Design Of Needle Measurement System For Tree Annual Ring

The tree annual rings reflect the growth of trees.In spring and summer,when the rainfall is large and the illumination time is long,the trees grow more and form early wood.In autumn and winter,because of low temperature and lack of precipitation,trees grow less and form late timber.Based on the research of tree annual rings,we can extract the climate change situation and laws of the growth environment of trees.Traditional tree annual ring research methods need to obtain a tree disk or use a growth cone to drill a wood core,which is extremely harmful to the trees,and the research efficiency is relatively low.The demand for efficient and accurate information of tree rings is increasing in tree annual ring research.The needle measurement system for tree annual ring designed in this paper can realize measurement of tree annual ring with accurate,efficient and small invasive,which is of great significance for improving the efficiency of tree annual ring research and realizing small invasive measurement of tree annual ring.This paper introduces the design and implementation process of needle measurement system for tree annual ring in various parts from the aspects of mechanical structure design,control system design,data processing algorithm design and test experiments.In this paper,the selection of the overall mechanical design scheme of the needle measurement system for tree annual ring is firstly carried out,the linkage type and the discrete type are compared,and the discrete type overall mechanical design scheme is selected.The design of micro drill needle,support plate and copper sleeve of the needle measurement system for tree annual ring are completed,and the specific functions of each part are explained.In the design of measurement and control system,the principle of tree annual ring measurement is expounded,the main control chip TMS320F2812 minimum function system design,power supply system design,selection and control of rotating motor and propulsion motor,signal amplification circuit design and double closed loop control algorithm design of DC servo brush motor are completed.In the design part of tree annual ring measurement data processing algorithm,the data processing algorithm is selected according to the characteristics of the data.The processing effects of Butterworth data processing algorithm,Chebyshev data processing algorithm and ellipse data processing algorithm on the original tree annual ring measurement data are compared.Ellipse data processing algorithm is selected as the data processing algorithm of this system.In the part of the test experiment,this paper selects four kinds of tree disks with known annual ring numbers,namely larch,spruce,fir and red birch,to carry out the tree annual ring measurement experiment.The accuracy of tree annual ring measurement is above 90%,and for larch and fir with obvious tree annual ring characteristics,the accuracy of tree annual ring measurement is above 95%.The needle measurement system for tree annual ring has also been used to measure the tree annual rings of Pinus tabulaeformis and Sabina chinensis.The measured results of the living trees are basically consistent with the tree information recorded in the data.The experimental results show that the needle measurement system for tree annual ring can realize measurement of tree annual ring with accurate,efficient and slightly damaged,the needle measurement system for tree annual ring can provide a large number of effective tree annual ring data for research and realize the age discrimination of ancient and famous trees on the premise of slightly damaged,it can also provide a basis for the analysis of internal decay of trees.