DynaRoot Dynamic Root Evaluation System
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DynaRoot Dynamic Root Evaluation System U SER ’ S M ANUAL

2 THE PULLING TEST CONTENTS 3 The DynaRoot dynamic root evaluation system 2 4 How does DynaRoot work? 3 A Transferring data wirelessly on Windows 35 1 Introduction The stability of urban trees is a key question that affects everyone. Diseased and unstable urban trees pose much risk for everyone, and are a serious liability for municipalities in case of an accident. Tree stability assessment is therefore of the utmost importance. In the meantime it tends to be much neglected in many areas. At present, there is only one accepted method for tree stability assessment. The pulling...

THE DYNAROOT DYNAMIC ROOT EVALUATION SYSTEM Figure 1: Schematic of the pulling test. The DynaRoot dynamic root evaluation system It would be much simpler to use the loads that arise from the actual wind rather than a loaded cable, to assess the tree’s safety in a high wind situation. There are, however, two interrelated problems that makes this very complicated: 1. Trees consist of a complicated network of trunk, major, minor branches, twigs and (in the summer) leafs. This situation is not unlike a multiple pendulum that reacts to loading in a very unpredictable, erratic manner, when the...

HOW DOES DYNAROOT WORK? Figure 2: Two-dimensional time series plot of inclination and wind velocity. One way to evaluate such systems is using statistical parameters of the data taken over longer intervals. There is no immediate relationship between the wind velocity and the inclination at any given moment, but there is a relationship between their averages and other statistical parameters observed over a longer interval. The DynaRoot system takes advantage of this statistical relationship. How does DynaRoot work? The DynaRoot system consists of three components (see Figure 3): 1....

HOW DOES DYNAROOT WORK? Figure 3: Components of the DynaRoot system Figure 4: Relationship between the wind pressure and the inclination

SOME CONSIDERATIONS CONCERNING THE MEASUREMENT Figure 5: An important condition for DynaRoot to be applicable is a sufficiently large wind speed. Some considerations concerning the measurement The distance between the measured tree and the anemometer The intensity of the wind gusts may be different from location to location, even within a relatively small area. The relationship between wind intensity and inclination is obviously closer if wind velocity is measured close to the tree. Nevertheless, fairly accurate correlations can be achieved if the anemometer is located within 1.5 km (1 mile)...

SOME CONSIDERATIONS CONCERNING THE MEASUREMENT Figure 6: Relationship between averaging time and the resulting correlation coefficient measurement than the pulling test. It is also easier to set up and carry out; no need for heavy equipment, ladders and physical exertion during the test. There are only two disadvantages to this measurement. One is that sufficiently high wind velocities (at least 25 km/h or 15 mph) are required, which may be a problem when urgent results are expected. The other issue is that the measurement is more time consuming than the traditional pulling test. However, it...

6.2 Dual axis inclinometer • Measurement range ±2 degrees • Resolution: 0.001 degree • Temperature compensated • Sampling rate: 10 Hz • Integrated GPS • Data storage capacity: 8 GB (SD card) • Mounted by a single screw • Operating voltage and current: 12V, 20 mA • Completely weather proof, IP65

7 OPERATION GUIDE 6.3 DynaRoot software 7 OPERATION GUIDE 6.3 DynaRoot software OK GPS SD CARD INCL.. M ELASTOM LOBAT WIFI CONN Figure 7: Indicator lights on the LED display panel in the case of an inclinometer. • Simple yet efficient software for determining the safety factor • Automatic merging of wind velocity and inclination data • Diagram, critical wind pressure, correlation coefficient and safety factor calculation • Runs under MS Windows. 7 Operation guide DynaRoot system should be used on days with at least 25 km/h (15 mph) wind gust velocities. Setting up the measurement involves...

OPERATION GUIDE WIFI START Inclinometer setup Figure 8: Buttons of the control panel . • wait for the OK LED to light up. This may take a few minutes depending on the quality of GPS signal reception. • when the OK LED is lit, you may press SD START on the control panel located on the side of the instrument box (see figure 8). Use the provided magnetic stick to operate the buttons. Once pressed, the OK led starts blinking. You may now optionally disconnect the LDP. • record data for a suitably long period of time (the longer the better. The minimum is 1 hr, but 3 hrs are recommended.) • hit...

OPERATION GUIDE Anemometer setup Anemometer setup Assemble the anemometer tower, attach the anemometer on the top, and erect the tower. Wind velocity readings are sent to, and data is collected at the instrument box located at the bottom of the tower. Starting and stopping the data collection, recording and transferring data happens much the same way as described above at the inclinometer. The instrument box contains the same control panel (including start and stop buttons) as that of the inclinometer. Do not forget to press “Tara” button inside the instrument box before raising the...

OPERATION GUIDE Transferring data from the SD card to a different device instrument instance. The connection uses the WPA security protocol for authentication, for which the passphrase is Ddar-123. In the following we are going to illustrate this process under Android OS. The steps needs to be taken are very similar on other platforms (see appendix A for an overview of how to do it on Windows 10). Figure 9: Go to Settings / Wi-Fi to see the available Wi-Fi networks. Select the network with SSID DDARXX:XX:XX:XX:XX:XX, where the part after the hyphen is a unique MAC address. In the concrete...

OPERATION GUIDE Transferring data from the SD card to a different device Figure 10: Enter the passphrase Ddar-123.