Kombinasi data laser scanning dan fotogrametri digital untuk pemodelan 3D Candi Borobudur

ANDARU, Ruli, Harintaka, ST.,M.T

2010 | Tesis | S2 Teknik Geomatika

Pembuatan model 3D sangat diperlukan dalam bidang arkeologi guna perekaman, dokumentasi dan keperluan rekonstruksi dalam kerangka perlindungan dan pemeliharaan benda cagar budaya. Pembuatan model 3D bisa dilakukan dengan 3 metode yaitu image based modelling, range based modelling dan combination of image and range based modelling. Balai Konservasi dan Peninggalan Borobudur (BKPB) telah menerapkan metode image based modelling dan range based modelling dalam melakukan perekaman obyek candi. Metode image based modelling memiliki keterbatasan pada tingkat kedetilan obyek, sedangkan range based modelling memiliki keterbatasan pada aspek radiometrik. Metode combination of image and range based modelling dikembangkan untuk mengatasi permasalahan tersebut. Pada penelitian ini dilakukan kajian terhadap ketiga metode tersebut. Kajian difokuskan pada segi biaya, kualitas data, kualitas geometri, teknis pemodelan, efektifitas dan efisiensi pengambilan dan pengolahan data dalam pemodelan objek 3D. Pengukuran dilakukan dengan cara scanning menggunakan Terrestrial Laser Scanner Optech ILRIS 3D secara multi station dengan 8 titik stasiun perekaman. Adapun pemotretan dilakukan menggunakan Canon EOS 1000D dan diproses secara fotogrametri. Uji akurasi posisi model 3D candi dilakukan menggunakan 46 titik cek yang diukur posisinya secara teliti menggunakan Reflectorless Total Station. Adapun uji geometri hasil pemodelan dilakukan secara empirik dengan membandingkan hasil pengukuran geometri obyek candi pada model dibandingkan dengan hasil pengukuran langsung pada obyek candi. Hasil penelitian menunjukkan bahwa model 3D metode combination of image and range based modelling memiliki tingkat akurasi tinggi dan secara signifikan meningkatkan aspek radiometrik. Berdasarkan hasil uji ketelitian posisi dengan data ukuran Reflectorless Total Station sebagai data referensi diperoleh RMS untuk arah x, y dan z kurang dari 2 cm, sedangkan uji ketelitian jarak diperoleh RMS kurang dari 2,5 cm. Tidak ada perbedaan geometrik secara signifikan akibat proses kombinasi, dan dari kajian terhadap dua metode lainnya, metode combination of image and range based modelling memberikan hasil visual yang lebih baik serta efisien dalam melakukan pendataan digital 3D candi Borobudur. Hasil penelitian ini menunjukkan bahwa metode combination of image and range based modelling dalam hal menampilkan keaslian bentuk, kedetilan obyek dan tekstur/warna lebih baik dibandingkan dengan kedua metode sebelumnya, oleh karena itu untuk membantu tugas pokok dan fungsi BKPB dalam kerangka pengelolaan dan perawatan candi metode ini sebaiknya diterapkan.

3D modeling is very needed in the field of archeology to recording, documentation and reconstruction within the framework of the protection and maintenance of cultural heritage building. 3D modeling can be done by three methods, image-based modeling, range-based modeling and the combination of image and range-based modeling. The object of this research is Borobudur Temple, located in Magelang regency, Central Java. Borobudur Conservation Agency (BKPB) has applying image-based modeling method and range-based modeling in the digital documentation, but image-based modeling methods have low levels of object detail, while range-based modeling have low radiometric aspects. Combination of method and range image based modeling was developed to overcome these problems. In this research, a 3D model will be compare in terms of cost, data quality, comparison geometry, technical modeling, the effectiveness and efficiency of retrieval and processing of data in the modeling of 3D objects. Measurement is conducted by scanning using Optech 3D ILRIS Terrestrial Laser Scanner in multi station with 8 points of recording station. While the photography was carried out using the Canon EOS 1000D and processed with photogrammetric solution. Evaluation of the position accuracy was carried out using 46 check point with measured using Reflectorless Total Station and direct measurement using tape meter. The results shows that the combination of image and range based modelling has a high accuracy and significantly improve radiometric aspects of the 3D model. Evaluation geometric accuracy is represent by the RMS error for the direction of x, y, z and distance. Based on the 3D model results, it is find that RMS error (x,y,z) is less than 2 cm and for distance accuracy obtained that RMS error is less than 2,5 cm. There are no significant geometric differences due to the combination process, and for the comparison with two other methods, the method of combination of image and range-based modeling is the best and efficient method for 3D documentation of Borobudur temple. This is accordance with BKPB duties within the framework of the management and maintenance aspects of the temple, where object details and texture/color becomes an important element while making the digital documentation of the temple.

Kata Kunci : Laser scanning,Fotogrametri digital,Model 3D