Digital forest compass and measuring system

Abstract

The utility model discloses a digital forest compass, and belongs to the technical field of forest resource investigation. Comprising a measuring device integrated with a single-point ranging radar, an attitude sensor and an industrial camera; and the tablet computer is connected with the measuring device and is used for processing, recording and storing the data extracted by the measuring device. The utility model also discloses a digital forest compass measurement system, which comprises measurement hardware which is the digital forest compass; and the measuring software consists of embedded software and PC (Personal Computer) end software. The whole device is small in size, convenient to carry and capable of being operated by one person; compared with a traditional measuring instrument, data does not need to be manually recorded, input and corrected, real-time images and virtual sight beads presented by the industrial camera on software replace a sighting telescope of a traditional compass for target alignment, and efficiency is greatly improved. In an efficiency measurement test, the measurement efficiency of the instrument is twice that of a traditional instrument.

Description

Technical Field

[0001] The utility model belongs to the technical field of forest resource investigation, and in particular relates to a digital forest compass and a measuring system. Background Art

[0002] Tree height and tree position are basic parameters in standing tree measurement factors, and are often used to estimate parameters such as forest growth, tree age, timber volume, biomass and carbon storage. They are very important survey factors in the continuous inventory of forest resources in my country. The continuous inventory of forest resources can collect forest attributes and provide a basis for decision makers at different levels to manage forests and formulate afforestation plans. Accurate, detailed and reliable forest resource information plays a vital role in helping forestry authorities and forestry production and management units at different levels to grasp the status of forest resources and their changing patterns, formulate sustainable development policies, plan forest management plans and forest management, etc. It also lays a data foundation for models such as forest ecological assessment, fire prevention and carbon storage estimation.

[0003] With the development of technologies such as sensors, computers, and satellite remote sensing, the concepts and theories of forestry informatization, forestry digitization, and forestry intelligence have been proposed and continuously improved. A large number of experts and scholars at home and abroad have proposed or developed many emerging measurement methods or observation instruments, trying to replace the traditional forest compass, such as:

[0004] 1. Kong Lei and others developed a mechanical electronic forest compass to measure plot perimeters, tree heights, and tree coordinates. The instrument achieved an accuracy of 0.3°, 0.03m, and 0.06m in azimuth, altitude, and horizontal distance, respectively.

[0005] 2. Liu Xianlun and others conducted an application study on the TC01 intelligent forest compass in the first-class forest resource inventory and found that the intelligent compass is more accurate and efficient than the traditional forest compass, and the work intensity is significantly reduced;

[0006] 3. Zhao Ziyu and others developed an ultra-wideband positioning photogrammetric tree measuring instrument with real-time positioning function and forest stand photogrammetry function. The measurement value deviation of the instrument in the standing tree position is -0.16~0.27cm, and the root mean square error is 0.23~0.34m.

[0007] 4. Fan Yongxiang et al. designed a LiDARSLAM forest plot survey system based on the LOAM algorithm and Velodyne VLP-32C laser radar. The average errors of the estimated standing tree positions in the x- and y-axis directions were -0.004m and -0.011m, respectively, and the root mean square errors in the x- and y-axis directions were 0.081m and 0.083m, respectively.

[0008] 5. Wang Zhichao and others designed a professional tree measurement program and proposed an integrated indoor and outdoor solution for tree measurement total stations, in order to promote the use of total stations for tree measurement.

[0009] However, the above methods or instruments generally have problems such as high cost, complicated operation, difficulty in carrying (large size and heavy weight), and poor compatibility between hardware and software. Utility Model Content

[0010] The utility model aims at the above problems existing in the prior art and proposes a digital forest compass and a measuring system which integrates data uploading, processing, recording and storing functions and can measure tree positions and tree heights.

[0011] The utility model can be realized through the following technical solutions:

[0012] A digital forest compass, comprising:

[0013] A measuring device, which integrates a single-point ranging radar, a posture sensor and an industrial camera, wherein the single-point ranging radar is used for ranging, the posture sensor is used for determining the position angle, and the industrial camera is used for providing real-time image-assisted description;

[0014] A tablet computer is connected to the measuring device and is used to process, record and store the data extracted by the measuring device.

[0015] As a further improvement of the present invention, the measuring device includes a mounting bracket, the tablet computer is mounted on the mounting bracket, and the single-point ranging radar, the attitude sensor and the industrial camera are integrated into the mounting bracket.

[0016] As a further improvement of the present utility model, the industrial camera is integrated with an image sensor, and the image sensor and the single-point ranging radar are located on the same surface of the mounting bracket.

[0017] As a further improvement of the present invention, the tablet computer and the single-point ranging radar are respectively located on the front and rear surfaces of the mounting bracket.

[0018] As a further improvement of the present utility model, the posture sensor comprises:

[0019] An acceleration sensor is used to measure the gravitational acceleration components Ax, Ay, and Az of the x, y, and z axes;

[0020] The magnetometer is used to calculate the heading angle N by combining the three-axis gravity acceleration components measured by the acceleration sensor with the pitch angle P and the roll angle R.

[0021] As a further improvement of the utility model, the measuring device also integrates a single-chip microcomputer, a chip, a USB-HUB module and a storage unit.

[0022] As a further improvement of the utility model, a tripod is provided at the bottom of the mounting bracket.

[0023] A digital forest compass measurement system, comprising:

[0024] The measurement hardware is configured as the digital forest compass described above;

[0025] The measurement software consists of embedded software and PC software, among which:

[0026] The embedded software is used to extract the data of the single-point ranging radar and the attitude sensor and encode them before uploading them to the tablet computer;

[0027] The PC software is configured as a multi-threaded structure and is used to provide data processing, visualization and user interaction functions.

[0028] As a further improvement of the present invention, the embedded software includes:

[0029] The main thread is used to provide user interface display and control logic;

[0030] A serial port communication thread, used for data communication with the embedded software;

[0031] The image processing thread is used to perform image processing and analysis using the image data collected by the industrial camera.

[0032] Compared with the prior art, the utility model has the following beneficial effects:

[0033] 1. Portability and single-person operation: The instrument is small in size and designed for the convenience of field work. It is easy to carry, so that a single person can complete the measurement work independently without the need for teamwork, thus reducing manpower requirements;

[0034] 2. Automated data processing: Compared with traditional measurements that require hand-written records, manual entry and proofreading of data, the digital compass automatically processes data through integrated software, greatly reducing manual intervention, improving work efficiency and avoiding human errors;

[0035] 3. Real-time visual assistance: The innovative introduction of industrial cameras and virtual crosshairs replaces the traditional sights. Surveyors can directly aim at trees through real-time images and virtual crosshairs in the software interface. This is intuitive, fast and accurate, improving the efficiency of aiming.

[0036] 4. Significant efficiency improvement: Efficiency tests show that the measurement efficiency of the new compass is twice that of traditional equipment, proving its significant performance advantages in practical applications;

[0037] 5. Information tools: As a new information measurement tool, the digital forest compass has brought innovation to forest resource inventory work. Its real-time data collection, processing and management are in line with the trend of modern forestry intelligence and informationization;

[0038] 6. Broad application prospects: In view of its high efficiency, accuracy, convenience and information-based characteristics, the digital compass is expected to become a new standard for continuous inventory of forest resources, and will be widely used in forestry resource assessment, afforestation planning, forest management, ecological monitoring, fire warning and carbon reserve estimation, etc., providing strong technical support for modern forestry management and promoting the practice of sustainable development strategies in forestry. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a structural schematic diagram of the digital forest compass of the utility model;

[0040] Figure 2 It is a circuit connection principle diagram of the utility model.

[0041] In the figure, 100 is a measuring device; 110 is a single-point ranging radar; 120 is a posture sensor; 130 is an industrial camera; 131 is an image sensor; 140 is a mounting bracket; 150 is a tripod; and 200 is a tablet computer. DETAILED DESCRIPTION

[0042] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical method of the present invention, but the present invention is not limited to these embodiments.

[0043] like Figure 1-2 As shown, the utility model provides a digital forest compass, comprising:

[0044] The measuring device 100 integrates a single-point ranging radar 110, a posture sensor 120 and an industrial camera 130. The single-point ranging radar 110 uses ToF (Time of Fl ight) technology to measure the distance between the instrument and the target (tree) by calculating the round-trip time of light, which is the key to tree height measurement.

[0045] The attitude sensor 120 measures the tilt attitude of the device, including the pitch angle, roll angle and heading angle, to ensure the accuracy of position measurement;

[0046] The industrial camera 130 provides real-time image feedback, replacing the traditional sight, allowing the operator to directly aim at the tree through the virtual crosshairs in the software interface, which improves the convenience and intuitiveness of operation;

[0047] Tablet computer 200 is connected to measuring device 100 via USB and is used to process, record and store data extracted by measuring device 100. It runs customized C# software with the following functions:

[0048] 1. Data processing: receiving and analyzing the original data such as distance and angle transmitted by the measuring device 100;

[0049] 2. Real-time display: The real-time image of the industrial camera 130 is displayed on the screen, and a virtual crosshair is superimposed to help accurately aim at the tree;

[0050] 3. Data recording and storage: The processed measurement results are recorded and stored locally for easy management and export to Excel and other formats for further analysis or report production.

[0051] Preferably, the measuring device 100 includes a mounting bracket 140, and the mounting bracket 140 is stably placed on the ground through a tripod 150 at the bottom, wherein the tablet computer 200 is mounted on the mounting bracket 140, and the single-point ranging radar 110, the attitude sensor 120 and the industrial camera 130 are integrated in the mounting bracket 140;

[0052] That is to say, all key components are integrated on the same mounting bracket 140. This design ensures the integration of the equipment, which is not only easy to carry, but also reduces the complexity of installation and operation, so that the entire system can be quickly deployed and disassembled when working in the field.

[0053] Preferably, the industrial camera 130 is integrated with an image sensor 131, and the image sensor 131 and the single-point ranging radar 110 are located on the same surface of the mounting bracket 140, wherein the image sensor 131 has the following functions:

[0054] 1. Real-time imaging: The image sensor 131 is integrated into the industrial camera 130, which can capture real-time images of the forest scene and provide instant visual feedback to the operator. Through the images displayed by the software, the surveyor can intuitively observe the current position of the trees without relying on traditional optical sights, which improves the accuracy and ease of use of aiming;

[0055] 2. Assisted measurement: During the measurement of tree position and height, the images captured by the image sensor 131 are used in combination with the virtual crosshairs to replace the physical sights, helping surveyors to accurately aim at the chest height or top of the tree and achieve rapid positioning, which is crucial to improving measurement efficiency and reducing errors.

[0056] 3. Environmental monitoring: In addition to direct measurement purposes, image data can also record the conditions of trees and their surrounding environment, including vegetation cover, understory structure, etc. This information is valuable for later analysis such as forest ecological assessment and pest and disease monitoring;

[0057] 4. Convenient for data recording and analysis: The images captured by the image sensor 131 can be stored as raw data, which is convenient for subsequent review and verification or further image processing and analysis, such as tree diameter and growth form recognition, providing more dimensional information support for forest resource management.

[0058] Preferably, the tablet computer 200 and the single-point ranging radar 110 are respectively located on the front and rear sides of the mounting bracket 140. Such a layout design enables the operator to observe and operate directly through the screen of the tablet computer 200 without using an external aiming device. The tablet computer 200 not only displays the real-time distance information measured by the single-point ranging radar 110, but also displays the north angle of the electronic compass and the real-time image captured by the industrial camera 130, which includes a virtual crosshair to assist the operator in accurately aiming at a specific position of the target tree, such as chest height or the top of the tree.

[0059] Specifically, the measurement principle of tree positions is as follows:

[0060] 1. Instrument deployment: First, place the digital forest compass in the center of the plot to ensure that it covers all trees within the plot.

[0061] 2. Measure one by one: measure each tree in the plot in the established order until all trees are measured;

[0062] 3. Precise alignment: For each tree, the operator needs to use the virtual crosshairs on the software interface to align the tree at breast height, which is usually the height of the tree's diameter at breast height, about 1.3 meters. The crosshairs help to accurately align the target and ensure the accuracy of the measurement;

[0063] 4. Real-time data feedback: Once aligned, the single-point ranging radar 110 in the compass will calculate and display the straight-line distance between the instrument and the tree in real time. At the same time, the electronic compass (attitude sensor 120) measures and displays the instrument's north angle, that is, the angle relative to true north. These data are displayed in real time on the software interface for the operator's reference;

[0064] 5. Data recording: When all required data are clearly displayed on the screen, the operator presses the record button, and the software will automatically record the current tree height and position information, including distance, angle and other parameters;

[0065] 6. Data summary: After completing the measurement of all trees in the entire sample plot, all recorded data can be sorted in the software and exported to Excel for further analysis, statistics and archiving.

[0066] The single-point ranging radar 110 measures the distance by measuring the flight time required for light to be emitted and returned. The distance calculation formula is as follows:

[0067] dis=c×t / 2

[0068] In the formula,

[0069] dis——the distance from the object to be measured to the ranging radar;

[0070] c – the speed of light in the atmosphere;

[0071] t – The flight time required for the radar’s measurement light to travel from launch to return.

[0072] The measurement principle of tree height is as follows:

[0073] 1. Instrument layout: Place the digital forest compass in the center of the plot to ensure that it can cover the measurement of trees in the entire plot;

[0074] 2. Measure each tree one by one: measure each tree in the sample plot in the established order until all trees are measured;

[0075] 3. Aligning the tree roots: When measuring each tree, the operator first uses the virtual crosshairs on the software interface of the compass to align the tree roots. This step displays the distance between the instrument and the tree roots measured by the single-point ranging radar 110 on the screen.

[0076] 4. Record root data: After confirming that everything is correct, press the record button and the software will immediately record the root data of the tree;

[0077] 5. Aim at the tree top: Then, the operator adjusts the virtual crosshairs to the tree top. The software then displays the tree height in real time, which is determined by calculating the two ranging radar data.

[0078] 6. Record the tree top data Press the record button again, the software will record the tree top data and complete the tree height measurement;

[0079] 7. Data collation and export: After all measurements are completed, the data of all trees can be directly exported to Excel tables in the software for further analysis, statistics and archiving.

[0080] In addition, the measurement principle of tree height is based on the following formula:

[0081] First, obtain the distance dis and pitch angle a when the instrument is aimed at the tree bottom, and then obtain the pitch angle b when the instrument is aimed at the tree top. The height H of the standing tree can be calculated using the following formula:

[0082] H=dis×cosa×tanb+dis×sina

[0083] Preferably, the posture sensor 120 includes:

[0084] An acceleration sensor is used to measure the gravitational acceleration components Ax, Ay, and Az of the x, y, and z axes;

[0085] The magnetometer is used to calculate the heading angle N by combining the three-axis gravity acceleration components measured by the acceleration sensor with the pitch angle P and the roll angle R.

[0086] Specifically, the principle of the electronic compass is as follows:

[0087] The tilt attitude of the electronic compass can be detected by a three-axis acceleration sensor. The components of gravity acceleration Ax, Ay, and Az on the three axes are measured, and the pitch angle P and roll angle R can be calculated using formulas (4) and (5).

[0088]

[0089]

[0090] Then the three-axis data XM, YM, and ZM measured by the magnetometer are combined with the pitch angle P and the roll angle R to calculate the heading angle N:

[0091]

[0092] Preferably, the measuring device 100 is also integrated with a single-chip microcomputer, a chip, a USB-HUB module and a storage unit, which together constitute the "brain" of the instrument and are responsible for data processing, management and storage tasks:

[0093] The single chip microcomputer may be an STC15 single chip microcomputer: this is a microprocessor, which serves as a control center processor and is responsible for managing all data processing and communication tasks. It decodes the raw data from the single point ranging radar 110 and the attitude sensor 120, and re-encodes it for transmission through a serial interface;

[0094] The chip may be a CH340 chip: this chip is a USB to serial converter, which converts the UART serial signal processed by the STC15 microcontroller into a USB signal, which facilitates communication with the tablet computer 200 and realizes seamless data transmission;

[0095] USB-HUB module: This module provides multiple USB ports, allowing peripherals such as industrial cameras 130 to be directly connected to the tablet computer 200 through the bus interface. This design facilitates the access of expansion devices and data synchronization processing, and also enhances the scalability of the system;

[0096] Memory unit: The integrated memory unit is used to temporarily or permanently save measurement data, including measurement results and setting parameters. This ensures that data can be temporarily saved even when not connected to a computer and can then be easily uploaded to the tablet 200 for further processing, analysis and long-term storage.

[0097] These integrated electronic components form a highly coordinated hardware system, ensuring that the digital forest compass can quickly and accurately complete the task of measuring the position and height of trees, while uploading the data in real time to the tablet computer 200 for processing, recording and storage, greatly improving the efficiency and accuracy of forest resource surveys.

[0098] In addition, the circuit connection principle is as follows:

[0099] 1. Hardware connection and power supply: The single-point ranging radar 110, attitude sensor 120, STC15 microcontroller and CH340 chip are connected through the UART interface, and the VCC and GND (VCC, i.e. the positive pole of the power supply) ports are used for power supply to ensure that these components are supplied with power. Data is sent and received through TX (transmit port) and RX (receive port);

[0100] 2. Connection between industrial camera 130 and CH340 chip: Industrial camera 130 is connected to CH340 chip through USB-HUB module, and also relies on VCC and ND for power supply to ensure the operation of camera and USB-HUB module. Data communication is realized through UD+ and UD- (positive and negative) ports, corresponding to the bidirectional transmission of USB data;

[0101] 3. Data processing and conversion: The STC15 microcontroller processes data at the hardware level and is responsible for decoding the raw data received from the single-point ranging radar 110 and the attitude sensor 120, and re-encoding it for subsequent transmission. The CH340 chip plays a key role in this process. It converts the signal of the UART serial interface into a USB signal so that the data can be recognized and processed by the PC. The USB-HUB module serves as an intermediate bridge to support the series connection of multiple USB devices, enhancing the system scalability and data transmission flexibility.

[0102] This complex circuit design ensures the smooth transmission of data from various sensors inside the digital forest compass. After being processed by the single-chip microcomputer, the data is converted into a USB signal by the CH40 chip, and finally through the -HUB module, it efficiently interacts with the tablet computer 200, thereby improving the efficiency and reliability of measurement and processing.

[0103] The utility model also provides a digital forest compass measurement system, comprising:

[0104] The measurement hardware is configured as the digital forest compass described above;

[0105] The measurement software consists of embedded software and PC software, among which:

[0106] The embedded software, written in C language under Keil development environment, is responsible for directly interacting with the hardware, extracting data from the single-point ranging radar 110 and the attitude sensor 120, uploading it to the tablet computer 200 through the UART interface after encoding, laying the foundation for data processing;

[0107] The PC software is developed in Visual Studio 20222 using C# language. It is designed as a multi-threaded architecture and is used to provide data processing, visualization and user interaction functions.

[0108] Preferably, the embedded software includes:

[0109] The main thread is used to provide user interface display and control logic. Through this interface, surveyors can observe real-time measurement data and image information, and perform instrument control operations, such as starting measurement and recording data, which greatly simplifies the operation process;

[0110] The serial communication thread is used for data communication with the embedded software. It receives the single-point ranging radar 110 and attitude sensor 120 data uploaded by the embedded software through the UART interface, decodes them, and transmits them to the PC in real time for further processing. This thread ensures seamless connection and real-time performance of the data flow.

[0111] Image processing thread, used to process and analyze image data collected by industrial camera 130. Through algorithm processing, image information is converted into useful data to enhance measurement accuracy and efficiency.

[0112] The combination of these threads enables the digital forest compass to efficiently and accurately complete the investigation of forest resources, reduce human errors, increase data processing speed, and is easy to operate. The collaborative operation of software and hardware reflects the intelligent and integrated trend of modern forestry investigation tools.

[0113] The technical means disclosed in the scheme of the utility model are not limited to the technical means disclosed by the above technical means, but also include technical solutions composed of any combination of the above technical features. The above is a specific implementation method of the utility model. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the utility model, and these improvements and modifications are also regarded as the protection scope of the utility model.

[0114] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back...) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0115] In addition, in the present invention, the descriptions of "first", "second", "one", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0116] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0117] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

Claims

1. A digital forest compass, characterized in that: include: A measuring device, which integrates a single-point ranging radar, a posture sensor and an industrial camera, wherein the single-point ranging radar is used for ranging, the posture sensor is used for determining the position angle, and the industrial camera is used for providing real-time image-assisted description; A tablet computer is connected to the measuring device and is used to process, record and store the data extracted by the measuring device.

2. A digital forest compass according to claim 1, characterized in that: The measuring device comprises a mounting bracket, the tablet computer is mounted on the mounting bracket, and the single-point ranging radar, the attitude sensor and the industrial camera are integrated into the mounting bracket.

3. A digital forest compass according to claim 2, characterized in that: The industrial camera is integrated with an image sensor, and the image sensor and the single-point ranging radar are located on the same surface of the mounting bracket.

4. A digital forest compass according to claim 3, characterized in that: The tablet computer and the single-point ranging radar are respectively located on the front and rear surfaces of the mounting bracket.

5. The digital forest compass according to claim 1, characterized in that: The posture sensor comprises: An acceleration sensor is used to measure the gravitational acceleration components Ax, Ay, and Az of the x, y, and z axes; The magnetometer is used to calculate the heading angle N by combining the three-axis gravity acceleration components measured by the acceleration sensor with the pitch angle P and the roll angle R.

6. The digital forest compass according to claim 1, characterized in that: The measuring device also integrates a single-chip microcomputer, a chip, a USB-HUB module and a storage unit.

7. The digital forest compass according to claim 2, characterized in that: A tripod is provided at the bottom of the mounting bracket.

8. A digital forest compass measurement system, characterized in that: include: The measurement hardware is configured as a digital forest compass as described in any one of claims 1 to 7 above; The measurement software consists of embedded software and PC software, among which: The embedded software is used to extract the data of the single-point ranging radar and the attitude sensor and encode them before uploading them to the tablet computer; The PC software is configured as a multi-threaded structure and is used to provide data processing, visualization and user interaction functions.

9. A digital forest compass measurement system according to claim 8, characterized in that: The embedded software includes: The main thread is used to provide user interface display and control logic; A serial port communication thread, used for data communication with the embedded software; The image processing thread is used to perform image processing and analysis using the image data collected by the industrial camera.

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