Patent ID: 7413031

Claim:
A system for controlling a horizontal drilling machine which produces a thrust output in response to a thrust input signal and a rotation output in response to a rotation input signal, comprising: a dynamic control system for the horizontal drilling machine adapted to regulate the thrust input signal and the rotation input signal in response to dynamic user input, the dynamic control system comprising at least one manually operable user input device; a thrust maintenance system adapted to automatically maintain the thrust input signal at a user-selected thrust maintenance level in response to a thrust maintenance signal; a rotation maintenance system adapted to automatically maintain the rotation input signal at a user-selected rotation maintenance level in response to a rotation maintenance signal; a thrust interrupt system adapted to discontinue automatic maintenance of the thrust input signal in response to a thrust interrupt signal; a rotation interrupt system adapted to discontinue automatic maintenance of the rotation input signal in response to a rotation interrupt signal; and a thrust resume system adapted to restore automatic maintenance of the thrust input signal to the previous selected thrust maintenance level in response to a thrust resume signal; wherein the thrust interrupt signal is generated in response to a user manipulation of the at least one manually operable user input device during a drilling operation.