Coordinated control of steerable attachments

Abstract

Traditionally, for certain grading tasks in which a motor grader is not suitable or available, a grader attachment, with caster wheels and a blade, may be attached to a work machine, such as a skid steer. Such systems have difficulty operating due to lateral forces on the blade. Accordingly, a steerable attachment is disclosed with ground-engaging members (e.g., wheels) that can be steered and/or driven via an attachment electronic control module, which is in communication with a machine electronic control module of the work machine. In particular, attachment electronic control module and machine electronic control module may coordinate the steering of the work machine and steerable attachment, using a feedback loop, to ensure that the steering of the work machine does not exceed the capabilities of the steerable attachment.

What is claimed is: 
     
         1 . A steerable attachment comprising:
 an attachment body, wherein the attachment body comprises a fastening portion, and wherein the fastening portion is configured to attach to a work machine;   a blade connected to the attachment body and configured to flatten a surface;   at least one ground-engaging member;   a steerable axle system connected to the attachment body and configured to steer and rotate the at least one ground-engaging member; and   an attachment electronic control module configured to
 receive one or more steering commands from a machine electronic control module in the work machine, 
 actuate the steerable axle system according to the one or more steering commands, 
 measure a position of the steerable axle system, 
 calculate a steering radius of the steerable axle system based on the measured position, and 
 send the calculated steering radius to the machine electronic control module. 
   
     
     
         2 . The steerable attachment of  claim 1 , wherein the blade is joined to the attachment body along a central axis, and configured to rotate around the central axis. 
     
     
         3 . The steerable attachment of  claim 1 , wherein the steerable axle system comprises at least one all-wheel drive hub, and wherein the at least one ground-engaging member comprises a wheel that is driven by the at least one all-wheel drive hub. 
     
     
         4 . The steerable attachment of  claim 3 , wherein the at least one all-wheel drive hub comprises at least two all-wheel drive hubs, wherein the steerable axle system comprises a rod extending between the at least two all-wheel drive hubs, and wherein each end of the rod is attached to a respective one of the at least two all-wheel drive hubs by a respective spindle. 
     
     
         5 . The steerable attachment of  claim 1 , wherein the at least one ground-engaging member comprises at least two wheels, wherein the steerable axle system comprises a tie rod connected between at least two steering arms, and wherein each of the at least two steering arms is connected to a respective one of the at least two wheels. 
     
     
         6 . The steerable attachment of  claim 5 , wherein the steerable axle system comprises at least two steering actuators, and wherein each of the at least two steering actuators is connected to a respective one of the at least two steering arms and configured to extend and retract. 
     
     
         7 . The steerable attachment of  claim 1 , wherein the attachment electronic control module is configured to receive the one or more control parameters via a wired connection through the fastening portion. 
     
     
         8 . The steerable attachment of  claim 1 , wherein the attachment electronic control module is configured to receive the one or more control parameters via wireless communication. 
     
     
         9 . The steerable attachment of  claim 1 , wherein the one or more steering commands comprise one or both of a turn radius or a differential speed between the at least two wheels. 
     
     
         10 . An assembly comprising:
 the work machine; and   the steerable attachment of  claim 1 , attached to the work machine via the fastening portion.   
     
     
         11 . The assembly of  claim 10 , wherein the work machine comprises:
 one or more machine controls; and   a machine electronic control module configured to
 receive a steering control from the one or more machine controls, 
 send the one or more steering commands to the attachment electronic control module based on the steering control, 
 receive a steering radius from the attachment electronic control module, and 
 match a steering radius of the work machine to the received steering radius. 
   
     
     
         12 . The assembly of  claim 11 , wherein the work machine further comprises a pair of tracks, and wherein the steering radius of the work machine is a steering radius of the pair of tracks. 
     
     
         13 . The assembly of  claim 10 , wherein the work machine is a skid steer. 
     
     
         14 . The assembly of  claim 10 , wherein the work machine comprises a pair of loader arms, wherein the fastening portion comprises a pair of engagement members, and wherein each of the pair of engagement members is configured to connect to a respective one of the pair of loader arms. 
     
     
         15 . A steerable attachment comprising:
 an attachment body, wherein the attachment body comprises a fastening portion, and wherein the fastening portion is configured to attach to a work machine;   a blade connected to the attachment body and configured to flatten a surface, wherein the blade is joined to the attachment body along a central axis, and configured to rotate around the central axis;   at least one ground-engaging member;   a steerable axle system connected to the attachment body and configured to steer and rotate the at least one ground-engaging member, wherein the steerable axle system comprises at least one all-wheel drive hub, and wherein the at least one ground-engaging member is driven by the at least all-wheel drive hub; and   an attachment electronic control module configured to
 receive one or more steering commands from a machine electronic control module in the work machine, 
 actuate the steerable axle system according to the one or more steering commands, 
 measure a position of the steerable axle system, 
 calculate a steering radius of the steerable axle system based on the measured position, and 
 send the calculated steering radius to the machine electronic control module. 
   
     
     
         16 . The steerable attachment of  claim 15 , wherein the at least one all-wheel drive hub comprises at least two all-wheel drive hubs, wherein the steerable axle system comprises a rod extending between the at least two all-wheel drive hubs, and wherein each end of the rod is attached to a respective one of the at least two all-wheel drive hubs by a respective spindle. 
     
     
         17 . The steerable attachment of  claim 15 , wherein the at least one ground-engaging member comprises at least two ground-engaging members, wherein the steerable axle system comprises a tie rod connected between at least two steering arms, wherein each of the at least two steering arms is connected to a respective one of the at least two ground-engaging members, wherein the steerable axle system comprises at least two steering actuators, and wherein each of the at least two steering actuators is connected to a respective one of the at least two steering arms and configured to extend and retract. 
     
     
         18 . A method of controlling an steerable attachment that is attached to a work machine, the method comprising:
 by a machine electronic control module in the work machine,
 receiving a steering control from one or more machine controls in the work machine, 
 sending one or more steering commands to an attachment electronic control module in the steerable attachment based on the steering control, 
 receiving a steering radius from the attachment electronic control module, and 
 matching a steering radius of the work machine to the received steering radius; and by the attachment electronic control module in the steerable attachment, 
 receiving the one or more steering commands from the machine electronic control module, 
 actuating a steerable axle system of the steerable attachment according to the one or more steering commands, 
 measuring a position of the steerable axle system, 
 calculating a steering radius of the steerable axle system based on the measured position, and 
 sending the calculated steering radius to the machine electronic control module. 
   
     
     
         19 . The method of  claim 18 , wherein the one or more steering commands comprise one or both of a turn radius or a differential speed between at least two wheels of the steerable attachment. 
     
     
         20 . The method of  claim 18 , wherein the work machine comprises a pair of tracks, and wherein the steering radius of the work machine is a steering radius of the pair of tracks.