# US 2025/0164640 A1 · System and Method for Sensing Underwater Point Cloud > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2025/0164640 A1 - Document ID: US20250164640A1 - Status: Published application - Kind: A1 - Application number: 18/755,657 - Filed: 2024-06-26 - Published: 2025-05-22 - Earliest claimed: 2023-11-21 - Assignees: Metal Industries Research & Development Centre - Applicants: Metal Industries Research & Development Centre - Inventors: Wei-Te CHEN; Shang-Ching CHUANG; Chen-Shun CHEN; Pin-Xian LIN; Chen-Han KUO; Yun-Hui HE; Yao-Ming WANG - Web page: https://patentgrep.com/patent/US20250164640A1 ## CPC - G01S 15/89: for mapping or imaging - G01S 7/52004: {Means for monitoring or calibrating (short-range imaging G01S7/5205)} - G01S: RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES ## Abstract The present invention proposes a method for sensing underwater point cloud. The method includes: acquiring point cloud information through an underwater sonar array, where the point cloud information contains multiple points; rearranging these points into a matrix which includes the aforementioned points and multiple missing points; and for each missing point, interpolating its depth value based on the depth values of several neighboring points. ## Claims ### Claim 1 A system for sensing underwater point cloud, comprising: an underwater sonar array configured to acquire point cloud information comprising a plurality of points; and a computing module communicatively connected to the underwater sonar array, wherein the computing module is configured to rearrange the points into a matrix comprising the points and a plurality of missing points; wherein the computing module performs an interpolation calculation for each of the missing points based on depth values of neighboring points among the points to obtain a depth value of each of the missing points. ### Claim 2 (depends on 1) The system of claim 1, wherein the computing module redetermines a X-coordinate and a Y-coordinate of one of the points based on an arrangement direction of sensors of the underwater sonar array. ### Claim 3 (depends on 2) The system of claim 2, wherein the computing module performs the interpolation calculation to obtain the depth value of each of the missing points based on the following equation 1: Z = ∑ i = 1 n ⁢ Z i r i p ∑ i = 1 n ⁢ 1 r i p [ Equation ⁢ 1 ] wherein Z is the depth value of one of the missing point, i is a positive integer, n is a number of the neighboring points, rip is a distance between one of the neighboring points and the one of the missing point, and Zi is a depth value of one of the neighboring points. ### Claim 4 (depends on 3) The system of claim 3, wherein the computing module is further configured to calculate an interpolation depth corresponding to one of the missing points based on a thin plate spline interpolation algorithm, and to calculate an average value of the interpolation depth and the depth value Z to compensate the corresponding missing point. ### Claim 5 (depends on 4) The system of claim 4, further comprising: an image sensor configured to capture a digital image comprising a plurality of pixels, wherein each of the pixels comprises a red gray value, a green gray value and a blue gray value, and the computing module is configured to calibrate a depth value of one of the missing points based on the following equation 2: P C = P ″ + [ ( ( R ″ - R a ⁢ v ⁢ g ) × W R ⁢ C ) + ( ( G ″ - G a ⁢ v ⁢ g ) × W G ⁢ C ) + ( ( B ″ - B a ⁢ v ⁢ g ) × W B ⁢ C ) ] ⁢ W R ⁢ C = R a ⁢ v ⁢ g 1 P ″ ⁢ W G ⁢ C = G a ⁢ v ⁢ g 1 P ″ ⁢ W B ⁢ C = B a ⁢ v ⁢ g 1 P ″ [ Equation ⁢ 2 ] wherein PC is a calibrated depth value, P″ is the depth value of the one of the missing points, R″ is the red gray value of the one of the missing points, G″ is the green gray value of the one of the missing points, B″ is the blue gray value of the one of the missing points, Ravg is an average red gray value of a plurality of similar pixels among the pixels, Gavg is an average green gray value of the similar pixels among the pixels, and Bavg is an average blue gray value of the similar pixels among the pixels. ### Claim 6 (depends on 5) The system of claim 5, wherein the point cloud information corresponds to an area of steep slope. ### Claim 7 (depends on 5) The system of claim 5, wherein the point cloud information corresponds to a side of an object. ### Claim 8 A method for sensing underwater point cloud, executed by a computer system, wherein the method for sensing underwater point cloud comprises: acquiring point cloud information through an underwater sonar array, wherein the point cloud information comprises a plurality of points; rearranging the points into a matrix comprising the points and a plurality of missing points; and performing an interpolation calculation for each of the missing points based on depth values of neighboring points among the points to obtain a depth value of each of the missing points. ### Claim 9 (depends on 8) The method of claim 8, wherein rearranging the points into the matrix comprises: redetermining a X-coordinate and a Y-coordinate of one of the points based on an arrangement direction of sensors of the underwater sonar array. ### Claim 10 (depends on 9) The method of claim 9, wherein performing the interpolation calculation to obtain the depth value of each of the missing points is based on the following equation 1: Z = ∑ i = 1 n ⁢ Z i r i p ∑ i = 1 n ⁢ 1 r i p [ Equation ⁢ 1 ] wherein Z is the depth value of one of the missing point, i is a positive integer, n is a number of the neighboring points, rip is a distance between one of the neighboring points and the one of the missing point, and Zi is a depth value of one of the e neighboring points. ### Claim 11 (depends on 10) The method of claim 10, further comprising: calculating an interpolation depth corresponding to one of the missing points based on a thin plate spline interpolation algorithm, and calculating an average value of the interpolation depth and the depth value Z to compensate the corresponding missing point. ### Claim 12 (depends on 11) The method of claim 11, further comprising: capturing a digital image through an image sensor, wherein the digital image comprises a plurality of pixels, each of the pixels comprises a red gray value, a green gray value and a blue gray value, and calibrating a depth value of one of the missing points based on the following equation 2: P C = P ″ + [ ( ( R ″ - R a ⁢ v ⁢ g ) × W R ⁢ C ) + ( ( G ″ - G a ⁢ v ⁢ g ) × W G ⁢ C ) + ( ( B ″ - B a ⁢ v ⁢ g ) × W B ⁢ C ) ] ⁢ W R ⁢ C = R a ⁢ v ⁢ g 1 P ″ ⁢ W G ⁢ C = G a ⁢ v ⁢ g 1 P ″ ⁢ W B ⁢ C = B a ⁢ v ⁢ g 1 P ″ [ Equation ⁢ 2 ] wherein PC is a calibrated depth value, P″ is the depth value of the one of the missing points, R″ is the red gray value of the one of the missing points, G″ is the green gray value of the one of the missing points, B″ is the blue gray value of the one of the missing points, Ravg is an average red gray value of a plurality of similar pixels among the pixels, Gavg is an average green gray value of the similar pixels among the pixels, and Bavg is an average blue gray value of the similar pixels among the pixels. ### Claim 13 (depends on 10) The method of claim 10, further comprising: performing a down sampling process on the digital image to allow the pixels of the digital image to be corresponded by the points of the point cloud information in a one-to-one manner. ### Claim 14 (depends on 10) The method of claim 10, wherein the point cloud information corresponds to an area of steep slope. ### Claim 15 (depends on 10) The method of claim 10, wherein the point cloud information corresponds to a side of an object.