Abstract:
A computer-implemented system and method for operating mobile automated workstations in a workspace including a workpiece is disclosed. A computer device defines an
   exclusionary volume having an outer exclusionary surface at least partially surrounding a mobile   workstation that is operably disposed in the workspace. The computer device receives data from   at least one sensor and determines the location of the workstation and humans within the workspace based on the data. The computer device activates an indicator and alters the motion   of the workstation after detection of a human breaching the exclusionary volume or exclusionary   surface.

Description:
FIELD OF INVENTION 
       [0001]    The present disclosure concerns systems and methods for automatic masking and spray coating of workpieces. In particular, the present disclosure concerns coordinated, robotically controlled sprayed coating applicators and coating masks for applying coating such as paints to workpieces. 
       BACKGROUND 
       [0002]    Automatic robotic control of paint sprayers and other forms of applicators has improved the precision and repeatability of the application of paints and other coating materials. Under certain circumstances, masking is required to achieve the desired coating of a workpiece. For example, masking can be required when only certain portions of a workpiece require coating. In another example, such masking can be required when multiple types of coating are applied over one but where portions of underlying coating remain exposed, or for example where coatings materials are applied to adjacent areas of a workpiece, delineated by a sharp line. Such masking can further be required on multiple duplicate workpieces, such as can be required during mass production of particular workpieces. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]    In the accompanying drawings, structures and methods are illustrated that, together with the detailed description provided below, describe aspects of a system and method for dynamic synchronized coating and masking. It will be noted that a single component may be designed as multiple components or that multiple components may be designed as a single component. 
           [0004]    Further, in the accompanying drawings and description that follow, like parts are indicated throughout the drawings and written description with the same reference numerals, respectively. The figures are not drawn to scale and the proportions of certain parts have been exaggerated for convenience of illustration. 
           [0005]      FIG. 1  illustrates an overhead schematic view of a coating system  100 . 
           [0006]      FIG. 2  illustrates an alternate partial schematic view of coating system  100 . 
           [0007]      FIGS. 3-6  illustrate partial schematic views of coating system  100  and coated workpieces  124 . 
           [0008]      FIG. 7  illustrates steps of a method  700  of coating a workpiece  124 . 
       
    
    
     DETAILED DESCRIPTION 
       [0009]    With reference to  FIG. 1 , a partial perspective view of a coating system  100  is shown according to one aspect of the present teachings. The coating system  100  includes coating applicator robot  102  and masking robot  104 . Each of the coating applicator robot  102  and masking robot  104  has a base  106 , an arm  108  and a wrist  110 . 
         [0010]    The coating applicator robot  102  and masking robot  104  are both articulated robots having 6 degrees of freedom. It should be noted that robots having less than or more than six degrees of freedom can be implemented according to the present teachings. Additional degrees of freedom, such as 7, 8, 9 or more, are possible by, for example, including additional joints with the robot. Fewer degrees of freedom can offer less flexibility relative to robots having 6 degrees of freedom. For example, a robot having 5 or 4 degrees of freedom can be implemented where 6 degrees of freedom are not required due to, for example, the shape of the workpiece not requiring complicated movement of one of the coating applicator robot  102  and masking robot  104 . In addition to articulated robots  102 ,  104 , other forms of programmable manipulators can also be implemented as one or both of robots  102 ,  104  according to the present teachings. Available manipulators include but are not limited to linear-type robots and delta-type robots. 
         [0011]    The coating applicator robot  102  has a coating applicator  112  mounted to a coating applicator bracket  114  which is in turn secured to wrist  110  of coating applicator robot. The applicator  112  has a spray pattern  116  that is rotationally asymmetric about the direction of spraying and that having an elongated pattern. In other cases, the spray pattern  116  can be rotationally symmetric about the direction of spraying. The present teachings can also be implemented with applicators  112  having other different spray patterns  116 . 
         [0012]    The coating applicator robot  102  has a vision bracket  118  mounted to its wrist  110 . The vision bracket  118  secures a camera  120  and a lamp  122  to the robot. The camera  120  can be used to locate detectable reference points on objects such as workpieces  124  or masks  126   a - 126   e  and thereby check the position of the applicator  112  relative to such objects. The lamp  122  improves visibility. 
         [0013]    The masking robot  104  selectively mounts one of the masks  126   a - 126   e  found in magazine  128  by releasing any of the masks  126   a - 126   e  that may be held by the automatic tool changer  130 , and then coupling the empty tool changer  130  to the bracket  132   a - 132   e  of one of the masks  126   a - 126   e.  Once coupled to the tool changer  130 , the chosen mask  126   a  is secured to the masking robot  104  and can be manipulated such that the mask opening  134   a  can be selectively moved relative to the workpiece  124 . It should be noted that the masks  126   a - 126   e  need not be limited to masks with holes such as holes  134   a  and  134   b,  but also can include masks with outer edges that shield the workpiece  112  from coating. 
         [0014]    Both the coating applicator robot  102  and the masking robot  104  are connected to a controller  136   a,    136   b  through physical connections  138   a,    138   b.  While physical connections are shown, wireless connections can also be implemented according to the present disclosure. The controllers  136   a,    136   b  can include, for example, a central processing unit that executes computer-readable instructions stored on a non-transient medium and a power supply for the individual robots  102 ,  104 . According to other aspects of the present teachings, the illustrated robots  102 ,  104  can be connected to a single controller that provides the functionality of the two individual controllers  136   a,    136   b  illustrated in  FIG. 1 . According to still other aspects of the present teachings, one or more controllers  136   a,    136   b  can be implemented with the robots  102 ,  104 . In one example, one controller  136   a,    136   b  can be connected to robots  102 ,  104 . According to yet other aspects of the present teachings, redundant controllers  136   a,    136   b  can be connected to one or more of the robots  102 ,  104 . 
         [0015]    The controllers  136   a,    136   b  can include, for example, a central processing unit (“CPU”), non-transient computer storage media such as random access memory (“RAM”) and hard drive storage that can include one or more solid state and magnetic hard drives, for examples. The CPU can execute instructions stored on the non-transient computer storage media, such as one or both of the RAM and storage. The instructions written on one or both of the RAM and storage are written in a suitable computer-readable programming language such as the C programming language, or a programming language written for use with robots, such as the RAPID programming code made available by ABB, Inc. In addition, planning and programming of automated processes can be performed by use of software such as RobotStudio® which permits loading of three-dimensional models of the workpiece (e.g., CAD representations of the workpiece), into RobotStudio® and programming and simulating the robot processes within RobotStudio®. 
         [0016]    According to one aspect of the present teachings, upon execution of instructions stored on, for example, the RAM or storage by the CPU, the CPU provides signals to at least one of the robots  102 ,  104  that causes to the respective robots  102 ,  104  to move and dispense coating as in the case of the coating applicator robot  102 , or to move the mask  126   a - 126   e  secured to the masking robot  104 . Instructions can be input into controllers  136   a,    136   b  with an input/output device such as a keyboard, touchscreen, mouse, microphone or other device. Instructions can be input as, for example and not limited to, programming code or by inputting a travel path and speed of the applicator  112  or masks  126   a - 126   e.  The controllers  136   a,    136   b  can also include instructions regarding selection, releasing and securing of masks  126   a - 126   e  and instructions regarding the flow rate of the coating, spray patterns or speed of movement of the respective robots  102 ,  104 . 
         [0017]    The controllers  136   a,    136   b  can be connected to one another through connection  140 , which can allow the controllers  136   a,    136   b  to coordinate the movement of the respective robots  102 ,  104  during the coating process. The connection  140  can be an Ethernet connection, or other connection allowing communication between the controllers  136   a,    136   b.  It should be noted that wireless connections can also be implemented instead of or in addition to physical connection  140 . It should be noted that the aspects of controllers  136   a,    136   b  described herein can be distributed, such as by providing computing resources and memory through one or more remote computer workstation, and providing a local interface such as a client computer interface or handheld device that communicates with the workstation through a communication connection such as a wireless connection or suitable cabling. 
         [0018]    The magazine  128  includes a cleaning station  142  that includes brushes  144 . The masks  126   a - 126   e  can be inserted into the station  142  after their use during a coating process according to the present teachings. The masks  126   a - 126   e  can be agitated within the station  142 , which can contain a cleaning solvent, by the masking robot  104 . Once cleaned, the masks  126   a - 126   e  can be returned to magazine  128 . 
         [0019]    While the illustrated workpiece is a piece of sheet metal, various structures can serve as workpieces  124 . Examples of such structures include but are not limited to automotive vehicle components, aircraft wings and fuselages, windmill turbine blades, rockets, and large and small structures having complex 3-dimensional surfaces. With reference to  FIG. 2 , which omits mask magazine  128  for clarity, the workpiece is held stationary on rack  144 . Other forms of mountings can be implemented according to the present disclosure. For example, a robot can hold workpiece  124  in position to apply coating. In another example, workpieces can be placed on a moving conveyor, which would require the robots  102 ,  104  to move in a manner consistent with the motion of the workpiece  124  on a conveyor. As can be seen in  FIG. 2 , the mask  126   a  is relatively thin, and according to one aspect of the present teachings is made of a rigid material such as plastic or metal such that the form of the holes such as holes  134   a  and  134   b  does not change due to flexing or deformation of the mask  126   a - 126   e.    
         [0020]    Various forms of coatings can be applied to workpieces  124  according to the present teachings, including primers and paints, for example automotive and industrial paints and primers. Other materials can be applied, such as liquid adhesives that require precise application. In another non-limiting example, liquid masking materials can be precisely applied according to the present teachings which can serve as a mask for other painting or coating processes to be performed subsequently. 
         [0021]      FIGS. 3 through 6  illustrate various example coordinated movements of the robots  102 ,  104  and the corresponding results of coating a workpiece according to the present teachings. In  FIGS. 3 through 6 , the robots&#39; bases  106  and arms  108  are omitted for clarity. In  FIG. 3 , the mask  126   a,  which has a rectangular mask opening  134   a,  is held still relative to the workpiece while the applicator  112  is moved in direction  300  over the mask  134   a.  The resulting pattern  302  deposited on workpiece  124  is a rectangle matching the shape of the hole  134   a.    
         [0022]    With reference to  FIG. 4 , the mask  126   a  and the applicator  112  are moved in a synchronized manner along similar paths involving translational and rotational motion of the mask  126   a  and applicator  112 . The mask  126   a  is moved along L-shaped path  400  and the applicator  112  is moved along L-shaped path  402 , resulting in an L-shaped pattern  404  of coating material deposited on workpiece  124 . In this way, application of the present teachings can result in coating being deposited in a form having a different shape than the hole  134   a  in the mask  126   a  used in the coating process. 
         [0023]    With reference to  FIG. 5 , the applicator  112  moves along a linear path  500  opposite in direction and greater in speed than the motion of the mask  126   a  along linear path  502 . The resulting pattern  504  that is rectangular like hole  134   a  but having a set of shorter sides due to the opposite motion between path  500  and path  502 . With reference to  FIG. 6 , the applicator  112  moves along linear path  600  with a greater speed than the mask  126   a  which travels along linear path  602  parallel to path  600 . The resulting pattern  604  is a rectangular shape having a set of sides longer than that of hole  134   a.    
         [0024]    With reference to  FIG. 7 , method  700  includes mounting a selected mask  126   a - 126   e  to a masking robot  104  in step  702 . Step  702  can be preceded by unmounting any mask  126   a - 126   e  or other end effector mounted to the tool changer  130 . In step  704 , the selected mask  126   a - 126   e  is moved to a predetermined position relative to the workpiece. In step  706 , an applicator  112  is moved to a predetermined position relative to the workpiece. In step  708 , the selected mask  126   a - 126   e  is positioned between the applicator  112  and the workpiece  124 . In step  710 , applicator  112  dispenses coating through or past the mask  126   a - 126   e  and onto the workpiece  124 . It should be noted that the mask  126   a - 126   e  need not be limited to masks with holes, but also can include masks with outer edges that define where coating is intercepted by the mask  126   a - 126   e.    
         [0025]    During step  710 , a portion of the coating material dispensed by applicator  112  will come into contact with the selected mask  126   a - 126   e.  Also during step  710 , the selected mask  126   a - 126   e  can undertake coordinated movement with the applicator  112  wherein the selected mask  126   a - 126   e  remains positioned between the workpiece  124  and applicator  112  while one or both of the selected mask  126   a - 126   e  and applicator  112  undertake motion relative to the workpiece  124 . Either one or both of applicator  112  or the selected mask  126   a - 126   e  can undertake coordinated motion relative to workpiece  124  during step  710 . For example, the applicator  112  can remain motionless relative to the workpiece  124  while the selected mask  126   a - 126   e  undertakes motion relative to the workpiece  124  while remaining between the workpiece  124  and applicator. Conversely, applicator  112  can be in motion while the selected mask  126   a - 126   e  remains motionless. In another example, both the applicator  112  and selected mask  126   a - 126   e  undertake motion during step  710 . 
         [0026]    In step  712 , the selected mask  126   a - 126   e  is cleaned. For example, the selected mask  126   a - 126   e  can be inserted into the cleaning station  142  at which point the mask  126   a - 126   e  is agitated to release any accumulated coating and then subsequently returned to the magazine  128 . The steps of method  700  can be carried out with, for example, system  100  where instructions for executing the steps of method  700  are written on non-transient computer readable media on controllers  136   a,    136   b.    
         [0027]    For the purposes of this disclosure and unless otherwise specified, “a” or “an” means “one or more.” To the extent that the term “includes” or “including” is used in the specification or the claims, it is intended to be inclusive in a manner similar to the term “comprising” as that term is interpreted when employed as a transitional word in a claim. Furthermore, to the extent that the term “or” is employed (e.g., A or B) it is intended to mean “A or B or both.” When the applicants intend to indicate “only A or B but not both” then the term “only A or B but not both” will be employed. Thus, use of the term “or” herein is the inclusive, and not the exclusive use. See, Bryan A. Garner, A Dictionary of Modern Legal Usage 624 (2d. Ed. 1995). Also, to the extent that the terms “in” or “into” are used in the specification or the claims, it is intended to additionally mean “on” or “onto.” As used herein, “about” will be understood by persons of ordinary skill in the art and will vary to some extent depending upon the context in which it is used. If there are uses of the term which are not clear to persons of ordinary skill in the art, given the context in which it is used, “about” will mean up to plus or minus 10% of the particular term. From about A to B is intended to mean from about A to about B, where A and B are the specified values. 
         [0028]    While the present disclosure illustrates various embodiments, and while these embodiments have been described in some detail, it is not the intention of the applicant to restrict or in any way limit the scope of the claimed invention to such detail. Additional advantages and modifications will be apparent to those skilled in the art. Therefore, the invention, in its broader aspects, is not limited to the specific details and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant&#39;s claimed invention. Moreover, the foregoing embodiments are illustrative, and no single feature or element is essential to all possible combinations that may be claimed in this or a later application.