SYSTEMS AND METHODS FOR HOSE GUIDANCE IN PROGRAMMABLE MOTION SYSTEMS

Description

BACKGROUND

[0001] The invention generally relates to programmable motion systems, and relates in particular to robotic systems, such as robotic pick-and-place systems whose task is to move objects from one location to another. The application for such systems could include any kind of material handling system that might benefit from automation, including automated package handling, automated order fulfillment, or automated store stock replenishment.

[0002] Some such robotic pick-and-place systems may employ vacuum gripping to pick items. Many common vacuum systems generate a vacuum at the end effector using a Venturi pump, which involves providing high pressure (e.g., 550 kPa (80 psi)) air blown over an aperture to generate a vacuum at the aperture, and which vacuum is used for picking up objects, such as products, packages, boxes, shipping bags, etc. These systems require a low enough quantity of air that a small diameter (e.g., less than 6 mm (1 / 4")) hose can be used to supply the high-pressure air at the end-effector. Such small diameter hoses are flexible enough, e.g., have a small enough bending radius, that they may be easily routed to the end-effector in a way that accommodates the motion of the robot e.g., an articulated arm in a large workspace. In such systems, the routing of the hose, for example, typically follows the contours of the articulated arm, bending or rotating with each joint of the articulated arm.

[0003] On the other hand, some robotic pick-and-place systems have been designed to grip items where leaks cannot be prevented. In order to sustain a vacuum, the system needs to compensate for the air loss from leaks. Such systems therefore must be able to pull a large amount of air through the vacuum gripper compared with the aforementioned Venturi pump-generated vacuum approach. These higher flow vacuum sources cannot typically be generated at the end-effector, and instead are often generated by a stationary blower placed near the robot. In such systems, however, instead of having a small amount of high-pressure air being pushed to the end-effector through a small diameter hose, significantly more air is pulled from the end-effector by a lower pressure vacuum through a much larger diameter hose. Because friction in the hose increases with the square of the air speed, the higher air flow necessitates a larger diameter hose. Doubling the hose diameter halves the required air speed for the same volumetric air flow, thus larger diameter hoses reduce friction and losses.

[0004] Larger diameter hoses, however, are problematic. Larger diameter hoses are less flexible, they take up more space, and they are heavier, all of which makes it difficult to provide the robot with the freedom of movement within a large workspace. Larger hoses need to be rigid enough to withstand collapse under vacuum, yet pliable enough to provide enough flexibility to accommodate the movement of the robot arm in its workspace. Many such hoses are made of plastic and attain their limited flexibility by being designed in a helical lip configuration, where, for example, a continuous helical lip is provided along the length of the hose. Figure 1, for example, shows two such hoses at 10 and 12. The hose 10 includes a helical lip 14, and may have an inner diameter d 1 of about 20 mm to about 40 mm. The hose 12 includes a helical lip 16, and may have an inner diameter d 2 of about 40 mm to about 80 mm.

[0005] Where a bend forms in the hose, the bend in the lip has some freedom of movement that gives the overall hose some bending compliance. The bend in the continuous lip, however, may fail under cyclic loading, e.g., if the hose is repeatedly bent beyond its intended bending radius, or if it is repeatedly bent and unbent over a relatively long period of time. A robotic pick-and-place system, for example, may undergo millions of back-and-forth movements per year, and a poorly designed air handling design that subjects a hose to millions of bends per year will cause the hose to fail.

[0006] Figures 2A - 2D show a pair of adjacent arm sections 20, 22 of an articulated arm programmable motion system, where each arm section 20, 22 is connected to a joint 24 having an axis of rotation A about which the arm sections 20, 22 may be rotated with respect to each other as shown. In particular, Figures 2B, 2C and 2D show the arm sections 20, 22 rotated progressively further about joint 24. A section of the hose that is near the j oint, referred to herein as a joint section of the hose 26, moves with the arms sections, but may become bound up against itself as shown at 28 in Figure 2D when the arm sections are rotated very close to one another. With reference to Figures 3A and 3B, a hose section 36 mounted on the outside of a joint 34 as arm sections 30, 32 rotate, may even bind against the joint itself as shown in Figure 3B. As the robot's arm bends at the joint, the hose bends in the same plane, the axis of rotation A (shown in Figures 2A - 2D) being normal to the plane. In other words, as the robot's arm rotates about the axis A during a motion, the hose bends with it, causing significant changes in the bending of the hose. Further, as the joined sections rotate from an angle (e.g., 90 degrees) to vertical (e.g., 180), and then further to an opposite angle, the hose must accommodate the changes in angular positions. As mentioned above, such an operation may be repeated many millions of times, which will cause significant strain on common plastic hoses. Certain further types of hose routing systems involve having a mechanism for gathering or releasing a hose (e.g., slack) as the articulated arm extends or rotates.

[0007] The requirements for mobility and freedom of movement within the workspace are particularly challenging. In addition to needing the hose to bend, a robot that swings up to 360 degrees about its base will need the hose to twist. The end-effector often needs to attain a large number of possible orientations in certain applications, which means that the attachment from the end-effector to the hose needs to accommodate the multitude of directions in which the hose mount needs to point as the robot moves from one place to another, for example, picking up items in arbitrary orientations.

[0008] While cable routing schemes exist for numerous types of cables and are suitable for narrow hoses, none satisfies the needs of using a large diameter hosing system on a small scale robot. There remains a need therefore, for a hose routing scheme for large diameter hoses in programmable motion devices. US 4 767 257 A discloses an industrial robot.SUMMARY

[0009] In accordance with an aspect, the invention provides a programmable motion robotic system in as recited in the appended independent claim 1.

[0010] In accordance with another aspect, the invention provides a method of providing a high flow vacuum source to an end effector of a programmable motion robotic system as recited in the appended independent claim 10.

[0011] Some further optional features are recited in the appended dependent claims.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The following may be further understood with reference to the accompanying drawings in which: Figure 1 shows an illustrative diagrammatic view of two large diameter vacuum hoses; Figures 2A - 2D show illustrative diagrammatic views of two arm sections of an articulated arm with a section of a hose attached to the arm sections of the prior art with the hose section inside of a bend joint; Figures 3A and 3B show illustrative diagrammatic views of two arm sections of an articulated arm with a section of a hose attached to the arm sections of the prior art with the hose section outside of a bend joint; Figures 4A and 4B show illustrative diagrammatic views of two arm sections of an articulated arm with a section of a hose attached the arm sections in accordance with an aspect of the invention showing two different views of the arm sections in the same position; Figures 5A and 5B show illustrative diagrammatic views of two arm sections of an articulated arm with a section of a hose attached the arm sections in accordance with an aspect of the invention showing the hose section bent toward the viewing direction; Figures 6A and 6B show illustrative diagrammatic views of two arm sections of an articulated arm with a section of a hose attached the arm sections in accordance with an aspect of the invention showing the hose section bent away from the viewing direction; Figure 7 shows an illustrative graphical representation of joint angle verses potential energy due to bending for in-plane and out-of-plane hose bending; Figure 8 shows an illustrative diagrammatic view of an articulated arm system showing an axis of rotation of a joint B and a plane C in which a hose section is positioned; Figure 9 shows an illustrative diagrammatic view of the articulated arm system of Figure 8 showing the axis of rotation of the same joint shown in Figure 8 showing planes running perpendicular to the joint; Figure 10 shows an illustrative diagrammatic rear view of the articulated arm system of Figure 8; Figure 11 shows an illustrative diagrammatic rear view of the articulated arm system of Figure 10 with a plurality of arm sections having been rotated about a plurality of joints; Figure 12 shows an illustrative diagrammatic right side view of the articulated arm system of Figure 10; Figure 13 shows an illustrative diagrammatic right side view of the articulated arm system of Figure 11; Figure 14 shows an illustrative diagrammatic top view of the articulated arm system of Figure 10; Figure 15 shows an illustrative diagrammatic top view of the articulated arm system of Figure 11; Figure 16 shows an illustrative diagrammatic front view of the articulated arm system of Figure 10; Figure 17 shows an illustrative diagrammatic front view of the articulated arm system of Figure 11; Figure 18 shows an illustrative diagrammatic left side view of the articulated arm system of Figure 10; Figure 19 shows an illustrative diagrammatic left side view of the articulated arm system of Figure 11; Figure 20 shows an illustrative diagrammatic rear view of the articulated arm system of Figure 8 showing a hose section plane E that is parallel with an axis of rotation D of an associated joint; Figure 21 shows an illustrative diagrammatic view of two arm sections showing a hose section plane F that is parallel with an axis of rotation G of an associated joint; Figure 22 shows an illustrative diagrammatic enlarged side view of the articulated arm system of Figure 20; Figures 23A - 23D show illustrative diagrammatic views of an articulated arm system in a working environment moving objects while employing a hose routing system in accordance with an aspect of the present invention; Figure 24 shows an illustrative diagrammatic rear view of the articulated arm system of Figure 8 employing fixed position hose mounts in accordance with an aspect of the invention; Figure 25 shows an illustrative diagrammatic rear view of the articulated arm system of Figure 8 employing swivel hose mounts not according to the invention; Figure 26 shows an illustrative diagrammatic view of an articulated arm system in accordance a further aspect of the invention employing a routing scheme that includes a hose section that spans a plurality of arm sections and joints, showing a hose section plane I that is parallel with an axis of rotation H of a joint of the plurality of joints; and Figure 27 shows an illustrative diagrammatic view of an articulated arm system of Figure 26 employing the routing scheme that includes the hose section that spans the plurality of arm sections and joints, showing planes running perpendicular to the j oint of the plurality of joints.

[0013] The drawings are shown for illustrative purposes only.DETAILED DESCRIPTION

[0014] In accordance with various embodiments, the invention provides a method of mounting a large diameter cabling or hose on a multi-link mechanical system that (1) minimizes changes to the bending of a hose during motion, and (2) minimizes the maximum bending of such a hose in potential robot configurations.

[0015] Instead of bending in the plane of the motion of the rotating links (articulated arm sections), the hose is mounted in a way that it bends out of the plane of the articulated arm sections' motion. As shown in Figures 4A and 4B from two views, a hose section 46 is attached to two arm sections 40, 42 at two ends rigidly with a fixed mount. The arm sections 40, 42 are each coupled to a joint 44. Being mounted rigidly, the tangents to the hose at these points are nearly perpendicular to the plane of motion, or set at an angle that reduces both the maximum bending, and maximum change in bending.

[0016] As the attachment points are positioned closed to each other, the hose tangents at the attachment points become nearer to perpendicular to the plane of motion.

[0017] Figures 5A and 5B show arm sections 50, 52 of an articulated arm programmable motion robotic system that are coupled to a joint 54, with a joint portion of a hose 56 attached to the arm sections. The joint potion of the hose 56 remains out of plane with respect to the joint 54.

[0018] Figures 6A and 6B show similar arm sections 60, 62 that are coupled to a joint 64 with a joint hose portion 66 on a far side (with respect to Figures 5A and 5B) of the joint 64. As shown in Figures 5A - 6B, the joint hose section is not required to be on any particular side of the joint.

[0019] Though there remains a change in the bending during a motion, the degree of change in bending is lower than in a common hose routing scheme, as shown before. The strain - or change in bending - over the course of the motions is lower than with the in-plane scheme.

[0020] Figure 7 shows a graphical representation of the total bending energy of the two schemes vs. the angle of rotation between arm sections. The in-plane scheme has higher hose stress and change in hose stress over the different motions. In particular, Figure 7 shows at 70 the amount of potential energy (in Joules) due to bending over joint angles in a conventional in-plane routing technique in which a hose is mounted to arm sections such that it rotates in the plane of the joint. Figure 7 shows at 72 the amount of potential energy (in Joules) due to bending over joint angles in a system incorporating routing in accordance with aspects of the present invention. Note that the range of potential energy values for the out-of-plane routing, r 1 , is substantially less than the range of potential energy values for the in-plane routing, r 2 . Although the hose will still experience some stress, the range of change in such stress (as well as the highest amount of such stress) will be significantly less.

[0021] Figure 8 shows at 80 an articulated arm programmable motion robotic system that includes a vacuum end effector 82 (e.g., including a flexible bellows) that is coupled to a vacuum source 84 by a hose 86. The system includes a base 88 that supports an articulated arm 90 having arm sections 92, 94, 96 and 98. A section of the hose, hose section 100, is coupled to adjacent arm sections 92, 94 that are each coupled to a joint 102 by which the arm sections 92, 94 may be rotated about an axis B. The joint portion of the hose 100 is mounted to define a plane 104 (e.g., through the center of the hose section 100), and such plane 104 is defined by having a plurality of directions as shown at 106. In accordance with an aspect of the invention, one of these directions (C as labelled) is parallel with the axis B.

[0022] Figure 9 shows the system 80 that includes the articulated arm programmable motion robotic system that includes the vacuum end effector 82 that is coupled to the vacuum source 84 by the hose 86. Again, the system includes the base 88 that supports the articulated arm 90 having arm sections 92, 94, 96 and 98. Similarly, the section of the hose 100 is coupled to adjacent arm sections 92, 94 that are each coupled to the joint 102 by which the arm sections 92, 94 may be rotated about an axis B as discussed with respect to Figure 8. During such rotation of the arm sections 92, 94 at the joint 102, the arm sections 92, 94 will define a plurality of planes as shown at 110. The plurality of planes 110 span the width of the joint 102. The joint portion of the hose 100 is mounted such that the joint portion of the hose 100 lies substantially outside of the plurality of planes 110.

[0023] In accordance with various aspects of the invention, the vacuum at the end effector may have a flow rate of at least 169.9 cubic meters per hour (100 cubic feet per minute), and a vacuum pressure of no more than 50,000 Pascals below atmospheric. The hose may have an inner diameter of at least 2.54 centimeters (1 inch) (or at least 7.62 centimeters (3 inches)), and may include a helical ribbing as discussed above.

[0024] To better show the system from multiple angles, Figure 10 shows a back perspective view of the system 80, Figure 12 shows a left side view of the system 80, Figure 14 shows a top view of the system 80, Figure 16 shows a front view of the system 80 and Figure 18 shows a left side perspective view of the system 80. Figures 11, 13, 15, 17 and 19 shows a system 80' in which the articulated arm of the system of Figures 10, 12, 14, 16 and 18 is moved such that the arm sections are extended in a single direction (to further show the hose routing). The components of the system of Figures 11, 13, 15, 17 and 19 are the same as those of Figures 10, 12, 14, 16 and 18. In particular, Figure 11 shows a back perspective view of the system 80', Figure 13 shows a right side view of the system 80', Figure 15 shows a top view of the system 80', Figure 17 shows a front view of the system 80' and Figure 19 shows a left side perspective view of the system 80'.

[0025] The hose routing of embodiments of the invention may be applied to a plurality of arm sections of an articulated arm system. Figure 20, for example, shows a system 80" that includes a base 88 that supports an articulated arm 90 having arm sections 92, 94, 96 and 98. A section of the hose, hose section 100', is coupled to adjacent arm sections 94, 96 that are each coupled to a joint 112 by which the arm sections 94, 96 may be rotated about an axis D. The joint portion of the hose 100' is mounted to define a plane 114 (e.g., through the center of the hose section 100'), and such plane 114 is defined by having a plurality of directions as shown at 116. In accordance with an aspect, one of these directions (E as labelled) is parallel with the axis D. In such a system, both the hose section 100 and the hose section 100' of the hose 86 may be routed in accordance with various aspects of the present invention. Figure 22 shows a close-up view of a portion of the system 80" of Figure 20. As may be seen in Figure 22, the hose section 100' defines a plane 114, for example, through a longitudinal center of the curved hose section 110'.

[0026] Figure 21 shows an example of such out-of-plane routing with a joint and arm sections as shown in Figures 4A - 6B. Such a system includes arm sections 120, 122 of an articulated arm programmable motion robotic system that are coupled to a joint 124, with a joint portion of a hose 126 attached to the arm sections. The joint potion of the hose 126 remains out of plane with respect to the joint 124. Again the plane F shown at 128 includes a direction that is parallel with an axis of rotation G of the joint 124.

[0027] Figures 23A - 23D show the articulated arm programmable motion robotic system 80 that includes the vacuum end effector 82 that is coupled to the vacuum source 84 by the hose 86. The system includes the base 88 that supports the articulated arm 90 having arm sections 92, 94, 96 and 98. The section of the hose 100 is coupled to adjacent arm sections 92, 94 that are each coupled to the joint 102 by which the arm sections 92, 94 may be rotated. The joint portion of the hose 100 is mounted to define a plane that includes a direction that is parallel with the axis of rotation of the joint as discussed above. Further, the joint portion of the hose 100 lies substantially outside of the plurality of planes 110 defined by movement of the arm sections 92, 94 as also discussed above. Similarly, section of the hose 100' is coupled to adjacent arm sections 94, 96 that are each coupled to a joint by which the arm sections 94, 96 may be rotated about an axis meeting the above requirements.

[0028] With reference to Figures 23A - 23D, the articulated arm system may be employed, under control of one or more computer processing system(s) 130 to move from one object 132 (Figure 23A) to another 134 (Figures 23B and 23C), and to then lift the new object 134. Note that when the arm sections 94 and 96 are moved to be very close to each other (shown in Figure 23C), the hose section 100' remains relatively free of bending and therefore stress.

[0029] The hose attachments may be fixed, may provide swiveling, and / or may provide for translation of the hose through the attachments in various aspects of the invention. The swivel attachments may also have more than one degree of freedom (DOF). While, the swivel may only allow rotation of the hose about an axis that is in the plane of the motion, a swivel joint may accommodate other additional DOFs including: the hose may twist through the mount to reduce torsion on the hose, the hose may slip through the mount to lengthen or shorten the hose segment between attachment points, and the attachment may permit small deflections of the rotation axis also to reduce total bending energy.

[0030] Figures 24 and 25 show articulated arm programmable motion robotic systems 140 and 140' that include the vacuum end effector 82 that is coupled to the vacuum source 84 by the hose 86. The systems include the base 88 that supports the articulated arm 90 having arm sections 92, 94, 96 and 98. The section of the hose 100 is coupled to adjacent arm sections 92, 94 that are each coupled to the joint 102 by which the arm sections 92, 94 may be rotated. Again, the joint portion of the hose 100 is mounted to define a plane that includes a direction that is parallel with the axis of rotation of the j oint as discussed above. Further, the j oint portion of the hose 100 lies substantially outside of the plurality of planes defined by movement of the arm sections 92, 94 as also discussed above. Similarly, section of the hose 100' is coupled to adjacent arm sections 94, 96 that are each coupled to a joint by which the arm sections 94, 96 may be rotated about an axis meeting the above requirements.

[0031] The hose attachments 142 of the system 140 are fixed position, yet (in an embodiment outside the literal scope of the claims) may optionally permit translation of the hose through the attachments as shown by the double ended arrows. The hose attachments 144 of the system 140' are swivel attachments that may rotate with the hose, and further may permit translation of the hose through the attachments as also shown by the double ended arrows. Note that the hose 86 in Figure 25 with the swivel attachments, appears to be more free of stress than the hose in Figure 24, and permits the hose to assume a wider variety of positions. In accordance with various aspects, the hose may be coupled to each attachment with a coupling that permits each hose section to rotate about the hose's central axis.

[0032] The system may also provide hose routing in accordance with aspects of the invention including hose attachments on non-adjacent arm sections. Figure 26, for example, shows at 180 an articulated arm programmable motion robotic system that includes a vacuum end effector 182 that is coupled to a vacuum source 184 by a hose 186. The system includes a base 188 that supports an articulated arm 190 having arm sections 192, 194, 196 and 198. A section of the hose, hose section 200, is coupled to non-adjacent arm sections 192, 196 that share a joint 202 therebetween. The joint 202 may be rotated about an axis H. The joint portion of the hose 200 is mounted to define a plane 204 (e.g., through the center of the hose section 200), and such plane 204 is defined by having a plurality of directions as shown at 206. In accordance with an aspect, one of these directions (I as labelled) is parallel with the axis H.

[0033] Figure 27 shows the system 180 that includes the articulated arm programmable motion robotic system that includes the vacuum end effector 182 that is coupled to the vacuum source 184 by the hose 186. Again, the system includes the base 188 that supports the articulated arm 190 having arm sections 192, 194, 196 and 198. Similarly, the section of the hose 200 is coupled to non-adjacent arm sections 192, 196 that share the joint 202 therebetween. The joint 202 may be rotated about the axis H as discussed with respect to Figure 26. During such rotation of the arm sections 194, 196 about the joint 202, the arm sections 192, 194 will define a plurality of planes as shown at 210. The plurality of planes 210 span the width of the joint 202. The joint portion of the hose 200 is mounted such that the joint portion of the hose 200 lies substantially outside of the plurality of planes 210.

[0034] The hose may not include any portions attached to at least two adjacent arm sections which are mutually attached to a respective joint, such that the joint portions of the hose may define a plane that includes a respective direction that is generally not parallel with an axis of rotation of the respective joint.

[0035] Hose routing approaches of various embodiments of the invention allow for a chain of such kinds of attachments and hose segments to be provided that would exploit out-of-plane motions for a multi-link articulated arm programmable motion robotic system, with the objective of minimizing the maximum bending energy, and reducing the amount of cyclic loading to which the hose would be subjected.

[0036] Those skilled in the art will appreciate that modifications and variations may be made the above disclosed embodiments without departing from the scope of the present invention as defined in the appended claims.

Claims

1. A programmable motion robotic system (80) comprising: a plurality of arm sections (92, 94, 96, 98) that are joined one to another at a plurality of joints (102) to form an articulated arm (90); and a hose (86) configured to couple an end effector (82) of the programmable motion robotic system to a vacuum source (84); wherein said hose includes at least three joint portions (100), each joint portion of the hose being rigidly attached to at least two adjacent arm sections (92, 94, 96, 98) of the plurality of arm sections mutually attached to a joint (102) of the plurality of joints such that each joint portion (100) of the hose (86) remains substantially outside of any plane of motion defined by motion of the mutually adjacent arm sections (92, 94, 96, 98) when rotated about the joint, wherein the tangents to the hose at each attachment point are nearly perpendicular to the plane of motion of the mutually adjacent arm sections.

2. The programmable motion robotic system (80) as claimed in claim 1, wherein the programmable motion robotic system further comprises a vacuum source coupled to the hose and providing, via the hose (86), a vacuum at the end effector (82) having a flow rate of at least 169.9 cubic meters per hour.

3. The programmable motion robotic system (80) as claimed in claim 1, wherein the programmable motion robotic system further comprises a vacuum source coupled to the hose and providing, via the hose (86), a vacuum at the end effector (82) having a vacuum pressure of no more than 50,000 Pascals below atmospheric.

4. The programmable motion robotic system (80) as claimed in claim 1, wherein the hose (86) has an inner diameter of at least 2.54 centimeters.

5. The programmable motion robotic system (80) as claimed in claim 1, wherein the hose (86) has an inner diameter of at least 7.62 centimeters.

6. The programmable motion robotic system (80) as claimed in claim 1, wherein the hose (86) has a helical ribbing.

7. The programmable motion robotic system (80) as claimed in claim 1, wherein the hose (86) includes no portions of the hose that is attached to at least two adjacent arm sections (92, 94, 96, 98) mutually attached to a respective joint (102) such that the joint portions (100) of the hose each remain substantially inside of any plane defined by motion of the mutually adjacent arm sections when rotated about the respective joint.

8. The programmable motion robotic system (80) as claimed in claim 1, wherein the end effector (82) includes a flexible bellows.

9. The programmable motion robotic system (80) as claimed in claim 1, wherein each joint portion of the hose defines a plane that includes a direction that is generally parallel with an axis of rotation of the joint.

10. A method of providing a high flow vacuum source to an end effector of a programmable motion robotic system (80), said method comprising: providing a hose (86) that couples the end effector (82) to a vacuum source (84), the hose including at least three joint portions (100), each joint portion being proximate a respective joint (102) of the programmable motion robotic system; and rotating at least one arm section (92, 94, 96, 98) attached to a joint (102) about an axis of rotation of the joint; wherein each joint portion (100) of the hose (86) is rigidly attached to at least two adjacent arm sections (92, 94, 96, 98) mutually attached to a respective joint (102) such that each joint portion of the hose remains substantially outside of any plane of motion defined by motion of the mutually adjacent arm sections when rotated about the joint, wherein the tangents to the hose at each attachment point are nearly perpendicular to the plane of motion of the mutually adjacent arm sections, and wherein the joint portions of the hose define a plane that includes a respective direction that is generally parallel with the axis of rotation of the joint.

11. The method as claimed in claim 10, wherein the vacuum source provides, via the hose (86), a vacuum at the end effector (82) having a flow rate of at least 169.9 cubic meters per hour .

12. The method as claimed in claim 10, wherein the vacuum source provides, via the hose (86), a vacuum at the end effector (82) having a vacuum pressure of no more than 50,000 Pascals below atmospheric.

13. The method as claimed in claim 10, wherein the hose (86) has a helical ribbing.

14. The method as claimed in claim 10, wherein the hose (86) includes no portions of the hose that is attached to at least two adjacent arm sections (92, 94, 96, 98) mutually attached to a respective joint such that the joint portions (100) of the hose defines a plane that includes a respective direction that is generally not parallel with an axis of rotation of the respective joint.

15. The method as claimed in claim 10, wherein the end effector (82) includes a flexible bellows.