Automatic dig assistance system for a machine

1. A system for controlling an earth moving machine, comprising:

a speed sensor configured to communicate a speed signal indicative of a speed of the machine;

an operator bucket lift command input configured to communicate an operator-input bucket lift command; and

a controller configured to:

receive the speed signal and the operator-input bucket lift command;

determine a torque of the machine;

using the speed signal and the determined torque, determine a controller-generated bucket lift command; and

provide a bucket lift command which is the larger of the operator-input bucket lift command and the controller-generated bucket lift command.

2. The system of claim 1 , further comprising:

a pressure sensor configured to communicate a pressure signal indicative of a pressure on a bucket of the machine, and wherein the controller is further configured to:

receive the pressure signal; and

using the speed signal, the determined torque, and the pressure signal, determine whether a pile encountered by the machine is a full pile.

3. The system of claim 2 , wherein the controller is further configured to:

using at least one of the speed signal, the determined torque, and the pressure signal, determine the time the time it will take the machine to reach a speed of zero; and

using the calculated time, determine whether the pile encountered by the machine is a full pile.

4. The system of claim 1 , further comprising:

an operator bucket tilt command input configured to communicate an operator-input bucket tilt command, and wherein the controller is further configured to:

provide a bucket tilt command which is the smaller of the operator-input bucket tilt command and a predetermined bucket tilt command ceiling value.

5. The system of claim 1 , further comprising:

a bucket height sensor configured to communicate a signal indicative of the height of a bucket of the machine, and wherein the controller is further configured to:

using the signal of the height of the bucket, determine a rate of change of the height of the bucket; and

compare the determined rate of change to the provided bucket lift command.

6. The system of claim 5 , wherein the controller is further configured to:

calculate the difference between the provided bucket lift command and the determined rate of change; and,

if the difference exceeds a predetermined threshold value, disable the provided lift command.

7. The system of claim 1 , further comprising:

a bucket height sensor configured to communicate a signal indicative of a height of a bucket of the machine, and wherein the controller is further configured to:

using the signal indicative of the height of the bucket and the provided lift command, determine whether there is sufficient hydraulic pressure to prevent slip of the machine on a ground surface.

8. The system of claim 7 , wherein the controller is further configured to:

if there is not sufficient hydraulic pressure, limit torque to the machine.

9. The system of claim 1 , further comprising a mechanism for enabling and/or disabling the system.

10. A method for controlling an earth moving machine, comprising:

receiving a speed signal indicative of a speed of the machine;

determining a torque of the machine;

receiving an operator-input bucket lift command;

using the received speed signal and the determined torque, determining a controller-generated bucket lift command; and

providing a bucket lift command which is the larger of the operator-input bucket lift command and the controller-generated bucket lift command.

11. The method of claim 10 , further comprising:

a receiving a pressure signal indicative of the pressure on a bucket of the machine; and

using the speed signal, the determined torque, and the pressure signal, determining whether a pile encountered by the machine is a full pile.

12. The method of claim 11 , further comprising

using at least one of the speed signal, the determined torque, and the pressure signal, determining the time the time it will take the machine to reach a speed of zero; and

using the determined time, determining whether the pile encountered by the machine is a full pile.

13. The method of claim 10 , further comprising:

receiving an operator-input bucket tilt command; and

providing a bucket tilt command which is the smaller of the operator-input bucket tilt command and a predetermined bucket tilt command ceiling value.

14. The method of claim 10 , further comprising:

receiving a signal indicative of a height of a bucket of the machine;

using the signal of the height of the bucket, calculating a rate of change of the height of the bucket of the machine; and

comparing the calculated rate of change to the provided bucket lift command.

15. The method of claim 14 , further comprising:

calculating the difference between the provided bucket lift command and the calculated rate of change; and

if the difference exceeds a predetermined threshold value, disabling the provided lift command.

16. The method of claim 10 , further comprising:

receiving a signal indicative of a height of a bucket of the machine; and

using the signal indicative of the height of the bucket and the provided lift command, determining whether there is sufficient hydraulic pressure to prevent slip of the machine on a ground surface.

17. The system of claim 16 , further comprising:

if there is not sufficient hydraulic pressure, limiting torque to the machine.

18. The system of claim 10 , further comprising activating or deactivating the system.

19. A system for controlling an earth moving machine, comprising:

a speed sensor configured to communicate a speed signal indicative of a speed of the machine;

a pressure sensor configured to communicate a pressure signal indicative of the pressure on a bucket of the machine; and

a controller configured to:

determine a torque of the machine; and

using the speed signal, the determined torque, and the pressure signal, determine whether a pile encountered by the machine is a full pile.

20. The system of claim 19 wherein the controller is further configured to:

using at least one of the speed signal, the determined torque, and the pressure signal, determine the time the time it will take the machine to reach a speed of zero; and

using the determined time, determine whether the pile encountered by the machine is a full pile.