# US 11,999,480 B2 · Flight control system for unmanned aerial vehicle and topography measuring system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,999,480 B2 - Document ID: US11999480B2 - Status: Granted - Kind: B2 - Application number: 17/781,832 - Filed: 2020-12-03 - Published: 2023-01-12 - Granted: 2024-06-04 - Earliest claimed: 2019-12-05 - Assignees: Topcon Corporation; Tierra S.P.A. - Applicants: TOPCON Corporation; Tierra S.p.A - Inventors: Riccardo Loti; Kaoru Kumagai - Web page: https://patentgrep.com/patent/US11999480B2 ## CPC - G01C 15/002: {Active optical surveying means (optical plumbing G01C15/105)} - B64D 47/08: Arrangements of cameras - G01C 11/02: Picture taking arrangements specially adapted for photogrammetry or photographic surveying, e.g. controlling overlapping of pictures - G01S 17/66: Tracking systems using electromagnetic waves other than radio waves - G05D 1/101: {specially adapted for aircraft} - G05D 1/46: Control of position or course in three dimensions [3D] - B64U 2101/32: for cartography or topography - B64U 2201/00: UAVs characterised by their flight controls - B64U 2201/104: using satellite radio beacon positioning systems, e.g. GPS - G01C: MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY (measuring liquid level G01F; radio navigation, determining distance or velocity by use of propagation effects, e.g. Doppler effects, propagation time, of radio waves, analogous arrangements using other waves G01S) - B64D: EQUIPMENT FOR FITTING IN OR TO AIRCRAFT; FLIGHT SUITS; PARACHUTES; ARRANGEMENT OR MOUNTING OF POWER PLANTS OR PROPULSION TRANSMISSIONS IN AIRCRAFT - 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 - G05D: SYSTEMS FOR CONTROLLING OR REGULATING NON-ELECTRIC VARIABLES - B64U: UNMANNED AERIAL VEHICLES [UAV]; EQUIPMENT THEREFOR ## Abstract A flight control system for an unmanned aerial vehicle comprises an unmanned aerial vehicle on which a reflector is mounted and a total station for tracking the reflector and for acquiring measurement data including three-dimensional coordinates of the reflector, wherein the total station comprises a tracking module for tracking the reflector, a TS-data transmitting module having an optical axis parallel or approximately parallel to a tracking optical axis of the tracking module and for emitting a TS-data transmitting light, and a TS-arithmetic control module, wherein the unmanned aerial vehicle has a photodetector for receiving the TS-data transmitting light and for emitting a photodetecting signal and a UAV-arithmetic control module for controlling a flight of the unmanned aerial vehicle, and wherein the TS-arithmetic control module is configured to superimpose the measurement data on the TS-data transmitting light, and the UAV-arithmetic control module is configured to separate the measurement data from the photodetecting signal and obtains a flight position of the unmanned aerial vehicle in real time. ## Claims ### Claim 1 A flight control system for an unmanned aerial vehicle comprising an unmanned aerial vehicle on which a reflector is mounted and a total station for tracking said reflector and for acquiring measurement data including three-dimensional coordinates of said reflector, wherein said total station emits a tracking light along a tracking optical axis, a distance measuring light and a TS-data transmitting light, and wherein the total station irradiates the tracking light toward said reflector, receives a reflected tracking light from said reflector and performs a tracking of said reflector based on a photodetection position of the reflected tracking light on a photodetector, wherein the total station has an optical axis parallel or approximately parallel to the tracking optical axis for emitting the TS-data transmitting light, and a TS-arithmetic control module, wherein said total station is configured to pulse-emit said tracking light in a predetermined cycle, and has a tracking photodetection shutter which restricts or inhibits a photodetection of the reflected tracking light, wherein said tracking photodetection shutter permits light to be received for a predetermined time from the emission timing of the tracking light, wherein said total station is configured to emit said TS-data transmitting light in a time period from an end of said predetermined time to when a next tracking light is emitted in such a manner that said TS-data transmitting light, said tracking light and said reflected tracking light do not interfere with each other, wherein said unmanned aerial vehicle has a photodetector for receiving said TS-data transmitting light and for emitting a photodetecting signal and a UAV-arithmetic control module for controlling a flight of said unmanned aerial vehicle, and wherein said TS-arithmetic control module is configured to superimpose said measurement data on said TS-data transmitting light, and said UAV-arithmetic control module is configured to separate said measurement data from said photodetecting signal and to obtain a flight position of said unmanned aerial vehicle in real time. ### Claim 2 (depends on 1) The flight control system for the unmanned aerial vehicle according to claim 1, wherein said UAV-arithmetic control module is configured to control the flight of said unmanned aerial vehicle based on three-dimensional coordinates included in said measurement data. ### Claim 3 (depends on 1) The flight control system for the unmanned aerial vehicle according to claim 1, wherein the tracking light is emitted as said TS-data transmitting light in the time period of each emission interval. ### Claim 4 (depends on 1) The flight control system for the unmanned aerial vehicle according to claim 1, wherein said photodetector includes said reflector and has a reflective film formed on a reflection surface of said reflector and for transmitting a part of a light, and a photodetection element for receiving said TS-data transmitting light through said reflective film. ### Claim 5 A topography measuring system comprising: an unmanned aerial vehicle, on which a reflector and a shape measuring instrument provided at a position known to said reflector are mounted, and a total station for tracking said reflector and for acquiring measurement data including three-dimensional coordinates of said reflector, wherein said total station emits a tracking light along a tracking optical axis, a distance measuring light and a TS-data transmitting light, and wherein the total station irradiates a tracking light along a tracking optical axis toward said reflector, receives a reflected tracking light from said reflector and performs a tracking of said reflector based on a photodetection position of the reflected tracking light on a photodetector, the total station having an optical axis parallel or approximately parallel to the tracking optical axis for emitting a TS-data transmitting light, and a TS-arithmetic control module, wherein said total station is configured to pulse-emit said tracking light in a predetermined cycle, and has a tracking photodetection shutter which restricts or inhibits a photodetection of the reflected tracking light, wherein said tracking photodetection shutter permits light to be received for a predetermined time from the emission timing of the tracking light, wherein said total station is configured to emit said TS-data transmitting light in a time period from an end of the predetermined time to when a next tracking light is emitted in such a manner that said TS-data transmitting light, said tracking light and said reflected tracking light do not interfere with each other, wherein said unmanned aerial vehicle has a photodetector for receiving said TS-data transmitting light and for emitting a photodetecting signal and a UAV-arithmetic control module for controlling a flight of said unmanned aerial vehicle, and wherein said TS-arithmetic control module is configured to superimpose said measurement data on said TS-data transmitting light, said UAV-arithmetic control module is configured to acquire topographical shape data by said shape measuring instrument, and said UAV-arithmetic control module is configured to separate said measurement data from said photodetecting signal, to obtain a position of said shape measuring instrument in real time, to associate the position of said shape measuring instrument with said topographical shape data, and to obtain three-dimensional coordinates of said shape measuring instrument at the time of acquiring said topographical shape data. ### Claim 6 (depends on 5) The topography measuring system according to claim 5, wherein said UAV-arithmetic control module is configured to control the flight of said unmanned aerial vehicle based on three-dimensional coordinates included in said measurement data. ### Claim 7 (depends on 5) The topography measuring system according to claim 5, wherein said total station is configured to pulse-emit a tracking light in a predetermined cycle and to emit said TS-data transmitting light in a time period of each emission interval in such a manner that said TS-data transmitting light does not interfere with the tracking light and a reflected tracking light. ### Claim 8 (depends on 7) The topography measuring system according to claim 7, wherein the tracking light is emitted as said TS-data transmitting light in the time period of each emission interval. ### Claim 9 (depends on 5) The topography measuring system according to claim 5, wherein said photodetector includes said reflector and has a reflective film formed on a reflection surface of said reflector and for transmitting a part of a light, and a photodetection element for receiving said TS-data transmitting light through said reflective film. ### Claim 10 (depends on 5) The topography measuring system according to claim 5, wherein said total station has a TS-GNSS device, said unmanned aerial vehicle has a UAV-GNSS device, wherein said TS-arithmetic control module is configured to obtain a GNSS time at the time of acquiring said measurement data by said TS-GNSS device and to associate said GNSS time with said measurement data, and wherein said UAV-arithmetic control module is configured to obtain a GNSS time at the time of acquiring shape data by said UAV-GNSS device, to associate said GNSS time with said shape data, and to associate said measurement data with said shape data through said GNSS time. ### Claim 11 (depends on 5) The topography measuring system according to claim 5, wherein said shape measuring instrument is a camera for photographing a ground surface, and said UAV-arithmetic control module is configured to perform a photogrammetry based on image data acquired by said camera and on three-dimensional coordinates, as obtained from said TS-data transmitting light, of said camera at the time of acquiring an image. ### Claim 12 (depends on 5) The topography measuring system according to claim 5, wherein said shape measuring instrument is a laser scanner for acquiring point cloud data, and said UAV-arithmetic control module is configured to convert said point cloud data into three-dimensional data of a ground surface system based on said point cloud data acquired by said laser scanner and on three-dimensional coordinates, as obtained from said TS-data transmitting light, of said laser scanner at the time of acquiring said point cloud data. ### Claim 13 A topography measuring system comprising: an unmanned aerial vehicle, on which a reflector and a shape measuring instrument provided at a position known to said reflector are mounted, and a total station for tracking said reflector and for acquiring measurement data including three-dimensional coordinates of said reflector, wherein said total station emits a tracking light along a tracking optical axis, a distance measuring light and a TS-data transmitting light, and wherein the total station irradiates a tracking light toward said reflector, receives a reflected tracking light from said reflector and performs a tracking of said reflector based on a photodetection position of the reflected tracking light on a photodetector, and a TS-arithmetic control module, wherein said total station is configured to pulse-emit said tracking light in a predetermined cycle, and has a tracking photodetection shutter which restricts or inhibits a photodetection of the reflected tracking light, wherein said tracking photodetection shutter permits light to be received for a predetermined time from the emission timing of the tracking light, wherein said unmanned aerial vehicle has a UAV-data transmission module for emitting a UAV-data transmitting light and a UAV-arithmetic control module for controlling the flight of said unmanned aerial vehicle, wherein said UAV-arithmetic control module is configured to acquire shape data by said shape measuring instrument and to superimpose said shape data on said UAV-data transmitting light, and said TS-arithmetic control module is configured to acquire said shape data from said UAV-data transmitting light, to associate said shape data with the measurement data, and to acquire three-dimensional coordinates of said shape measuring instrument at the time of acquiring said shape data. ### Claim 14 (depends on 13) The topography measuring system according to claim 13, wherein said total station has a TS-GNSS device, said unmanned aerial vehicle has a UAV-GNSS device, said UAV-arithmetic control module is configured to acquire a GNSS time at the time of acquiring said shape data by said UAV-GNSS device and to associate said GNSS time with said shape data, and said TS-arithmetic control module is configured to acquire a GNSS time at the time of acquiring said measurement data by said TS-GNSS device, to associate said GNSS time with said measurement data, and associate said measurement data with said shape data through said GNSS time. ### Claim 15 (depends on 13) The topography measuring system according to claim 13, wherein said shape measuring instrument is a camera for photographing a land surface, and said TS-arithmetic control module is configured to acquire three-dimensional coordinates of said camera at the time of acquiring an image based on said measurement data and to perform a photogrammetry from the image data and said three-dimensional coordinates. ### Claim 16 (depends on 13) The topography measuring system according to claim 13, wherein said shape measuring instrument is a laser scanner for acquiring point cloud data of a land surface, and said TS-arithmetic control module is configured to convert said point cloud data into the three-dimensional data of the land surface system based on said point cloud data and three-dimensional coordinates of said laser scanner as obtained from said measurement data at the time of acquiring said point cloud data. ### Claim 17 (depends on 10) The topography measuring system according to claim 10, wherein said shape measuring instrument is a camera for photographing a ground surface, and said UAV-arithmetic control module is configured to perform a photogrammetry based on image data acquired by said camera and on three-dimensional coordinates, as obtained from said TS-data transmitting light, of said camera at the time of acquiring an image. ### Claim 18 (depends on 10) The topography measuring system according to claim 10, wherein said shape measuring instrument is a laser scanner for acquiring point cloud data, and said UAV-arithmetic control module is configured to convert said point cloud data into three-dimensional data of a ground surface system based on said point cloud data acquired by said laser scanner and on three-dimensional coordinates, as obtained from said TS-data transmitting light, of said laser scanner at the time of acquiring said point cloud data.