Patent Publication Number: US-2023141674-A1

Title: System and method for preventing debris buildup in vacuum sensor lines

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims priority to U.S. Patent Application Ser. No. 63/278,295 filed on Nov. 11, 2021, the entire disclosure of which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to the handling of parcels within a sorting or similar facility. 
     In a sorting facility for parcels, various parcels are unloaded from trucks or other vehicles at unloading locations, sorted, and then loaded onto trucks or other vehicles at loading locations for delivery to the intended recipients. Thus, within the sorting facility, there is often a complex system of conveyors and equipment that facilitates transport and sorting of the parcels within the facility. One such piece of equipment useful for sorting the various parcels is a robot singulator including a robotic framework (comprised of one or more arms) and an end effector, such as a vacuum-based end effector, that is mounted to the distal end of the robotic framework and configured to engage parcels. In this regard, a number of different robot singulators exist in the art, one of which is disclosed in commonly assigned U.S. Pat. Nos. 10,646,898 and 10,994,309, which are incorporated herein by reference. 
     To engage and transport parcels, vacuum-based end effectors commonly include one or more vacuum cups that provide a suction force sufficient to grasp and hold a target parcel when placed in fluid communication with a vacuum source. To detect pneumatic engagement with a parcel, each vacuum cup of the end effector can be operably connected to a vacuum sensor that is configured to provide vacuum pressure feedback indicative of whether the vacuum cup has pneumatically engaged with the parcel, as disclosed, for example, in commonly assigned U.S. Patent Application Publication No. 2020/0262069, which is incorporated herein by reference. 
     To operably connect the vacuum cups of the end effector and corresponding vacuum sensors, the end effector will typically include one or more ports, with each port corresponding to one of the vacuum cups of the end effector. A vacuum sensor line is then provided for each port to connect the port with a vacuum sensor, thereby placing the vacuum sensor in fluid communication with the vacuum cup corresponding to the port. As a flow of air is drawn through a vacuum cup, a certain degree of air is also drawn through the vacuum sensor line connecting the vacuum cup to the vacuum sensor, which is subsequently measured by the vacuum sensor. Such inflow of air can, however, also draw in and introduce dust and other debris into the vacuum sensor line and/or vacuum sensor. Over time, a buildup of dust or other debris can adversely affect the accuracy of the feedback provided by the vacuum sensor. 
     Accordingly, there is a need for systems and methods which prevent buildup of dust or other debris within vacuum sensor lines utilized with a vacuum-based end effector. 
     SUMMARY OF THE INVENTION 
     The present invention is directed to a system and method for preventing debris buildup in vacuum sensor lines. 
     An exemplary system for preventing debris buildup in vacuum sensor lines (or debris evacuation system) made in accordance with the present invention includes: a manifold, including a positive air pressure source and a controller; and one or more positive air pressure lines, with each positive air pressure line having a proximal end in fluid communication with the manifold and a distal end configured to be placed in fluid communication with a vacuum sensor line, that, in turn, is in fluid communication with a vacuum-based end effector of a robot singulator or similar robot. The controller is operably connected to the positive air pressure source, such that the controller can selectively activate the positive air pressure source to emit a positive flow of air that can be directed into the one or more positive air pressure lines. Positive air pressure directed into the one or more positive air pressure lines is subsequently directed into any vacuum sensor lines in fluid communication therewith, thus evacuating dust or other debris accumulated within such vacuum sensor lines. The debris evacuation system can thus be utilized in this way and on a regular basis to prevent the buildup of debris within vacuum sensor lines in fluid communication with the positive air pressure source, thus, in turn, reducing the risk of such debris adversely affecting the readings obtained by any vacuum sensors corresponding to such vacuum sensor lines. 
     In some embodiments, the debris evacuation system further includes one or more connectors, where each connector is configured to place a vacuum sensor line in fluid communication with a positive air pressure line of the debris evacuation system and to place such vacuum sensor line in fluid communication with a vacuum sensor. In some embodiments, each connector of the debris evacuation system includes a first end that is configured to engage a proximal end of a vacuum sensor line, a second end that is configured to engage a distal end of a positive air pressure line of the debris evacuation system, and a third end configured to engage a port of the manifold that is in fluid communication with a vacuum sensor. 
     In some embodiments, the debris evacuation system further includes one or more filters, where each filter is configured to be placed in fluid communication with a vacuum sensor line associated with a vacuum-based end effector, which, in some cases, may also be in fluid communication with a positive air pressure line of the debris evacuation system. 
     In some embodiments, the manifold further includes one or more valves operably connected to the controller and configured to transition between an open and a closed configuration. In such embodiments, each valve is in fluid communication with the positive air pressure source and the positive air pressure line(s), such that the valve can be transitioned between the open configuration and the closed configuration based on instructions communicated by the controller to regulate airflow from the positive air pressure source to the positive air pressure line(s) with which it is in fluid communication. 
     The controller of the manifold can be programmed to selectively activate the positive air pressure source at predetermined intervals and/or following events which may promote the entry of debris into vacuum sensor lines in fluid communication with the one or more positive air pressure lines. For instance, in some embodiments, the controller can be configured to activate the positive air pressure source to emit a positive flow of air simultaneously with the release of a parcel from the vacuum-based end effector. 
     In some embodiments, the manifold may further include a vacuum source to which one or more vacuum lines in fluid communication with the vacuum-based end effector can be placed in fluid communication with. In one such embodiment, the manifold further includes a valve that is configured to transition between a first configuration to permit a negative flow of air to be drawn through the one or more vacuum lines while the vacuum source is activated and a second configuration to permit a positive flow of air emitted from the positive air pressure source to be directed into the one or more vacuum lines. In use, the valve can thus be selectively transitioned from the first configuration to the second configuration and the positive pressure source activated to direct a positive flow of air through the vacuum line(s) to promote the release of (or “blow off”) a parcel engaged with the vacuum-based end effector and/or clear the vacuum line(s) of debris present therein. In some implementations, a positive flow of air may be directed into both the vacuum sensor line(s) and vacuum line(s) simultaneously to prevent debris expelled from vacuum line(s) from being pushed back into the vacuum sensor line(s). 
     The debris evacuation system can be utilized in combination with a robot singulator or similar robot with a vacuum-based end effector and one or more vacuum sensor lines. 
     A method for preventing debris build up in one or more vacuum sensor lines is also disclosed herein. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a side view of a parcel handling system, including an exemplary system for preventing debris buildup in vacuum sensor lines (or debris evacuation system) made in accordance with the present invention; 
         FIG.  2    is a partial perspective view of the exemplary debris evacuation system of  FIG.  1   ; 
         FIG.  3    is another partial perspective view of the exemplary debris evacuation system of  FIG.  1   ; 
         FIG.  4    is a partial side view of certain components of the parcel handling system and the exemplary debris evacuation system of  FIG.  1   ; and 
         FIG.  5    is a schematic diagram of a manifold of the exemplary debris evacuation system of  FIG.  1   . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is a system and method for preventing debris buildup in vacuum sensor lines. 
       FIG.  1    is a side view of a parcel handling system  10 , including an exemplary system for preventing debris buildup in vacuum sensor lines (or debris evacuation system)  20  made in accordance with the present invention. In this example, the parcel handling system  10  is for the singulation of parcels, and the debris evacuation system  20  is operably connected to a robot singulator  30 . Furthermore, because the exemplary debris evacuation system  20  is a component of the parcel handling system  10 , it may also be characterized as a “subsystem.” 
       FIGS.  2  and  3    are partial perspective views of the exemplary debris evacuation system  20 , and  FIG.  5    is a schematic diagram of a manifold of the exemplary debris evacuation system  20 . 
     Referring now to  FIGS.  1 - 3  and  5   , the parcel handling system  10  generally includes: a robot singulator (or robot)  30  with a vacuum-based end effector (or end effector)  34  for engaging parcels with one or more vacuum cups  35   a,    35   b,    35   c,    35   d  mounted on the end effector  34 ; one or more vacuum lines  33   a,    33   b,    33   c,    33   d,  which place the one or more vacuum cups  35   a,    35   b,    35   c,    35   d  in fluid communication with a vacuum source  25  that is configured to draw air through the vacuum lines  33   a,    33   b,    33   c,    33   d;  one or more vacuum sensor lines  24   a,    24   b,    24   c,    24   d,  which place the end effector  34  in fluid communication with one or more vacuum sensors  21   a,    21   b,    21   c,    21   d;  and the debris evacuation system  20 . The debris evacuation system  20  includes: a manifold  22 , including a positive air pressure source  23  and a controller  40 ; and one or more positive air pressure lines  28   a,    28   b.  In this example, the debris evacuation system  20  is described as including only two positive air pressure lines  28   a,    28   b  in fluid communication with two vacuum sensor lines  24   a,    24   b,  but, as should become clear in the description that follows, in most embodiments, it is expected that a positive pressure air pressure line would be associated and in fluid communication with each vacuum sensor line. 
     Referring now to  FIGS.  1 - 3  and  5   , the controller  40  is operably connected to the positive air pressure source  23 , such that the controller  40  can selectively communicate instructions (signals) which activate the positive air pressure source  23  to emit a positive flow of air. Each positive air pressure line  28   a,    28   b  has a proximal end that is in fluid communication with the positive air pressure source  23  and a distal end in fluid communication with one of the one or more vacuum sensor lines  24   a,    24   b.  In this regard, each positive air pressure line  28   a,    28   b  thus   defines a pathway through which the positive flow of air emitted by the positive air pressure source  23  can travel from manifold  22  into the vacuum sensor line  24   a,    24   b  with which the positive air pressure line  28   a,    28   b  is in fluid communication. The positive air entering the vacuum sensor line  24   a,    24   b  forces dust or other debris out of the vacuum sensor line  24   a,    24   b.  The controller  40  can be programmed to selectively activate the positive air pressure source  23  at predetermined time intervals while the debris evacuation system  20  is in use and/or following events which may promote the entry of debris into the one or more vacuum sensor lines  24   a,    24   b,  such as the end effector  34  engaging and releasing a target parcel. In this way, the debris evacuation system  20  of the present invention can thus be utilized to prevent the buildup of debris within one or more of the vacuum sensor lines  24   a,    24   b,    24   c,    24   d  of the larger parcel handling system  10 , and the risk of such debris adversely affecting the vacuum sensors  21   a,    21   b,    21   c,    21   d  corresponding to such vacuum sensor lines  24   a,    24   b,    24   c,    24   d.    
       FIG.  4    is a partial side view of the end effector  34  of the robot singulator  30  and a filter  50 , which, in this exemplary embodiment, is also a component of the debris evacuation system  20 . 
     Referring now to  FIGS.  1 - 5   , in this exemplary embodiment, the robot singulator  30  includes the end effector  34  and a robotic framework  32  to which the end effector  34  is mounted. Although not shown, it is appreciated that the robot singulator  30  will also typically include one or more cables, which extend from the robotic framework  32  and/or the end effector  34 , and which are operably connected to various source components, e.g., a power source (not shown) and a signal source (not shown). As noted above, in this exemplary embodiment, the end effector  34  is a vacuum-based end effector and, as such, includes one or more vacuum cups  35   a,    35   b,    35   c,    35   d  for engaging parcels. In this exemplary embodiment, there are four such vacuum cups  35   a,    35   b,    35   c,    35   d:  a first vacuum cup  35   a,  which is placed in fluid communication with the vacuum source  25  via a first vacuum line  33   a;  a second vacuum cup  35   b,  which is placed in fluid communication with the vacuum source  25  via a second vacuum line  33   b;  a third vacuum cup  35   c,  which is placed in fluid communication with the vacuum source  25  via a third vacuum line  33   c;  and a fourth vacuum cup  35   d,  which is placed in fluid communication with the vacuum source  25  via a fourth vacuum line  33   d.  The vacuum source  25  can be selectively activated to provide each vacuum cups  35   a,    35   b,    35   c,    35   d  with a suction force sufficient to engage and hold a parcel as it is transported from one location to another by the robot singulator  30 . As shown in  FIGS.  1  and  4   , the end effector  34  also includes a sensor port  36   a,    36   b,    36   c  (three of which are visible in  FIG.  1   ). Each vacuum sensor port  36   a,    36   b,    36   c  is in fluid communication with the vacuum cup  35   a,    35   b,    35   c,    35   d  to which it corresponds and is configured to connect to a respective vacuum sensor line  24   a,    24   b,    24   c,    24   d,  which, in turn, is in fluid communication with a respective vacuum sensor  21   a,    21   b,    21   c,    21   d  ( FIG.  5   ), as further described below. For the vacuum sensor lines  24   a,    24   b  in fluid communication with a positive air pressure line  28   a,    28   b,  the sensor port  36   a,    36   b  corresponding to the vacuum sensor line  24   a,    24   b  provides an outlet through which debris present in the vacuum sensor line  24   a,    24   b  can be expelled through the vacuum cups  35   a,    35   b  corresponding to the vacuum sensor line  24   a,    24   b.  Suitable end effectors which may be utilized in the present invention include, but are not limited to, those described in U.S. Patent Application Publication No. 2020/0262069 and U.S. Patent Application Publication No. 2021/0221002, both of which are incorporated herein by reference. 
     Referring now to  FIGS.  1 - 4   , the vacuum lines  33   a,    33   b,    33   c,    33   d,  vacuum senor lines  24   a,    24   b,    24   c,    24   d,  and positive air pressure lines  28   a,    28   b  referred to herein are preferably constructed of a flexible vacuum tubing, which is known and commonly utilized within the art. 
     Referring now to  FIGS.  1  and  5   , in this exemplary embodiment, the robotic framework  32  includes a first arm  32   a,  a second arm  32   b,  and a third arm  32   c  that can be selectively activated to move the end effector  34 . The robotic framework  32  thus provides multiple degrees of freedom, thus enabling the robotic framework  32  to be positioned in the manner necessary for the end effector  34  to engage a target parcel. One suitable robot singulator  30  for use in the present invention is a Delta 3 P6 robot manufactured by Schneider Electric and available, for instance, from Advantage Industrial Automation of Duluth, Ga. In some embodiments, the selection of parcels for engagement with the end effector  34 , movement of the respective components of the robotic framework  32 , and actuation of the end effector  34  may be regulated by a vision and control subsystem (not shown), such as that disclosed in commonly assigned U.S. Patent Application Publication No. 2021/0221002, U.S. Patent Application Publication No. 2021/0395023, U.S. Pat. Nos. 10,646,898, and 10,994,309, each of which is incorporated herein by reference. 
     Referring now specifically to  FIG.  5   , in addition to the positive air pressure source  23  and the controller  40 , in this exemplary embodiment, the manifold  22  also includes the vacuum sensors  21   a,    21   b,    21   c,    21   d  (and, in this case, there are four such sensors), and the vacuum source  25  of the parcel handling system  10 . Each vacuum sensor  21   a,    21   b,    21   c,    21   d  corresponds to one of the vacuum cups  35   a,    35   b,    35   c,    35   d  of the end effector  34  and is configured to obtain readings indicative of the pneumatic engagement or non-engagement of the vacuum cup to which it corresponds with a parcel. As shown, each vacuum sensor  21   a,    21   b,    21   c,    21   d  is operably connected to the controller  40 , such that readings obtained by the vacuum sensors  21   a,    21   b,    21   c,    21   d  are communicated to the controller  40  for subsequent processing. The proximity between the positive air pressure source  23  and the vacuum source  25  in this exemplary embodiment within the manifold  22  is advantageous as it permits a single valve  19  to regulate both positive airflow (positive air pressure) into the vacuum sensor lines  24   a,    24   b  in fluid communication with the positive air pressure source  23  and negative airflow (negative air pressure) through the vacuum lines  33   a,    33   b,    33   c,    33   d  in fluid communication with the vacuum source  25 , as further described below. It should be appreciated, however, that, while offering certain advantages and benefits, the proximity of the positive air pressure source  23  and the vacuum source  25  is not critical to the central functionality of the debris evacuation system  20 . Similarly, while the proximity of the vacuum sensors  21   a,    21   b,    21   c,    21   d  to the controller  40  may offer some advantages, the proximity of the vacuum sensors  21   a,    21   b,    21   c,    21   d  to the controller  40  is also not critical to the central functionality of the debris evacuation system  20 . Accordingly, embodiments are contemplated herein in which the vacuum sensors  21   a,    21   b,    21   c,    21   d  and/or the vacuum source  25  are not components of the manifold  22  and are positioned elsewhere within the parcel handling system  10 . 
     Referring still to  FIG.  5   , the controller  40  includes a processor  42  which executes instructions (routines) stored in a memory component  44  or other computer-readable medium to perform the various operations of the controller  40  described herein. Accordingly, it should be appreciated that each operation described herein for the controller  40  corresponds to a set of instructions stored in the memory component  44 , which, when executed by the processor  42 , cause the controller  40  to perform the stated operation, unless otherwise specified. As shown, the controller  40  is operably connected to the positive air pressure source  23  and the vacuum source  25 , such that the controller  40  can communicate instructions (signals) to selectively activate the positive air pressure source  23  to emit a positive flow of air and can communicate instructions (signals) to selectively activate the vacuum source  25  to provide each vacuum cup  35   a,    35   b,    35   c,    35   d  with a suction force sufficient to engage and hold a parcel as it is transported from one location to another. 
     Referring now to  FIGS.  1 - 3  and  5   , the manifold  22  includes a housing  16  in which the components of the manifold  22  are housed. In this exemplary embodiment, the housing  16  is actually comprised of multiple housings located in close proximity to each other. To facilitate the inflow of air to each vacuum sensor  21   a,    21   b,    21   c,    21   d,  in this exemplary embodiment, the manifold  22  includes a vacuum sensor port  27   a,    27   b,    27   c,    27   d  for each vacuum sensor  21   a,    21   b,    21   c,    21   d.  In this exemplary embodiment, each vacuum sensor port  27   a,    27   b,    27   c,    27   d  is defined, at least in part, by the housing  16  of the manifold  22  and is configured to connect and place one of the vacuum sensor lines  24   a,    24   b,    24   c,    24   d  in fluid communication with the vacuum sensor  21   a,    21   b,    21   c,    21   d  to which the vacuum sensor port  27   a,    27   b,    27   c,    27   d  corresponds. Similarly, to facilitate the drawing of air through each vacuum line  33   a,    33   b,    33   c,    33   d,  in this exemplary embodiment, the manifold  22  further includes a vacuum port  31   a,    31   b,    31   c,    31   d  for each of the vacuum lines  33   a,    33   b,    33   c,    33   d.  In this exemplary embodiment, each vacuum port  31   a,    31   b,    31   c,    31   d  is defined, at least in part, by the housing  16  of the manifold  22  and is configured to connect and place one of the vacuum lines  33   a,    33   b,    33   c,    33   d  in fluid communication with the vacuum source  25  and the positive air pressure source  23 , or an intermediate component in fluid communication with the vacuum source  25  and the positive air pressure source  23 , as further described below. 
     Referring still to  FIGS.  1 - 3 , and  5   , in this exemplary embodiment and as noted above, the debris evacuation system  20  includes two positive air pressure lines: a first positive air pressure line  28   a;  and a second positive air pressure line  28   b.  Again, in this example, the debris evacuation system  20  is described as including only two positive air pressure lines  28   a,    28   b  in fluid communication with two vacuum sensor lines  24   a,    24   b,  but, in most embodiments, a positive pressure air pressure line would be associated with and in fluid communication with each vacuum sensor line. The proximal end of the first positive air pressure line  28   a  and the proximal end of the second positive air pressure line  28   b  are each placed in fluid communication with the positive air pressure source  23 . To this end, the manifold  22  also includes a first positive air flow port  29   a  corresponding to the first positive air pressure line  28   a  and a second positive air flow port  29   b  corresponding to the second positive air pressure line  28   b.  In this exemplary embodiment, the first positive air flow port  29   a  and the second positive air flow port  29   b  are each defined, at least in part, by the housing  16  of the manifold  22  and are each configured to place the proximal end of the first positive air pressure line  28   a  and the second positive air pressure line  28   b,  respectively, in fluid communication with the positive air pressure source  23  or an intermediate component that is in fluid communication with the positive air pressure source  23 , such as the first valve  17  and the second valve  18  described below. In alternative embodiments, instead of multiple valves regulating the flow of positive air from the positive air pressure source  23  to the first positive airflow port  29   a  and the second positive airflow port  29   b,  a single valve may be utilized. 
     Referring still to  FIGS.  1 - 3  and  5   , in this exemplary embodiment, the manifold  22  further includes a first valve  17  and a second valve  18  which regulate the positive airflow provided by the positive air pressure source  23  to the first positive air flow port  29   a  and the second positive air flow port  29   b,  respectively, and thus the positive air pressure lines  28   a,    28   b  in fluid communication therewith. In this regard, the first valve  17  and the second valve  18  are each configured to transition between an open configuration to permit the positive airflow from the positive air pressure source  23  to be directed through the first positive air flow port  29   a  and the second positive air flow port  29   b,  respectively. Accordingly, the first valve  17  and the second valve  18  are in fluid communication with both the vacuum source  25  and one of the positive air pressure lines  28   a,    28   b  corresponding to the positive air flow ports  29   a,    29   b.  In the closed configuration, the first valve  17  and the second valve  18  block any airflow from the positive air pressure source  23  to the first positive air pressure line  28   a  and the second positive air pressure line  28   b,  respectively. Conversely, airflow from the positive air pressure source  23  is permitted to pass into the first positive air pressure line  28   a  and the second positive air pressure line  28   b  when the first valve  17  and the second valve  18 , respectively, are in the open configuration. In this exemplary embodiment, the transition of the first valve  17  and the second valve  18  between the open configuration and the closed configuration is regulated by the controller  40 . To this end, and in this exemplary embodiment, the first valve  17  and the second valve  18  are solenoid valves that are operably connected to the controller  40 , such that the controller  40  can selectively communicate instructions (signals) to transition each of the first valve  17  and the second valve  18  between the open configuration and the closed configuration. 
     Referring still to  FIGS.  1 - 3  and  5   , in this exemplary embodiment, in addition to preventing debris buildup within vacuum sensor lines  24   a,    24   b,  the debris evacuation system  20  can also be utilized to direct airflow from the positive air pressure source  23  into the vacuum lines  33   a,    33   b,    33   c,    33   d  to promote the release of (or “blow off”) a parcel engaged with one or more vacuum cups  35   a,    35   b,    35   c,    35   d  of the end effector  34  and/or clear the vacuum lines  33   a,    33   b,    33   c,    33   d  of debris present therein. To this end, and in this exemplary embodiment, the manifold  22  also includes a third valve  19 , which is in fluid communication with the positive air pressure source  23 , the vacuum source  25 , and the vacuum ports  31   a,    31   b,    31   c,    31   d.  The third valve  19  is also configured to transition between a first configuration and a second configuration. In the first configuration, the third valve  19  permits a flow of air to be drawn through the vacuum cups  35   a,    35   b,    35   c,    35   d  and corresponding vacuum lines  33   a,    33   b,    33   c,    33   d  while the vacuum source  25  is activated to draw a vacuum, but blocks any flow or air generated by the positive air pressure source  23 . In the second configuration, the third valve  19  permits a positive flow of air to be expelled through the vacuum lines  33   a,    33   b,    33   c,    33   d  and corresponding vacuum cups  35   a,    35   b,    35   c,    35   d  when the positive air pressure source  23  is activated to emit a flow of air, but blocks any flow of air generated by the vacuum source  25 . In this exemplary embodiment, the transition of the third valve  19  between the first configuration and the second configuration is also regulated by the controller  40 . To this end, in this exemplary embodiment, the third valve  19  is a solenoid valve that is operably connected to the controller  40 , such that the controller  40  can selectively communicate instructions (signals) which cause the third valve to transition between the first configuration and the second configuration. The controller  40  can thus communicate instructions to the positive air pressure source  23 , the vacuum source  25 , and the third valve  19  to regulate whether a vacuum is drawn or a positive air pressure is provided through each of the vacuum lines  33   a,    33   b,    33   c,    33   d  and corresponding vacuum cups  35   a,    35   b,    35   c,    35   d  at a given time. Although represented in the drawings as a single valve, embodiments, are contemplated, in which multiple valves are used to regulate the drawing of a vacuum and application of a positive air pressure through the vacuum cups  35   a,    35   b,    35   c,    35   d  and corresponding vacuum lines  33   a,    33   b,    33   c,    33   d.  Furthermore, embodiments are contemplated in which the debris evacuation system  20  includes one or more valves for each respective vacuum cup  35   a,    35   b,    35   c,    35   d,  such that each vacuum cup  35   a,    35   b,    35   c,    35   d  can independently draw a vacuum or be provided with positive air pressure. 
     Referring now again to  FIGS.  1 - 5   , the distal end of each vacuum sensor line  24   a,    24   b,    24   c,    24   d  is placed in fluid communication with one of the vacuum sensor ports  36   a,    36   b,    36   c  of the end effector  34 , while the proximal end of each vacuum sensor line  24   a,    24   b,    24   c,    24   d  is placed in fluid communication with one of the vacuum sensor ports  27   a,    27   b,    27   c,    27   d  of the manifold  22 , either directly or indirectly. In this exemplary embodiment, the debris evacuation system  20  further includes one or more connectors  26   a,    26   b,  where each connector is configured to connect and place one of the positive air pressure lines  28   a,    28   b  in fluid communication with one of the vacuum sensor lines  24   a,    24   b.  The number of connectors  26   a,    26   b  corresponds to the number of positive air pressure lines  28   a,    28   b  in use. Accordingly, in this exemplary embodiment, there are two connectors: a first connector  26   a,  which is configured to connect and place the distal end of the first positive air pressure line  28   a  in fluid communication with a proximal end of a first vacuum sensor line  24   a;  and a second connector  26   b,  which is configured to connect and place the distal end of the second positive air pressure line  28   b  in fluid communication with a proximal end of a second vacuum sensor line  24   b.  The first connector  26   a  and the second connector  26   b  are also configured, respectively, to connect the vacuum sensor lines  24   a,    24   b  and the positive air pressure line  28   a,    28   b  to one of the vacuum sensor ports  27   a,    27   b  of the manifold  22 . In this exemplary embodiment, the first connector  26   a  and the second connector  26   b  are both tee connectors. In this exemplary embodiment, the first connector  26   a  thus includes: a first end that is configured to engage the proximal end of the first vacuum sensor line  24   a;  a second end that is configured to engage the distal end of the first positive air pressure line  28   a;  and a third end that is configured to engage the first vacuum sensor port  27   a,  which is in fluid communication with the first vacuum sensor  21   a.  The second connector  26   b  similarly includes: a first end that is configured to engage the proximal end of the second vacuum sensor line  24   b;  a second end that is configured to engage the distal end of the second positive air pressure line  28   b;  and a third end that is configured to engage the second vacuum sensor port  27   b,  which is in fluid communication with the second vacuum sensor  21   b.  In this exemplary embodiment, the first end and the second end of each connector  26   a,    26   b  defines a port in which the proximal end of the vacuum sensor line  24   a,    24   b  and the distal end of the positive air pressure line  28   a,    28   b  in which the connector  26   a,    26   b  is received, and the third end of each connector  26   a,    26   b  is a male member that is configured to be inserted into the vacuum sensor port  27   a,    27   b  to which the connector  26   a,    26   b  corresponds. It should be appreciated, however, that alternative connectors suitable for connecting the first vacuum sensor line  24   a  and the second vacuum sensor line  24   b  to the first positive air pressure line  28   a  and the second positive air pressure line  28   b  as well as the first vacuum sensor port  27   a  and the second vacuum sensor port  27   b  in the manner described above can alternatively be used without departing from the spirit or scope of the present invention. 
     Referring now specifically to  FIG.  3   , in instances where the diameter of the vacuum sensor lines  24   a,    24   b  and/or positive air pressure lines  28   a,    28   b  do not correspond with the diameter of the ports defined by the first end and the second end of the connectors  26   a,    26   b,  respectively, as to provide a substantially airtight connection, intermediate adapters  37   a,    37   b,    38   a,    38   b  may be utilized to connect the connectors  26   a,    26   b  to the corresponding vacuum sensor lines  24   a,    24   b  and positive air pressure lines  28   a,    28   b.  Similarly, in instances where the diameter of the vacuum sensor lines  24   c,    24   d  directly connected to the vacuum sensor ports  27   c,    27   d  and/or the diameter of the male member defined by the third end of the connectors  26   a,    26   b  does not correspond with the diameter of the vacuum sensor ports  27   a,    27   b,    27   c,    27   d  in which they are inserted, intermediate adapters  39   a,    39   b,    39   c,    39   d  can also be utilized. 
     Referring now to  FIGS.  1  and  4   , in this exemplary embodiment, the debris evacuation system  20  further includes a filter  50  that is configured to collect dust or other debris carried by air passed therethrough. In this exemplary embodiment, the filter  50  is provided on and is in fluid communication with the distal end of one of the vacuum sensor lines  24   a  that, in turn, is in fluid communication with one of the positive air pressure lines  28   a.  The filter  50  is thus also positioned upstream of the vacuum sensor  21   a  with which the vacuum sensor line  24   a  is in fluid communication. Alternative embodiments are, however, contemplated in which the filter  50  is provided on a vacuum sensor line which is directly connected to the manifold  22  (i.e., not in fluid communication with a positive air pressure line  28   a,    28   b ) as well as embodiments in which the filter  50  is alternatively positioned (e.g., near the proximal end of a vacuum sensor line). In this example, the debris evacuation system  20  is described as including only a single filter  50  in fluid communication with one of the vacuum sensor lines  24   a,  but, as should be clear from the description provided herein, in most embodiments, it is expected that each vacuum sensor  24   a,    24   b,    24   c,    24   d  would be associated and in fluid communication with a filter. Accordingly, embodiments in which the debris evacuation system  20  includes multiple filters are also contemplated herein. One suitable filter  50  for use in the present invention is a filter selected from the ZFC In-line Air Filter series manufactured by SMC Corporation and available, for instance, from OTP Industrial Solutions of Louisville, Ky. 
     Referring now to  FIGS.  1 ,  4 , and  5   , while the parcel handling system  10  is in use, the robotic framework  32  is moved as to place the one or more vacuum cups  35   a,    35   b,    35   c,    35   d  of the end effector  34  into engagement with a target parcel (not shown). Upon or prior to such engagement, the controller  40  communicates instructions which activate the vacuum source  25  to draw a vacuum. At such time, and if the third valve  19  is not already in the first configuration, the controller  40  will also communicate instructions which cause the third valve  19  to transition from the second configuration to the first configuration to permit air to be drawn through the vacuum cups  35   a,    35   b,    35   c,    35   d  and corresponding vacuum lines  33   a,    33   b,    33   c,    33   d,  so that the end effector  34  can apply a suction force sufficient to lift and hold the target parcel. Upon reaching the intended destination where the target parcel is to be delivered, the target parcel is released from the end effector  34 . In this regard, release of the target parcel may be effectuated by virtue of the controller  40  communicating instructions which deactivate the vacuum source  25  (i.e., cause the vacuum source  25  to stop drawing a negative flow of air through one or more of the vacuum cups  35   a,    35   b,    35   c,    35   d  with which the target parcel is engaged), thereby removing the suction force holding the target parcel in association with the end effector  34 . In some implementations, in addition (or even as an alternative) to the deactivation of the vacuum source  25 , the controller  40  may communicate instructions which activate the positive air pressure source and cause the third valve  19  to transition to the second configuration, resulting in a positive flow of air being directed through the vacuum lines  33   a,    33   b,    33   c,    33   d  and into the corresponding vacuum cups  35   a,    35   b,    35   c,    35   d.  The introduction of the positive flow of air resulting from the activation of the positive air pressure source  23  quickly returns the vacuum cups  35   a,    35   b,    35   c,    35   d  to normal atmospheric pressure, effectively “blowing” the target parcel off of the end effector  34 . 
     Referring now again to  FIGS.  1 - 5   , following, or simultaneously with, the release of the target parcel, the controller  40  communicates instructions which places the first valve  17  and the second valve  18  in the open configuration and activate the positive air pressure source  23  to direct a flow of air into the positive air pressure lines  28   a,    28   b,  which is subsequently directed through the connectors  26   a,    26   b,  and through the vacuum sensor lines  24   a,    24   b  in fluid communication therewith, thus promoting evacuation of dust or other debris from such vacuum sensor lines  24   a,    24   b  and the filter  50 . To better ensure the accuracy of each reading obtained by the vacuum sensors  21   b,    21   c  corresponding to the vacuum sensor lines  24   a,    24   b  in fluid communication with positive air pressure lines  28   a,    28   b,  it is generally preferred that the controller  40  selectively activate the positive air pressure source  23 , and that the first valve  17  and the second valve  18  be placed or remain in the open configuration, each time a parcel is delivered to its intended destination. Furthermore, to avoid potential downtime between the robot singulator  30  delivering one parcel and engaging another parcel it is generally preferred that the controller  40  selectively activate the positive air pressure source  23 , and, if needed, communicate instructions which cause the first valve  17  and the second valve  18  to transition from the closed position to the open position, simultaneously or substantially simultaneously with the release of a parcel, especially in instances where positive air pressure is directed to the vacuum cups  35   a,    35   b,    35   c,    35   d  to promote the release of (or “blow off”) a parcel from the end effector  34 . The expulsion of air through the vacuum sensor lines  24   a,    24   b,  when occurring at the same time as positive air pressure is directed through the vacuum lines  33   a,    33   b,    33   c,    33   d  and corresponding vacuum cups  35   a,    35   b,    35   c,    35   d  to release the parcel, prevents the positive air pressure directed through the vacuum cups  35   a,    35   b,    35   c,    35   d  from pushing debris back into the vacuum sensor lines  24   a,    24   b.  Once, the vacuum sensor lines  24   a,    24   b  have been cleared of debris by virtue of the positive air pressure generated by the positive air pressure source  23  passing therethrough, the above-described process can be repeated to engage and transfer additional parcels while guarding against debris build up. 
     It should be appreciated that the controller  40  can be alternatively programmed (via instructions stored in the memory component  44 ) to evacuate debris from the vacuum sensor lines  24   a,    24   b  in fluid communication with the positive air pressure source  23  at times and/or upon the occurrence of events which differ from that of the preferred implementation described above. For instance, in some implementations, the controller  40  may be configured to communicate instructions which cause the debris evacuation system  20  to evacuate debris from the vacuum sensor lines  24   a,    24   b  in fluid communication with the positive air pressure source  23  at predetermined time intervals while the parcel handling system  10  is in use. In such implementations, if a predetermined time for evacuation coincides with a time in which the end effector  34  is engaged with and is transferring a parcel, the evacuation of the vacuum sensor lines  24   a,    24   b  in fluid communication with the positive air pressure source  23  may be delayed until the parcel has been released from the end effector  34 . In other implementations, the controller  40  may be configured to communicate instructions which cause the debris evacuation system  20  to evacuate the debris from such vacuum sensor lines  24   a,    24   b  soon after the parcel handling system  10  is initialized for use. 
     Although the debris evacuation system  20  is described herein as including only two positive air pressure lines  28   a,    28   b,  as noted above, in most embodiments, each vacuum sensor line  24   a,    24   b,    24   c,    24   d,  will be placed in fluid communication with a corresponding connector and positive air pressure line so that the vacuum sensor line  24   a,    24   b,    24   c,    24   d  corresponding to each vacuum cup  35   a,    35   b,    35   c,    35   d  of the end effector  34  can be evacuated of dust and other debris in the manner described above. Furthermore, although the debris evacuation system  20  is primarily in the context of being utilized in combination with a parcel handling system, it should be appreciated that the debris evacuation system  20  can be implemented in other systems employing the use of a vacuum-based end effector. 
     It is appreciated that each operation performed by the parcel handling system  10 , and, in particular, the debris evacuation system  20  thereof, can also be characterized as a method step, unless otherwise specified. Accordingly, the present invention is also directed to a method for preventing debris buildup in vacuum sensor lines, in which some or all of the various operations described above and performed by the parcel handling system  10  correspond to a step within the method. 
     One of ordinary skill in the art will recognize that additional embodiments and implementations are also possible without departing from the teachings of the present invention. This detailed description, and particularly the specific details of the exemplary embodiments and implementations disclosed herein, are given primarily for clarity of understanding, and no unnecessary limitations are to be understood therefrom, for modifications will become obvious to those skilled in the art upon reading this disclosure and may be made without departing from the spirit or scope of the invention.