Control system and method for walking drilling rigs

Abstract

A method for moving a drilling rig includes receiving a selection of a rig walking mode, wherein the rig walking mode corresponds to a direction of movement, determining an angle of orientation for feet of the drilling rig based on the selected rig walking mode, rotating the feet such that the feet are in the angle of orientation, lifting the rig by pushing the feet into a ground, and moving the rig relative to the ground in the direction of movement.

1 . A method for moving a drilling rig, comprising:
 receiving, at a control system, a selection of a rig walking mode from a user via a control device, wherein the rig walking mode corresponds to a direction of movement;   determining, using the control system, an angle of orientation for each foot of a plurality of feet of the drilling rig based on the selected rig walking mode, wherein the angles of orientation are coordinated so as to result in the rig moving in the direction of movement corresponding to the rig walking mode that was selected;   rotating the feet by sending signals from the control system, such that the feet are in the angle of orientation;   lifting the rig by pushing the feet into a ground; and   moving the rig relative to the ground in the direction of movement.   
     
     
         2 . The method of  claim 1 , further comprising receiving a walk command after receiving the selection of the rig walking mode, wherein rotating the feet occurs in response to receiving the walk command. 
     
     
         3 . The method of  claim 1 , wherein rotating the feet comprises:
 receiving a feedback signal from a rotary position sensor coupled to a rotation mechanism configured to rotate one of the feet; and   adjusting a rotation of the one of the feet in response to the feedback signal.   
     
     
         4 . The method of  claim 1 , wherein rotating the feet comprises reducing a rotation speed of the feet prior to reaching the angle of orientation. 
     
     
         5 . The method of  claim 1 , wherein the rig walking mode comprises rotating the drilling rig, and wherein rotating the feet comprises rotating at least one of the feet to a first angle and rotating at least another one of the feet to a second angle, the first and second angles being different by between about 1 degree and about 10 degrees. 
     
     
         6 . The method of  claim 1 , further comprising disabling individual control of the feet by the control device after receiving the selection therefrom, such that the feet are rotated to the angle of orientation without intervention from the user. 
     
     
         7 . A drilling rig system, comprising:
 a substructure;   a plurality of walking pods coupled to the substructure, each of the walking pods comprising a rotating mechanism, a lift mechanism, a travel mechanism, and a foot, wherein the rotating mechanism is configured to rotate the foot relative to the substructure and a ground, the lift mechanism is configured to raise and lower the foot relative to the substructure and the ground, and the travel mechanism is configured to move the foot relative to the substructure and the ground in a horizontal direction; and   a control system in communication with the plurality of walking pods, wherein the control system is configured to:
 receive a selection of a rig walking mode from a user via a control device, wherein the rig walking mode comprises a walking direction; 
 automatically determine an angle of orientation for each foot based on the selected rig walking mode, wherein the angles of orientation are coordinated so as to result in the substructure moving in the walking direction of the rig walking mode that was selected; 
 cause the respective rotating mechanisms to rotate the respective feet, such that each foot of the walking pods is in the angle of orientation that was determined for the respective foot; 
 cause the respective lift mechanisms to lift the substructure by pushing the feet into the ground; and 
 cause the travel mechanisms to move the substructure relative to the feet in the angle of orientation. 
   
     
     
         8 . The drilling system of  claim 7 , wherein the control system comprises a rig controller and a mobile control module, the mobile control module being in communication with the plurality of walking pods via the rig controller. 
     
     
         9 . The drilling system of  claim 7 , wherein the plurality of walking pods each comprise a rotary position sensor configured to provide a feedback signal to the control system representing a rotational position of the foot relative to the substructure. 
     
     
         10 . The drilling system of  claim 9 , wherein at least one of the rotation mechanisms comprises a slew drive, and wherein the rotary position sensor comprises an encoder coupled to the slew drive. 
     
     
         11 . The drilling system of  claim 7 , wherein the control system is configured to decrease a rotation speed of the feet prior to stopping rotation of the feet when the feet are in the orientation. 
     
     
         12 . The drilling system of  claim 11 , wherein the control system is configured to ramp the rotation speed down prior to stopping rotation. 
     
     
         13 . The drilling system of  claim 7 , wherein the travel mechanism comprises a horizontally-positioned hydraulic cylinder that is configured to slide the foot relative to the substructure. 
     
     
         14 . The drilling system of  claim 7 , wherein in at least one rig walking mode, the feet are all positioned at a first angle relative to a centerline of the substructure. 
     
     
         15 . The drilling system of  claim 14 , wherein in at least another rig walking mode, the predetermined orientation for at least one of the feet is a first angle, and the predetermined orientation for at least another one of the feet is a second angle, the first angle being different than the second angle, and wherein the walking direction in the at least one rig walking mode comprises a rotational direction. 
     
     
         16 . The drilling system of  claim 15 , wherein the first angle is between 1 degree and 10 degrees greater than the second angle. 
     
     
         17 . A method for moving a drilling rig, comprising:
 receiving a selection of a rig walking mode, wherein the rig walking mode corresponds to a direction of movement, and wherein the rig walking mode is selected from a plurality of rig walking modes, wherein each of the plurality of rig walking modes is associated with at least one angle of orientation for feet of the drilling rig;   automatically determining, using the control system, a respective angle of orientation for each of the feet of the drilling rig based on the selected rig walking mode, wherein the angles of orientation are coordinated so as to result in the rig moving in the direction of movement corresponding to the rig walking mode that was selected;   rotating the feet such that each of the feet are in the respective angle of orientation;   lifting the rig by pushing the feet into a ground; and   moving the rig relative to the ground in the direction of movement.   
     
     
         18 . The method of  claim 17 , wherein rotating the feet comprises:
 receiving a feedback signal from a rotary position sensor coupled to a rotation mechanism configured to rotate one of the feet; and   adjusting a rotation of the one of the feet in response to the feedback signal.   
     
     
         19 . The method of  claim 17 , wherein the plurality of rig walking modes comprise:
 a first rig walking mode in which the angles of orientation are the same, such that the direction of movement is linear; and   a second rig walking mode in which two of the angles of orientation are different from two others of the angles of orientation, such that the direction of movement is rotary.   
     
     
         20 . The method of  claim 19 , wherein, in the second rig walking mode, the two angles of orientation differ from the two other angles of orientation by between about 1 degree and about 10 degrees.