Systems and methods for photophoretic propulsion for flight

Patent metadata

Field	Value
Publication number	US-2022380039-A1
Application number	US-202217742887-A
Country	US
Kind code	A1
Filing date	May 12, 2022
Priority date	May 12, 2021
Publication date	Dec 1, 2022
Grant date	—

Abstract

Systems and methods for achieving levitation via a photophoretic effect are provided. In certain embodiments, a structure of ultralight materials is provided, for example a BoPET film and carbon nanotubes and has a top and bottom side, made of two separate materials. When the bottom side is illuminated by light at certain intensity, it can result in an upward lift force being applied to the entire structure, causing the structure to levitate.

First claim

What is claimed is:

1 . A system for achieving photophoretic levitation, comprising:
a structure having a top side and a bottom side; wherein the top side comprises a first material configured to reflect a portion of incident particles without trapping the particles; and wherein the bottom side comprises a second material configured to trap incident particles for a first time period.

2 . The system of claim 1 , wherein the top side comprises a biaxially-oriented polyethylene terephthalate (BoPET) film.

3 . The system of claim 1 , wherein the bottom side comprises one or more carbon nanotubes.

4 . The system of claim 2 , wherein the BoPET sheet has a thickness of approximately 500 nanometers.

5 . The system of claim 1 , wherein the bottom side has a thickness of approximately 300 nanometers.

6 . The system of claim 2 , wherein the one or more carbon nanotubes each have a diameter between 1 to 2 nanometers and a length between 5 and 30 micrometers.

7 . The system of claim 1 , wherein the structure comprises a disk.

8 . The system of claim 7 , wherein the disk has a diameter of approximately 6 millimeters.

9 . The system of claim 1 , wherein the second material is configured to provide rigidity to the structure.

10 . The system of claim 1 , wherein the second materials is a light absorber with a visible-range absorptivity of greater than 80%.

11 . The system of claim 1 , further comprising one or more components attached to the structure.

12 . The system of claim 2 , wherein the top side further comprises a layer of aluminum oxide deposited onto the BoPET film using atomic layer deposition.

13 . The system of claim 11 , wherein the one or more components include at least a temperature sensor.

14 . The system of claim 11 , wherein the one or more components include at least a camera.

15 . A method of using a structure for achieving photophoretic levitation, comprising:
providing a structure having a top side and a bottom side; illuminating the bottom side of the structure with electromagnetic radiation within a predetermined frequency range maintaining the structure at a predetermined altitude using the electromagnetic radiation.

16 . The method of claim 15 , wherein the predetermined frequency of the electromagnetic radiation is in the visible light spectrum.

17 . The method of claim 15 , wherein the structure comprises a BoPET film and a plurality of carbon nanotubes.

18 . The method of claim 15 , further comprising:
varying an intensity of the electromagnetic radiation in order to modulate the altitude reached by the structure.

19 . The method of claim 15 , wherein the structure further comprises one or more components, further comprising:
deploying the one or more components when the structure reaches the altitude.

20 . The method of claim 15 , wherein the altitude is between 50 and 100 kilometers above sea level.

21 . The method of claim 15 , wherein the altitude is less than or equal to 50 kilometers.

22 . The method of claim 17 , wherein the structure further comprises an aluminum oxide layer deposited onto the BoPET film using atomic layer deposition.

Assignees

• Univ Pennsylvania

Inventors

• Bargatin Igor
• Lu Zhipeng
• Azadi Mohsen

Classifications

• C08J7/06 Primary

  with compositions not containing macromolecular substances · CPC title

• C08J2367/02

  Polyesters derived from dicarboxylic acids and dihydroxy compounds; (C08J2367/06 takes precedence) · CPC title

• B64B1/00

  Lighter-than-air aircraft · CPC title

• B64C39/00 Primary

  Aircraft not otherwise provided for · CPC title

• C08J5/18

  Manufacture of films or sheets · CPC title