehicle comprising communication means, wherein said control system comprising a common time base, wherein a control command is communicated from said lead vehicle to at least one of said one or more following vehicles in advance of a control point of time, the control command entails an action to be executed by the one or more following vehicles at the control point in time, the common time base is based on time signals from an external clock where the time signals are received by the lead vehicle and the one or more following vehicles simultaneously, wherein if the time signals from the external clock cannot be received, then the common time base is based on a last time signal received from the external clock.

2. The control system according to claim 1, wherein the common time base has a precision of at least 10 ms.

3. The control system according to claim 1, wherein a time gap between two vehicles of said platoon is less than 0.6 s.

4. The control system according to claim 1, wherein, in case of signals from said external clock being temporarily undeceivable, a time base of an individual vehicle of said platoon is based on the last signal received from said external clock and/or on a time signal sent from said lead vehicle.

5. The control system according to claim 1, wherein said control command is adapted to compensate for dynamic properties of said at least one following vehicle and/or time delays within said platoon.

6. The control system according to claim 1, wherein said proposed action comprises an action expressed as a state control over time for said following vehicle.

7. The control system according to claim 1, wherein said following vehicle proposes to said lead vehicle a possible limited state action instead of said proposed action according to said control command sent from said lead vehicle.

8. The control system according to claim 1, wherein the control systems further comprises a negotiation, which is used when a candidate following vehicle wants to connect to said platoon, said negotiation comprising sending of boundaries for state control of said candidate following vehicle, and wherein said candidate following vehicle is refused to connect to said platoon, if said candidate following vehicle has a too limited state control capability.

15. The control system according to claim 1, wherein the common time base has a precision of at least 1 ms.

16. The control system according to claim 1, wherein the common time base has a precision of at least 100 μ

s.

17. The control system according to claim 1, wherein said vehicles prepare one or more actions in advance of the control point of time.

9. A use of a common time base in a platoon for controlling travelling in the platoon, the platoon comprising a lead vehicle and one or more following vehicles automatically following the lead vehicle, said lead vehicle controlling the movement of said following vehicles, each of said following vehicles and said lead vehicle comprising communication means, wherein a common time base allows a control command to be communicated from said lead vehicle to at least one of said one or more following vehicles in advance of a control point of time, the control command entails an action to be executed by the one or more following vehicles at the control point in time, the common time base is based on time signals from an external clock where the time signals are received by the lead vehicle and the one or more following vehicles simultaneously, wherein if the time signals from the external clock cannot be received, then the common time base is based on a last time signal received from the external clock.

10. A method for controlling travelling in a platoon, said platoon comprising a lead vehicle and one or more following vehicles automatically following the lead vehicle, said lead vehicle controlling the movement of said following vehicles, each of said following vehicles and said lead vehicle comprising communication means, wherein said method comprising the steps of

(a) establishing a common time base,

(b) transmitting a control command from said lead vehicle to at least one of said one or more following vehicles in advance of a control point of time, the control command entails an action to be executed to be executed by the one or more following vehicles at the control point in time, the common time base is based on time signals from an external clock where the time signals are received by the lead vehicle and the one or more following vehicles simultaneously, wherein if the time signals from the external clock cannot be received, then the common time base is based on a last time signal received from the external clock.

11. The method of claim 10 further comprising the step of:

(c) said at least one of said following vehicles acknowledging the receipt of said control command to the lead vehicle;

and the optional step of;

(d) said lead vehicle sending an execute demand.

12. The method of claim 10 further comprising the step of:

(e) said at least one of said following vehicles communicating a message to said lead vehicle that said following vehicle is able or unable to carry out said proposed action according to said control command.

13. The method of claim 12, in the case able was communicated, said method further comprising the step:

(f) the lead vehicle transmitting an execute command based on step b).

14. The method of claim 12, in the case unable was communicated, said method further comprising the step:

(g) said at least one of said following vehicles communicating to said lead vehicle a possible limited state action;

and the optional step of;

(h) the method returning to step b) and said lead vehicle transmitting a new control command based on said limited state action, or alternatively said lead vehicle releasing said platoon.

18. The method of claim 10, wherein said vehicles prepare one or more actions in advance of the control point of time.