CN105466328A - High precision tree DBH measurer - Google Patents

Abstract

The invention discloses a high precision tree DBH (diameter at breast height) measurer, mainly comprising a fixing clamp, a measuring component and a processing circuit. Two symmetrical L-shaped aluminum sections in the fixing clamp are located on a same plane; a long pawl capacitive grating digital display caliper body and a support bar are fixed to two ends of the aluminum sections; four right angle positioning connecting pieces are installed at the ends of the capacitive grating digital display caliper body and the support bar to form a rectangular support. The center of one of the two L-shaped aluminum sections is grooved to cooperate with a rectangular rope, and is fixed by screws; an elastic fixing rope penetrates the rectangular rope and is fastened to a trunk. A U-shaped support is fixed to the center of the other L-shaped aluminum section; two rubber fixing blocks are fixed to two end faces of the U-shaped support through claw screws; a sensor support is installed at the center of the L-shaped aluminum section and is used for fixing an inductive displacement transducer. The high precision tree DBH measurer has the characteristics of high measuring resolution, and micrometer magnitude precision; meanwhile tree DBH static measurement and dynamic measurement are combined, thereby reducing measuring errors.

Description

High-precision tree diameter measuring device

technical field

The invention belongs to the technical field of test and measurement, and in particular relates to a high-precision tree diameter measuring device.

Background technique

Tree diameter at breast height is the abbreviation of diameter at breast height, and it is one of the most basic factors in the determination of standing trees. The measurement and evaluation of forest volume, biomass and growth are all based on diameter at breast height. The trunk will periodically expand and contract according to the environment or its circadian rhythm, and these physiological activities directly reflect the physiological state of the trunk. Measuring the variation of tree diameter can directly reflect the growth status of plants. Therefore, the measurement of diameter at breast height plays an important role in forest resource monitoring. In addition, precise real-time measurement of tree diameter can provide data support for plant carbon sequestration and growth environment models.

Existing tree diameter measurement devices can be divided into two categories, contact measurement and non-contact measurement. Contact measuring devices generally use sensors as detection components. For example, the Dendrometer plant growth measuring instrument produced by German ECOMATIC Company has a tension sensor, which can monitor the influence of environmental factors on plant water balance and the growth of stem and fruit diameters. Fix the device at the measurement site, and the data can be read directly and recorded automatically, but it can only measure the variation of the tree diameter instead of the absolute diameter and is expensive. Non-contact measuring devices are generally based on photoelectric and electromagnetic technologies, such as the RD1000 laser dendrometer, which has a built-in angular regularity program that can be used to measure cross-sectional area, diameter and tree height, and a built-in inclination sensor for tilt correction measurement. It can accurately collect the diameter of any part of the tree trunk. Although the non-contact measuring device is convenient to carry and measures quickly, the accuracy cannot meet the research requirements and the needs of real-time measurement.

Contents of the invention

In order to overcome the deficiencies of the above-mentioned prior art, the present invention provides a high-precision measuring device for tree diameter at breast height.

The technical scheme adopted in the present invention is:

The invention is mainly composed of a fixing fixture, a measuring component and a processing circuit. The two symmetrical L-shaped aluminum profiles in the above-mentioned fixing fixture are on the same plane, the long-claw capacitive grid digital caliper body and the support rod are respectively fixed at both ends of the aluminum profile, and the four right-angle positioning connectors are respectively installed on the capacitive caliper body with the ends of the support rods, thus forming a rectangular bracket. One of the L-shaped aluminum profiles is slotted at the center to match the rectangular rope buckle, and is fixed by screws, and the elastic fixing rope passes through the rectangular rope buckle and is fastened on the trunk. The U-shaped bracket is fixed at the center of another L-shaped aluminum profile, and the two rubber fixing blocks are respectively fixed on both ends of the U-shaped bracket by horn screws. The sensor bracket is installed at the center of the L-shaped aluminum profile to fix the inductance displacement. sensor. Level bubbles are also fixed on the two L-shaped aluminum profiles, which are used to detect whether the whole device is in a horizontal state.

The above-mentioned measuring components include a capacitive digital caliper and an inductive displacement sensor. The body of the capacitive digital caliper serves as both a support rod and a measuring piece. The capacitive digital caliper is used for static measurement of the diameter at breast height; the inductive displacement sensor is used for dynamic measurement of the diameter at breast height.

Beneficial effects of the present invention:

(1) The instrument is easy to install, light and handy, and has little impact on tree growth;

(2) The measurement resolution is high, and the accuracy reaches the micron level, which meets the needs of measurement and research;

(3) Combining static measurement and dynamic measurement of tree diameter, tree diameter parameters can be directly obtained instead of indirectly obtained, which reduces measurement errors;

(4) The static and dynamic measurement values of tree diameter can be directly displayed and stored, which is convenient for experimenters to process data;

(5) The power supply of the instrument is simple, the power consumption is small, and it is suitable for outdoor long-term measurement.

Description of drawings

Fig. 1 is a schematic diagram of the present invention;

Fig. 2 is a top view of the present invention;

In the figure: 1. Countersunk head screw; 2. Phillips screw; 3. L-shaped aluminum material; 4. Right-angle positioning connector; 5. Support rod; 6. Sensor probe; 7. Level bubble; 9. Nut; 10. Sensor bracket; 11. Inductive displacement sensor; 12. Screw; 13. Horn screw; 14. Rubber fixing block; 15. L-shaped aluminum material; 16. Capacitive digital caliper; 17. Capacitive caliper Ruler body.

Fig. 3 is a side view of the present invention;

Among the figure: 3. L-shaped aluminum material; 9. Nut; 15. L-shaped aluminum material; 17. Capacitive caliper body; 18. Rectangular rope buckle; 19. Elastic fixing rope; 20. Tree trunk.

detailed description

Specific embodiments of the present invention, the present invention will be further described below in conjunction with the accompanying drawings.

As shown in Figure 1, it is a schematic diagram of a tree diameter measuring device. The present invention applies the principle of combining static measurement and dynamic measurement of tree diameter, and uses the measured value of the capacitive digital caliper as the static parameter L of the diameter at breast height, and the measured value of the inductive displacement sensor as the diameter at breast height. Dynamic parameter Δl _i . The composition of the measurement results: the first part is the reading of the capacitive digital caliper, the second part is the reading of the inductive displacement sensor, and the sum of the two is the measurement result, so the real-time measurement value of the tree diameter obtained is L _i =L+2Δl _i .

The measuring device will be described in detail below with reference to FIG. 2 and FIG. 3 .

The L-shaped aluminum material 3 and the L-shaped aluminum material 15 are symmetrically placed on the same plane, and the digital caliper body 17 and the support rod 5 pass through the rectangular grooves of the L-shaped aluminum material 3 and 15 respectively, and are fixed with the Phillips screw 2 to ensure the two supports. The rods are parallel. The four right-angle positioning connectors 4 are respectively installed on the digital caliper body 17 and the end of the support rod 5 to form a rectangular support. One of the L-shaped aluminum profiles 3 centers is grooved to cooperate with the rectangular rope buckle 18, and is fixed by screws, and the elastic fixing rope 19 passes the rectangular rope buckle 18 and is fastened on the trunk. The U-shaped bracket 8 is fixed at the center of another L-shaped aluminum profile 15, and two rubber fixing blocks 14 are respectively fixed on the two ends of the U-shaped bracket 8 by two claw screws 13. After the whole device is fixed on the trunk 20, 2 vials 7 are respectively installed on two L-shaped aluminum materials 3, 15 for detecting whether the whole device is in a horizontal state.

The measuring components include a capacitive digital caliper 16 , an inductive displacement sensor 11 , and a sensor bracket 10 . The capacitive digital caliper body 17 is used as both a support rod and a measuring piece to form a capacitive digital caliper for static measurement of the diameter at breast height; the sensor bracket 10 is installed at the center of the L-shaped aluminum profile 15 for fixing the inductive displacement sensor 11, and the device The sensor measuring head 6 is redesigned. The measuring head is rectangular. After assembly, the position of the inductive displacement sensor 11 is adjusted to make the measuring head contact with the tree trunk to ensure that the measuring head is tangent to the tree trunk, so that the data measured by the measuring head is the diameter of the tree. At this point, the clamping of the inductive displacement sensor is completed. The inductive displacement sensor 11 is connected with the signal processing and transmission circuit. The signal processing and transmission circuit can receive the sensor signal and process it. The processed data is uploaded to the upper computer through the wireless transceiver and data transmission module. The signal processing and transmission circuit is provided with a timing wake-up program. The data can be collected at fixed time intervals and uploaded to the host computer for display. The host computer receives and processes the data remotely, and the host computer receives and stores the data and draws the corresponding table to obtain the change of the trunk within the required time period.

The specific operation process of the present invention is: after the L-shaped aluminum profile 3, the digital caliper body 17, and the support rod 5 are installed firmly, one of the L-shaped aluminum profiles 3 is matched with the rectangular cord buckle 18, and the elastic fixing rope 19 passes through the rectangular cord. The rope buckle 18 is fastened on the trunk 20; then the L-shaped aluminum material 15 is fixed on the digital caliper body 17 and the support rod 5, the U-shaped bracket 8 is fixed by the screw rod 12 and the nut 9, and the sensor bracket 10 is installed with the L-shaped The center of the aluminum material 15 is used to fix the inductive displacement sensor 11. Tighten the horn screw 13 so that the two rubber fixing blocks 14 touch the tree trunk and play a role in stabilizing the whole device; install the two level bubbles 7 on the two L-shaped On aluminum materials 3 and 15, check whether the entire device is in a horizontal state, and adjust the balance of the device until the measurement requirements are met. At this time, the capacitive digital caliper 16 can be used to measure the static parameters of the tree diameter, and the number of records displayed is L. In the circuit part, the inductive displacement sensor 11 measures and stores the tree diameter dynamic parameter measurement every 30 minutes, and records the dynamic indication value Δl _i , so the real-time value of the DBH measurement is: L _i =L+2Δl _i .

The invention can complete the measurement of the diameter and circumference of the plant trunk in real time, has a large measurement range, and reduces measurement errors and workload. The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (1)

1. high precision tree breast-height diameter device, is characterized in that: this device is formed primarily of stationary fixture, measurement component, treatment circuit; In above-mentioned stationary fixture, two symmetrical L-type aluminium section bars are in the same plane, long pawl permitting condition blade and support bar are separately fixed at aluminium section bar two ends, four right angle positioning links are installed on respectively and hold grid slide calliper rule blade and support bar end, thus form rectangle support; Wherein a L-type aluminium section bar center fluting coordinates with rectangle sling, and is fixed by screw, and flexible fastening rope is anchored on trunk through rectangle sling; U-shaped support is fixed on another root L-type aluminium section bar center, and two rubber fixed blocks are fixed on U-shaped support both ends of the surface by goat's horn screw respectively, and sensor stand is installed on this root L-type aluminium section bar center, for fixed inductance displacement transducer; Two L-type aluminium section bars being also fixed with air level, whether being in horizontality for detecting whole device;

Above-mentioned measurement component comprises permitting condition, inductance displacement sensor; Permitting condition blade both as support bar also as measuring piece, permitting condition be used for diameter of a cross-section of a tree trunk 1.3 meters above the ground static measurement; Inductance displacement sensor is used for diameter of a cross-section of a tree trunk 1.3 meters above the ground kinetic measurement.