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US-20260124768-A1 - ROBOTIC DEVICES AND METHODS FOR FABRICATION, USE AND CONTROL OF SAME

US20260124768A1US 20260124768 A1US20260124768 A1US 20260124768A1US-20260124768-A1

Abstract

Various embodiments relate to magnetically moveable displacement devices or robotic devices. Particular embodiments provide systems and corresponding methods for magnetically moving multiple movable robots relative to one or more working surfaces of respective one or more work bodies, and for moving robots between the one or more work bodies via transfer devices. Robots can carry one or more objects among different locations, manipulate carried objects, and/or interact with their surroundings for particular functionality including but not limited to assembly, packaging, inspection, 3D printing, test, laboratory automation, etc. A mechanical link may be mounted on planar motion units such as said robots.

Inventors

  • Xiaodong Lu
  • Peter Tang
  • Alexander H. Slocum
  • Rui Chen

Assignees

  • PLANAR MOTOR INCORPORATED

Dates

Publication Date
20260507
Application Date
20251219

Claims (20)

  1. 1 . An apparatus for moving one or more magnetically moveable devices, the apparatus comprising: a work body comprising a plurality of electrically conductive coils and a work surface upon which the one or more magnetically moveable devices are configured to be moved; and one or more controllers configured to move the one or more magnetically moveable devices over the work surface by driving one or more currents through at least one of the plurality of electrically conductive coils so as to modulate one or more magnetic fields and thereby controllably and magnetically levitate the one or more magnetically moveable devices, wherein, for at least one of the one or more magnetically moveable devices that is levitating, the one or more controllers are further configured to: determine that the at least one magnetically moveable device is idling; and in response to determining that the at least one magnetically moveable device is idling, land the at least one magnetically moveable device on the work surface and thereby decrease average power consumption.
  2. 2 . The apparatus of claim 1 , wherein the one or more controllers are further configured to: determine that the one or more controllers are not currently causing the at least one magnetically moveable device to be moved; and in response to determining that the one or more controllers are not currently causing the at least one magnetically moveable device to be moved, determine that the at least one magnetically moveable device is idling.
  3. 3 . The apparatus of claim 1 , wherein the one or more controllers are further configured to: determine that a trajectory assigned to the at least one magnetically moveable device has not changed for a certain amount of time; and in response to determining that the trajectory assigned to the at least one magnetically moveable device has not changed for the certain amount of time, determine that the at least one magnetically moveable device is idling.
  4. 4 . The apparatus of claim 1 , wherein the one or more magnetically moveable devices are configured to be moved over the work surface in at least three degrees of freedom, including a degree of freedom along an x-axis parallel to the work surface, a degree of freedom along a y-axis parallel to the work surface, and a degree of freedom along a z-axis normal to the work surface and normal to the x-axis and the y-axis.
  5. 5 . The apparatus of claim 4 , wherein the at least three degrees of freedom consist of six degrees of freedom, including a rotational degree of freedom about the x-axis, a rotational degree of freedom about the y-axis, and a rotational degree of freedom about the z-axis.
  6. 6 . The apparatus of claim 1 , wherein the one or more controllers are further configured to: in response to determining that the at least one magnetically moveable device is idling, land the at least one magnetically movable device according to a soft-landing sequence by progressively reducing the one or more currents through the at least one electrically conductive coil to progressively lower the at least one magnetically moveable device to the work surface.
  7. 7 . The apparatus of claim 6 , wherein the one or more controllers are further configured to: during the lowering of the at least one magnetically moveable device: monitor a force applied along a degree of freedom to the at least one magnetically moveable device; and in response to determining that the monitored force is exceeding a threshold, switch from a closed-loop control mode to an open-loop control mode and set a force command generated by the one or more controllers for applying a force to the at least one magnetically moveable device along the degree of freedom is set to a fixed value.
  8. 8 . The apparatus of claim 1 , wherein the one or more controllers are further configured to: after landing the at least one magnetically movable device on the work surface and in response to determining that the at least one magnetically moveable device is to be moved according to a trajectory assigned to the at least one magnetically moveable device, levitate the at least one magnetically movable device according to a soft-take-off sequence by progressively increasing the one or more currents through the at least one electrically conductive coil to progressively raise the at least one magnetically moveable device.
  9. 9 . The apparatus of claim 8 , wherein the one or more controllers are further configured to: during the raising of the at least one magnetically moveable device, control movement of the at least one magnetically moveable device according to each of six degrees of freedom, including a degree of freedom along an x-axis parallel to the work surface, a degree of freedom along a y-axis parallel to the work surface, a degree of freedom along a z-axis normal to the work surface and normal to the x-axis and the y-axis, a rotational degree of freedom about the x-axis, a rotational degree of freedom about the y-axis, and a rotational degree of freedom about the z-axis.
  10. 10 . The apparatus of claim 1 , wherein the one or more controllers are further configured to, in response to the at least one magnetically moveable device being landed on the work surface: monitor one or both of a position and an orientation of the of the at least one magnetically moveable device on the work surface; and generate one or more forces to maintain one or both of the position and the orientation of the at least one magnetically moveable device on the work surface.
  11. 11 . The apparatus of claim 1 , wherein the one or more controllers are further configured to: in response to the at least one magnetically moveable device being landed on the work surface, generate one or more forces to constrain movement of the at least one magnetically moveable device in at least one of three in-plane degrees of freedom.
  12. 12 . The apparatus of claim 11 , wherein the one or more controllers are further configured to: in response to the at least one magnetically moveable device being landed on the work surface, generate one or more forces to constrain movement of the at least one magnetically moveable device in each of the three in-plane degrees of freedom, consisting of a rotational degree of freedom and two translational degrees of freedom parallel to the working surface and perpendicular to one another.
  13. 13 . The apparatus of claim 1 , wherein the one or more controllers are further configured to: determine that no other magnetically moveable devices are within a preset distance of the landed at least one magnetically moveable device; and in response to determining that no other magnetically moveable devices are within a preset distance of the landed at least one magnetically moveable device, switching off one or more currents driving at least one of the plurality of electrically conductive coils and thereby further decrease average power consumption.
  14. 14 . The apparatus of claim 1 , wherein the one or more controllers are further configured to: determine that no disturbance force from another magnetically moveable device is affecting the at least one magnetically moveable device; and in response to determining that no disturbance force is affecting the at least one magnetically moveable device, switch off one or more currents driving at least one of the plurality of electrically conductive coils and thereby further decrease average power consumption.
  15. 15 . A method of controlling a magnetically moveable device, comprising: using magnetic induction to move the magnetically moveable device over a work surface, wherein the moving comprises: moving the magnetically moveable device, according to a programmed trajectory, from a first position over the work surface to a second position over the work surface; after moving the magnetically moveable device to the second position, determining that the magnetically moveable device is idling; and in response to determining that the magnetically moveable device is idling, landing the magnetically moveable device on the work surface and thereby decreasing average power consumption.
  16. 16 . The method of claim 15 , wherein determining that the magnetically moveable device is idling comprises: determining one or both of: (i) that the one or more controllers are not currently causing the magnetically moveable device to be moved; and (ii) that a trajectory assigned to the magnetically moveable device has not changed for a certain amount of time; and in response to determining one or both of (i) and (ii), determining that the magnetically moveable device is idling.
  17. 17 . The method of claim 15 , further comprising, in response to landing the magnetically moveable device on the work surface: monitoring one or both of a position and an orientation of the magnetically moveable device on the work surface; and generating one or more forces to maintain one or both of the position and the orientation of the magnetically moveable device on the work surface.
  18. 18 . The method of claim 15 , further comprising: in response to landing the magnetically moveable device on the work surface, generating one or more forces to constrain movement of the magnetically moveable device in at least one of three in-plane degrees of freedom.
  19. 19 . The method of claim 15 , further comprising: determining that no other magnetically moveable devices are within a preset distance of the landed magnetically moveable device; and in response to determining that no other magnetically moveable devices are within a preset distance of the landed magnetically moveable device, switching off one or more currents driving at least one of a plurality of electrically conductive coils and thereby further decreasing average power consumption.
  20. 20 . The method of claim 15 , further comprising: determining that no disturbance force from another magnetically moveable device is affecting the magnetically moveable device; and in response to determining that no disturbance force is affecting the magnetically moveable device, switching off one or more currents driving at least one of a plurality of electrically conductive coils and thereby further decreasing average power consumption.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application is a continuation of and claims priority to U.S. patent application Ser. No. 19/349,364 filed on Oct. 3, 2025, which is a continuation of and claims priority to U.S. patent application Ser. No. 19/179,720 filed on Apr. 15, 2025, which is a continuation of and claims priority to U.S. patent application Ser. No. 19/070,136 filed on Mar. 4, 2025, which was a continuation of and claims priority to U.S. Pat. No. 12,251,823 issued on Mar. 18, 2025, which was a continuation of and claims priority to U.S. Pat. No. 11,701,786 issued on Jul. 18, 2023, which was a continuation of and claims priority to U.S. Pat. No. 10,926,418 issued on Feb. 23, 2021 which was a 371 US National Phase Entry of PCT/CA2018/050375 filed on Mar. 27, 2018 and which claims priority to provisional patent application Nos. 62/476,871 filed Mar. 27, 2017, 62/485,402 filed Apr. 14, 2017, 62/490,270 filed Apr. 26, 2017, 62/513,975 filed Jun. 1, 2017, 62/590,323 filed Nov. 23, 2017, and 62/626,082 filed Feb. 4, 2018, the entire contents of which are incorporated by reference herein. TECHNICAL FIELD As discussed herein, various embodiments relate to magnetically moveable displacement devices or robotic devices. Particular embodiments provide systems and corresponding methods for magnetically moving multiple movable robots relative to one or more working surfaces of respective one or more work bodies, and for moving robots between the one or more work bodies via transfer devices. Robots can carry one or more objects among different locations, manipulate carried objects, and/or interact with their surroundings for particular functionality including but not limited to assembly, packaging, inspection, 3D printing, test, laboratory automation, etc. A mechanical link may be mounted on planar motion units such as said robots. The mechanical link may comprise revolute joints comprised of pairs of left and right helical gears preloaded against each other with magnets. The linkage system may be mounted on planar motion units where the linkage elements are comprised of plastic. BACKGROUND The following is meant to assist the reader by providing context to the description and is in no way meant as an admission of prior art. Motion stages (XY tables and rotary tables) are widely used in various manufacturing, inspection and assembling processes. A common solution currently in use achieves XY motion by stacking two linear stages (i.e. a X-stage and a Y-stage) together via connecting bearings. A more desirable solution may involve having a single moving stage capable of motion two or more different linear directions relative to the working surface, which may eliminate the need for additional bearings. It might also be desirable for such a moving stage to be able to move in a direction orthogonal to the working surface. Attempts have been made to design such displacement devices using the interaction between current flowing through electrically conductive elements and permanent magnets. Examples of efforts in this regard include the following: U.S. Pat. Nos. 6,003,230; 6,097,114; 6,208,045; 6,441,514; 6,847,134; 6,987,335; 7,436,135; 7,948,122; US patent publication No. 2008/0203828; W. J. Kim and D. L. Trumper, High-precision magnetic levitation stage for photolithography. Precision Eng. 22 2 (1998), pp. 66-77; D. L. Trumper, et al, “Magnet arrays for synchronous machines”, IEEE Industry Applications Society Annual Meeting, vol. 1, pp. 9-18, 1993; and J. W. Jansen, C. M. M. van Lierop, E. A. Lomonova, A. J. A. Vandenput, “Magnetically Levitated Planar Actuator with Moving Magnets”, IEEE Tran. Ind. App., Vol 44, No 4, 2008. More recent techniques for implementing displacement devices having a moveable stage are described in: PCT application No. PCT/CA2012/050751 (published under WO/2013/059934) entitled DISPLACEMENT DEVICES AND METHODS FOR FABRICATION, USE AND CONTROL OF SAME; andPCT application No. PCT/CA2014/050739 (published under WO/2015/017933) entitled DISPLACEMENT DEVICES AND METHODS AND APPARATUS FOR DETECTING AND ESTIMATING MOTION ASSOCIATED WITH SAME; andPCT application No. PCT/CA2015/050549 (published under WO/2015/188281) entitled DISPLACEMENT DEVICES, MOVEABLE STAGES FOR DISPLACEMENT DEVICES AND METHODS FOR FABRICATION, USE AND CONTROL OF SAME; andPCT application No. PCT/CA2015/050523 (published under WO/2015/184553) entitled METHODS AND SYSTEMS FOR CONTROLLABLY MOVING MULTIPLE MOVEABLE STAGES IN A DISPLACEMENT DEVICE; andPCT application No. PCT/CA2015/050157 (published under WO/2015/179962) entitled DISPLACEMENT DEVICES AND METHODS FOR FABRICATION, USE AND CONTROL OF SAME. Some other devices can achieve in-plane movement (e.g. in one or both the X and Y directions on an X-Y plane), but the motion ranges in other directions (e.g. the Z direction when the Z-axis is orthogonal to the X and Y axes, or rotational directions Rx, Ry, Rz about the X, Y, and Z axes) are limited. For example, moveable sta