Large Scale Topographic Mapping in Indonesia

Dr. Ade K. MulyanaAldino Rizaldy

Edwin Hendrayana

Center for Topographic Mapping and ToponymsGeospatial Information Agency

Indonesia

Background

• Law No.4/2011 on Geospatial Information mandates a.o.:– Transformation from BAKOSURTANAL (National

Coordinating Agency for Surveys and Mapping) into BIG (Geospatial Information Agency)

– BIG to provide topographic maps as base maps for all thematic maps at small, medium dan large scales

– Large scale mapping: 1:10,000 1:5,000 1:2,500 and 1:1,000

• Land area of Indonesia: 1.9 million km2

• Prioritization: large scale mapping only for the urban area• At 1:5.000, # sheets for city area (non-district) is more than 15,000.

– Capital of provinces– Other cities in need of Detailed Spatial Planning

No. Scale Total # Sheets

# Sheets available

# Sheets to do

1 1:10.00091,547 780 90767

2 1:5.000283,866 0 283866

3 1:2500880,206 0 880206

4 1:10002,729,319 0 2729319

Large Scale Topographic Mapping Projects

Loan from JICA (Japan) 2011-2014:•4 cities at 1:10,000 (123 sheets ~2600 km2)• Performed by a Japanese company•Part of NSDI project (1:50K and 1:10K)

National Budget, 2012:•6 cities at 1:10,000 (131 sheets)•Performed by 2 Indonesian companies

National Budget, 2013:•4 cities at 1:10,000 (131 sheets)•1 city at 1:5,000 (98 sheets)•Performed by 3 Indonesian companies

20121:10.000

Makassar

Pare Pare

Manado, Tomohon, Bitung

Gorontalo

1:10.000 Digital Photogrammetry

Project Specification• Ground Control Point (GCP):

– 20 cm planimetric accuracy and 15 cm vertical accuracy– GCP must be signalized– GCP distribution: in the center and in the corner of the block, as well as

along the perimeter.– Independent Check Point (ICP) must be distributed for each map sheet.

• Photos:– Ground Sampling Distance (GSD) 20 cm– Overlap/sidelap 60%/30% for flat area, and 70%/40% for mountainous area– Camera must be equipped with GNSS/IMU

• Flight plan: Crossflight is mandatory• Aerial Triangulation (AT):

– sigma naught of 10 micron and GCP Planimetric RMSE 1 m; Vertical RMSE 0.5 m

• Topographic map compilation:– Stereoplotting is conducted to produce masspoint, spotheght and breakline– DEM building from masspoint, spotheight and breakline– Contour will be generated from DEM– Feature collection threshold is 5 m

1:10.000 LIDARProject Specification

• Density of point cloud is ≥ 4 points/m2

• Three return per pulse must be recorded include first return and last return

• ≤ 20 cm of vertical RMSE LIDAR• GSD 12 cm for orthoimage• LIDAR system must be included with GNSS/IMU• Filtering or classification must be performed to

post-processing LIDAR raw data to create Digital Surface Model (DSM) and Digital Terrain Model (DTM)

20131:5.000

1:5.000Project Specification

• Ground Control Point (GCP):– 20 cm planimetric accuracy and 15 cm vertical accuracy– GCP must be signalized– GCP distribution: in the center and in the corner of the block, as well as along the

perimeter.– Independent Check Point (ICP) must be distributed for each map sheet.

• Photos:– Ground Sampling Distance (GSD) 15 cm– Overlap/sidelap 60%/30% for flat area, and 70%/40% for mountainous area– Camera must be equipped with GNSS/IMU

• Flight plan: Crossflight is mandatory• Aerial Triangulation (AT):

– sigma naught of 10 micron and GCP Planimetric RMSE 0.5 m; Vertical RMSE 0.3 m• Topographic map compilation:

– Stereoplotting is conducted to produce masspoint, spotheght and breakline– DTM building from masspoint, spotheight and breakline– Contour will be generated from DTM– Feature collection threshold is2.5 m

GCP Measurement

GCP Measurement

Signalized GCP / ICP

Flight Result(Camera Exposure)

CROSS LINE

CROSS LINE

Image Result(Makassar, GSD 12 cm)

Orthomosaic Image Result(Manado, GSD 12 cm)

DSM Result(Manado, 16 cm resolution)

Accuracy Test (Manado)12 cm GSD

LIDAR + Medium Format CameraLeica ALS70 + RCD30

32 ICP’s

RMSEx = 0.263 mRMSEy = 0.320 mRMSEz = 0.654 m

Horizontal Accuracy0.717 m

Vertical Accuracy1.283 m

Accuracy Test (Pare Pare)12 cm GSD

Medium Format CameraLeica RCD30

15 ICP’s

RMSEx = 0.079 mRMSEy = 0.090 mRMSEz = 0.412 m

Horizontal Accuracy0.207 m

Vertical Accuracy0.808 m

Accuracy Test (Medan)25 cm GSD

Large Format CameraVexcel Ultracam-X

18 ICP’s

RMSEx = 0.234 mRMSEy = 0.267 mRMSEz = 0.483 m

Horizontal Accuracy0.614 m

Vertical Accuracy0.947 m

Digital Elevation Models of Makassar

Source: Digital Aerial Photographs, June 2012Processing Method: Digital PhotogrammetryPurpose: Topographic Mapping at 1:10,000

Topographic Mapping Process

Challenges

• Human resources• Standards and Project Specification• Data Acquisition– Camera and LIDAR equipment

availability– Aircraft availability:

• Weather (rain and cloud) and terrain condition