Traction control method for a tracked vehicle
View Patent ↗The present invention provides a traction control method for a tracked vehicle such as a military tank. The method includes calculating a track proportionality factor and a vehicle proportionality factor based on predefined attributes of the tracked vehicle. A minimum turn radius of the tracked vehicle is calculated based on the velocity of the tracked vehicle, the maximum coefficient of friction between the tracks of the tracked vehicle and the ground (0.7), and gravitational acceleration (9.80665 m/s2). A sprocket rotational speed is calculated based on the pitch diameter of the tracked vehicle sprockets and the velocity of the tracked vehicle. Based on the preceding calculations, the method of the present invention calculates a required track speed differential configured to turn the tracked vehicle at the minimum turn radius. If a commanded turn radius is less than the minimum turn radius, the track speed differential of the tracked vehicle is limited to the required track speed differential to prevent the tracked vehicle from slipping.
1. A traction control method for a tracked vehicle comprising:
calculating a minimum turn radius of the tracked vehicle at which the tracked vehicle does not slip using a maximum coefficient of friction between tracks of the vehicle and ground;
calculating a required track speed differential configured to turn the tracked vehicle at the minimum turn radius;
determining if a commanded turn radius is less than the minimum turn radius; and
limiting the track speed differential of the tracked vehicle by selectively transferring more power to at least one of a first track and a second track to achieve the required track speed differential if the commanded turn radius is less than the minimum turn radius such that the tracked vehicle does not slip;
wherein said calculating a required track speed differential includes determining a track proportionality factor α and a vehicle proportionality factor β, and the vehicle proportionality factor β is calculated from the track proportionality factor α according to an equation
β
=
(
0.664
α
-
0.212
)
2
.
2. The traction control method of claim 1 , wherein said calculating a required track speed differential includes determining a relationship between a sprocket rotational speed and a vehicle speed of the tracked vehicle.
3. The traction control method of claim 1 , wherein said calculating a required track speed differential includes determining a sprocket rotational speed.
4. The traction control method of claim 1 , further comprising executing the commanded turn radius if the commanded turn radius is greater than or equal to the minimum turn radius.
5. The traction control method of claim 1 , further comprising measuring a track length of the tracked vehicle.
6. The traction control method of claim 1 , further comprising measuring a track center distance of the tracked vehicle.
7. A traction control method for a tracked vehicle comprising:
determining a track proportionality factor α;
determining a vehicle proportionality factor β using said track proportionality factor according to an equation
β
=
(
0.664
α
-
0.212
)
2
;
calculating a minimum turn radius of the tracked vehicle at which the tracked vehicle does not slip using a maximum coefficient of friction between tracks of the vehicle and ground;
calculating a required track speed differential using said vehicle proportionality factor β and said minimum turn radius, said required track speed differential being configured to turn the tracked vehicle at the minimum turn radius;
determining if a commanded turn radius is less than the minimum turn radius; and
limiting the track speed differential of the tracked vehicle by selectively transferring more power to at least one of a first track and a second track to achieve the required track speed differential if the commanded turn radius is less than the minimum turn radius such that the tracked vehicle does not slip.
8. The fraction control method of claim 7 , wherein said calculating a required track speed differential includes determining a relationship between a sprocket rotational speed and a vehicle speed of the tracked vehicle.
9. The traction control method of claim 7 , wherein said calculating a required track speed differential includes determining a sprocket rotational speed.
10. The fraction control method of claim 7 , further comprising executing the commanded turn radius if the commanded turn radius is greater than or equal to the minimum turn radius.
11. The traction control method of claim 7 , further comprising measuring a track length of the tracked vehicle.
12. The fraction control method of claim 7 , further comprising measuring a track center distance of the tracked vehicle.
13. A traction control method for a tracked vehicle comprising:
determining a track proportionality factor α;
determining a vehicle proportionality factor β using the track proportionality factor according to an equation
β
=
(
0.664
α
-
0.212
)
2
;
calculating a minimum turn radius of the tracked vehicle at which the tracked vehicle does not slip using a maximum coefficient of friction between tracks of the vehicle and ground;
determining a sprocket rotational speed;
calculating a required track speed differential using the vehicle proportionality factor β, the minimum turn radius, and the sprocket rotational speed, said required track speed differential being configured to turn the tracked vehicle at the minimum turn radius;
determining if a commanded turn radius is less than the minimum turn radius;
executing the commanded turn radius if the commanded turn radius is greater than or equal to the minimum turn radius; and
limiting the track speed differential of the tracked vehicle by selectively transferring more power to at least one of a first track and a second track to achieve the required track speed differential if the commanded turn radius is less than the minimum turn radius such that the tracked vehicle does not slip.
14. The traction control method of claim 13 , further comprising measuring a track length of the tracked vehicle.
15. The fraction control method of claim 13 , further comprising measuring a track center distance of the tracked vehicle.