Measuring device for measuring uneveness of a surface of an item

Patent metadata

Field	Value
Publication number	US-11835336-B2
Application number	US-202117764618-A
Country	US
Kind code	B2
Filing date	Jan 22, 2021
Priority date	Jan 24, 2020
Publication date	Dec 5, 2023
Grant date	Dec 5, 2023

Abstract

The present invention relates to a measuring device for characterising a shape of a surface of an item, such as a wind turbine blade fibre layup, wherein the measuring device comprises: a frame comprising a holding frame, a first set of two or more probes movably held in the holding frame, each probe having a respective probe end for contacting the surface of the item, and electronic sensing means configured to provide for each probe a respective electrical signal representative of a position of the probe relative to the holding frame. A method for calibrating such a device is provided. Further, a method for characterising a shape of a surface of an item is provided.

First claim

The invention claimed is:

1. A measuring device ( 40 ) for characterizing a shape of a surface of an item, the measuring device comprising:
a frame comprising a holding frame ( 44 );
a first set of three or more probes ( 41 a - 41 j ) movably held in the holding frame, each of the probes having a respective probe end ( 43 a - 43 j ) for contacting the surface of the item; and
electronic sensing means configured to provide for each of the probes a respective electrical signal representative of a position of the probe relative to the holding frame,
wherein the device is further configured to cause determination of an unevenness signal representative of an unevenness of the surface, the unevenness signal being representative of an angle between 1) a straight line through the probe end of a first probe of the first set of probes and the probe end of a second probe of the first set of probes and 2) a straight line through the probe end of the second probe and the probe end of a third probe of the first set of probes.

2. The measuring device in accordance with claim 1 , wherein each of the probes is connected to biasing means ( 42 a - 42 j ), such as a spring, configured to bias the probe to a corresponding neutral position relative to the holding frame.

3. The measuring device in accordance with claim 2 , wherein each of the probes is connected to corresponding biasing means and each biasing means is connected to a corresponding force sensor configured to provide a corresponding force sensor signal representative of a tension in the corresponding biasing means, and wherein the signal representative of the position of each of the probes is determined based at least in part on the corresponding force sensor signal.

4. The measuring device in accordance with claim 3 , configured to cause determining whether the signal representative of the unevenness of the surface meets an unevenness criterion, and in the affirmative, to cause provision of an unevenness indication.

5. The measuring device in accordance with claim 4 , wherein the unevenness indication comprises an audible signal and/or a visual signal and/or a vibration signal.

6. The measuring device in accordance with claim 1 , configured to cause determining of a signal representative of an unevenness of the surface based on the electrical signals representative of the position of at least two probes in the first set of probes.

7. The measuring device in accordance with claim 1 , configured to cause determining of a signal representative of an unevenness of the surface based at least on 1) the electrical signals representative of the positions of two of the probes relative to the holding frame and 2) a smallest distance between the probe ends of the two probes during measuring.

8. The measuring device in accordance with claim 1 , wherein at least a subset of the first set of probes is arranged in a one-dimensional array.

9. The measuring device in accordance with claim 1 , wherein at least a subset of the first set of probes is arranged in a two-dimensional array.

10. The measuring device in accordance with claim 1 , wherein each of the probes is movably maintained in a respective position by a frictional force exceeding a force corresponding to the standard acceleration of free fall, g0.

11. The measuring device in accordance with claim 1 , wherein the frame further comprises one or more fixed or fixable supporting legs ( 45 a , 45 b ) for supporting the measuring device on the surface of the item during obtaining of the electrical signals representative of the positions of the probes relative to the holding frame ( 44 ).

12. A method for calibrating a device in accordance with claim 11 , the method comprising:
placing the device on the one or more supporting legs on a surface and storing reference information including storing a reference signal representative of the electrical signal provided by the electronic sensing means for each of the probes in a second set of one or more of the probes in the first set of probes, such as all the probes in the first set of probes, and during subsequent use, determining for at least one probe in the second set of probes, such as for each of all the probes in the second set of probes, a signal representative of a difference between the electrical signal measured during said use and the corresponding reference signal.

13. The measuring device in accordance with claim 1 , wherein the device is configured such that a weight of the frame exceeds a maximum total force that the first set of probes can exert on a first portion of a surface while the supporting legs are in contact with a second portion of said surface.

14. The measuring device in accordance with claim 1 , wherein the probe ends of two probes of the first set of probes are separated by a distance of at least 10 cm.

15. The measuring device in accordance with claim 1 , operable to communicate to an external device a signal representative of the electrical signals corresponding to at least two of the probes, and/or
a signal representative of an unevenness of the surface of the item determined based on the electrical signals representative of the positions of at least two of the probes.

16. The measuring device in accordance with claim 1 , wherein the electrical signals corresponding to at least two of the probes are obtained using corresponding linear variable differential transformers or based on respective resistance measurements.

17. A method for characterizing a shape of a surface of an item, comprising:
providing three or more probes movably held in a holding frame, each of the probes having a corresponding probe end for contacting the surface of the item;
bringing at least three of the probe ends into contact with the surface of the item;
obtaining electrical signals representative of corresponding positions of at least two of the probes relative to the holding frame; and
determining an unevenness signal representative of an unevenness of the surface, the unevenness signal being representative of an angle between 1) a straight line through the probe end of a first probe of the first set of probes and the probe end of a second probe of the first set of probes and 2) a straight line through the probe end of the second probe and the probe end of a third probe of the first set of probes.

18. The method in accordance with claim 17 , further comprising obtaining the respective electrical signals at least when the holding frame is at a first position relative to the item and when the holding frame is at a second position relative to the item different from the first position.

19. The method in accordance with claim 18 , further comprising moving the holding frame from the first position to the second position while at least two of the probes are in contact with the surface of the item.

20. The method in accordance with claim 17 , further comprising:
determining an unevenness signal representative of an unevenness of the surface of the item based on the electrical signals representative of the positions of at least two of the probes relative to the holding frame.

21. The method in accordance with claim 17 , further comprising determining whether the unevenness signal representative of an unevenness of the surface meets an unevenness criterion, and generating an unevenness indication when the unevenness signal meets the unevenness criterion.

22. The method in accordance with claim 21 , wherein the unevenness indication comp

Assignees

• Lm Wind Power As

Inventors

• Kildegaard Casper
• Jørgensen Ya Min

Classifications

• G01B5/207 Primary

  using a plurality of fixed, simultaneously operating transducers (G01B5/213 - G01B5/22 take precedence) · CPC title

• G01B5/285

  for controlling eveness · CPC title

• B29C70/54

  Component parts, details or accessories; Auxiliary operations {, e.g. feeding or storage of prepregs or SMC after impregnation or during ageing} · CPC title

• B29L2031/085

  Wind turbine blades · CPC title