Method and system for preventing rollover of a vehicle train

1. A method for preventing rollover of a vehicle train, the vehicle train including a tractor vehicle and a trailer vehicle, the tractor and trailer vehicles having wheels, the tractor vehicle having a tractor vehicle braking system, the trailer vehicle having a trailer vehicle braking system, the tractor vehicle further having a control system arranged and constructed to automatically actuate at least one of the tractor vehicle braking system and the trailer vehicle braking system when a vehicle train rollover danger is present, the method comprising the steps of receiving in said control system at least one data signal from said trailer vehicle and at least one other data signal from said tractor vehicle, said at least one data signal forming a basis for determining wheel speed of at least one wheel of said trailer vehicle disposed on a side of said trailer vehicle at the inside of a curve when said vehicle train is negotiating said curve and said at least one other data signal forming a basis for determining ground speed of said side of said trailer vehicle, and ascertaining whether a vehicle train rollover danger exists based on said wheel speed and said ground speed,

wherein said at least one data signal includes at least one of (i) an average value of a speed of a wheel on a left side of said trailer vehicle and a speed of a wheel on the right side of said trailer vehicle, and (ii) a difference value of said speeds, and wherein said at least one other data signal includes at least one of a lateral acceleration value, a wheel speed and a steering angle value of said tractor vehicle.

2. The method of claim 1 , further comprising the steps of actuating said trailer vehicle braking system and, based at least in part on at least one of ground speed and wheel speed of said tractor vehicle, measuring brake slip on said at least one wheel of said trailer vehicle disposed on said side of said trailer vehicle at the inside of said curve.

3. The method of claim 2 , wherein a vehicle train rollover danger is recognized when said brake slip reaches a predefined threshold value.

4. The method of claim 1 , wherein said at least one data signal from said trailer vehicle includes an average value of wheel speeds of at least two of said wheels of said trailer vehicle and a difference value of wheel speeds of said at least two of said wheels of said trailer vehicle.

5. The method of claim 1 , wherein said at least one data signal from said trailer vehicle is evaluated in accordance with ISO Standard 11992.

6. The method of claim 1 , further comprising the step of transmitting a test brake-demand signal to said trailer vehicle braking system from said control system and initiating a test braking action to actuate said trailer vehicle braking system such that said at least one wheel of said trailer vehicle disposed on a side of said trailer vehicle at the inside of said curve is acted on by a brake force smaller than a maximum brake force.

7. The method of claim 6 , further comprising the step of determining lateral acceleration of said vehicle train, and wherein said step of transmitting said test brake-demand signal to said trailer vehicle braking system occurs when said lateral acceleration reaches a predefined value.

8. A system for preventing rollover of a vehicle train, the vehicle train including a tractor vehicle and a trailer vehicle, the tractor and trailer vehicles having wheels, the tractor vehicle including a tractor vehicle braking system, the trailer vehicle including a trailer vehicle braking system, the system comprising control means associated with the tractor vehicle arranged and constructed to automatically actuate at least one of the tractor vehicle braking system and the trailer vehicle braking system when a vehicle train rollover danger is present, means for receiving in said control means at least one data signal from said trailer vehicle and at least one other data signal from said tractor vehicle, said at least one data signal forming a basis for determining wheel speed of at least one wheel of said trailer vehicle disposed on a side of said trailer vehicle at the inside of a curve when said vehicle train is negotiating said curve and said at least one other data signal forming a basis for determining ground speed of said side of said trailer vehicle, and means for ascertaining whether a vehicle train rollover danger exists based on said wheel speed and said ground speed

wherein said at least one data signal includes at least one of (i) an average value of a speed of a wheel on a left side of said trailer vehicle and a speed of a wheel on the right side of said trailer vehicle, and (ii) a difference value of said speeds, and wherein said at least one other data signal includes at least one of a lateral acceleration value, a wheel speed and a steering angle value of said tractor vehicle.

9. The system of claim 8 , further comprising means for actuating said trailer vehicle braking system, and means for measuring brake slip on said at least one wheel of said trailer vehicle disposed on said side of said trailer vehicle at the inside of said curve based at least in part on at least one of ground speed and wheel speed of said tractor vehicle.

10. The system of claim 9 , wherein a vehicle train rollover danger is recognized when said brake slip reaches a predefined threshold value.

11. The system of claim 8 , wherein said at least one data signal from said trailer vehicle includes an average value of wheel speeds of at least two of said wheels of said trailer vehicle and a difference value of wheel speeds of said at least two of said wheels of said trailer vehicle.

12. The system of claim 8 , wherein said at least one data signal from said trailer vehicle is evaluated in accordance with ISO Standard 11992.

13. The system of claim 8 , further comprising means associated with said control means for transmitting a test brake-demand signal to said trailer vehicle braking system, and means for initiating a test braking action to actuate said trailer vehicle braking system such that said at least one wheel of said trailer vehicle disposed on a side of said trailer vehicle at the inside of said curve is acted on by a brake force smaller than a maximum brake force.

14. The system of claim 13 , further comprising means for determining lateral acceleration of said vehicle train, and means for transmitting said test brake- demand signal to said trailer vehicle braking system when said lateral acceleration reaches a predefined value.