基于电子经纬仪及PDA自动量测的电子角规测树原理、功能及精度研究

针对常规角规测树较为粗放的现状,为了满足精准林业的需要,实现单木和林分精准测量,该文以电子经纬仪和掌上电脑为硬件,经PDA编程开发,形成电子角规测树系统,充分发挥了电子经纬仪精密的测角功能和PDA强大的数据处理和存贮功能.利用电子角规可获得树木树干的胸径、树高、任意处直径和材积,树冠部分的表面积和体积,林分的胸高断面积、林分平均高、平均株数、蓄积量和生长量等数据.经过分析,电子角规测树精度为1/7 000,而比特利希角规测树精度总误差达1/32,电子角规的测树精度比普通角规高出200倍以上,其速度也较快.

Principle,practice and accuracy analysis of electronic angle gauge based on electronic theodolite and PDA.

To decrease the error of surveying trees using general angle gauge and to measure individual tree and stand automatically and accurately for the requirement of precise forestry,the authors used the electronic theodolite and palmtop computer as hardwares,developed PDA programs,and finally created an electronic angle gauge.The electronic angle gauge can make full use of the precise angle-surveying of electronic theodolite and the mighty memory of PDA.It can also be used to measure individual tree's diameter at breast height,tree height,diameter of any transect and its height,stem volume,crown volume and its superficial area,basal area,tree number,volume and stand growth,and average height.The precision of electronic angle gauge is(1/7 000) and the total error of Bitterlich angle gauge is 1/32.So the precision of the electronic angle gauge is 200 times as high as general angle gauge and its velocity is higher.