Method of actuating a shape changeable member, shape changeable member and actuating system

Patent metadata

Field	Value
Publication number	US-11031160-B2
Application number	US-201716477593-A
Country	US
Kind code	B2
Filing date	Dec 22, 2017
Priority date	Jan 13, 2017
Publication date	Jun 8, 2021
Grant date	Jun 8, 2021

Abstract

The present invention relates to a method of actuating a shape changeable member of actuatable material. The invention further relates to a shape changeable member and to a system comprising such a shape changeable member and a magnetic field apparatus.

First claim

The invention claimed is:

1. A method of actuating a shape changeable member having a height, a width and a length, the shape changeable member further being untethered; the method comprising the steps of:
actuating the shape changeable member by means of at least one stimulus to bring about a change of shape of the shape changeable member at least over the length of the shape changeable member in at least one spatial direction and thereby inducing a torque into the shape changeable member;
effecting a locomotion of the shape changeable member by means of the induced change of shape of the shape changeable member in the at least one spatial direction; and
moving the shape changeable member in the at least one spatial direction,
wherein the stimulus is an external stimulus present in the form of a time varying magnetic field applied in at least one dimension and the shape changeable member is formed from a continuum of infinitesimal segments (ds), with the segments (ds) each comprising the same material but having a different direction of magnetization.

2. The method in accordance with claim 1 , wherein the induced torque is used to steer the shape changeable member in the at least one spatial direction.

3. The method in accordance with claim 1 , wherein a type of locomotion of the shape changeable member is selected from the group of members consisting of swimming, walking, flipping, crawling, rolling, diving, immersion, emersion, jumping, landing and climbing.

4. The method in accordance with claim 1 , wherein the change of shape comprises at least one of a deformation, a contraction, a flexing, an undulation and a stretching of the actuatable material of the shape changeable member.

5. The method in accordance with claim 1 , wherein a magnitude of the time varying magnetic field applied is selected in the range of 0 to 500 mT.

6. The method in accordance with claim 5 , wherein the magnitude of the time varying magnetic field applied is varied with a frequency selected in the range of 0 to 1 kHz.

7. The method in accordance with claim 5 , wherein a direction of the time varying magnetic field applied is varied with a frequency selected in the range of 0 to 1 kHz.

8. The method in accordance with claim 1 , further comprising the step of actuating the shape changeable member to additionally carry out at least one function.

9. The method in accordance with claim 8 , wherein the at least one function comprises at least one of a gripping function, a holding function, a dropping function, a clamping function and picking up function.

10. The method in accordance with claim 1 , wherein a type of locomotion of the shape changeable member is selected from the group of members consisting of swimming, walking, flipping, crawling, rolling, diving, immersion, emersion, jumping, landing and climbing,
wherein the change of shape comprises at least one of a deformation, a contraction, a flexing, an undulation and a stretching of the actuatable material of the shape changeable member; and
wherein the shape changeable member is deformed to adopt a sine like or cosine like shape to effect a crawling or walking type of locomotion to enable an undulating locomotion of the shape changeable member; or
wherein the shape changeable member is deformed to adopt a part-circular shape to effect a rolling or meniscus climbing type of locomotion; or
wherein the shape changeable member is deformed to undulate and generate a travelling wave on the member to effect a swimming type of locomotion or crawling type of locomotion, or
wherein the shape of the shape changeable member is flipped from a first shape into a second shape and back into the first shape to effect a jelly-fish swimming type of locomotion; or
wherein the shape changeable member is pulsed with the at least one stimulus in order to effect the jumping type of locomotion; or
wherein to effect an immersion type of locomotion a magnetic field having a rotating B sequence is applied, with the magnetic field effecting a rotation of the shape changeable member in a counter-clockwise sense to reduce a contact with a liquid surface; or
wherein to effect a landing type of locomotion a magnetic field having a rotating B sequence of variable magnitude applied, with the initial B-sequence having a high magnitude which is then reduced to a low magnitude; or
wherein a rocking sequence of the magnetic field is applied to perform the walking type of locomotion; or
wherein to effect a jelly fish-like swimming motion mode of locomotion of the shape changeable member the applied magnetic field is sequentially flipped from a positive magnetic field to a negative magnetic field causing an inversion of the shape of the shape changeable member.

11. A shape changeable member of actuatable material formed from a continuum of infinitesimal segments (ds), with the segments (ds) each comprising the same material but having a different direction of magnetization, the shape changeable member being untethered and having a width, a height and a length, wherein the shape changeable member is configured to be actuated by means of at least one external stimulus present in the form of a time-varying magnetic field applied in at least one dimension in order to bring about a change of shape of the shape changeable member in at least one spatial direction and thereby inducing a torque into the shape changeable member; the shape changeable member being configured to effect a locomotion of the shape changeable member by means of the induced change of shape of the shape changeable member in the at least one spatial direction; and to be moved in the at least one spatial direction in response to the at least one external stimulus.

12. The shape changeable member in accordance with claim 11 , wherein the change of shape comprises at least one of a deformation, a contraction, a flexing and a stretching of the actuatable material of the shape changeable member.

13. The shape changeable member in accordance with claim 11 , wherein the type of locomotion is jumping.

14. The shape changeable member in accordance with claim 11 , wherein the shape changeable member is configured to carry out at least two types of locomotion and the at least two types of locomotion are selected from the group of members consisting of swimming, walking, flipping, crawling, rolling, diving, immersion, emersion, jumping, landing and climbing.

15. An actuating system comprising a shape changeable member in accordance with claim 11 and a magnetic field apparatus, wherein the magnetic field apparatus is a source of the time-varying magnetic field.

16. The actuating system in accordance with claim 15 , wherein the magnetic field apparatus is configured to generate a uniform 3D magnetic field at a center of the system.

17. The actuating system in accordance with claim 15 , wherein the magnetic field apparatus comprises at least two pairs of magnetic coils, wherein each of the pairs of coils is arranged on a common axis, with the respective common axes being arranged at least approximately perpendicular to one another at a center of the system, wherein the shape changeable member is configured to be actuated by means of the pairs of magnetic coils in such a way that the shape changeable member carries out at least one type of locomotion within the applied time-varying magnetic field, and wherein the pairs of magnetic coils are configured to produce the time-varying magnetic field at the center.

Assignees

• Max Planck Gesellschaft

Inventors

• Hu Wenqi
• Zhan Lum Guo
• Mastrangeli Massimo
• Sitti Metin

Classifications

• F03G7/06147

  Magnetic shape memory alloys, e.g. ferro-magnetic alloys · CPC title

• F03G7/064

  characterised by its use · CPC title

• F03G7/0616

  characterised by the material or the manufacturing process, e.g. the assembly (magnetic shape memory alloys F03G7/06147) · CPC title

• F03G7/0614 Primary

  using shape memory elements · CPC title

• F03G7/0612

  using polymers · CPC title