Dong Guangyan, BS, Senior EngineerDong Guangyan, BS, Senior Engineer2010-092010-09

OutlineOutline 1.1. SummarySummary

2.2. Basic principle & typical Basic principle & typical

specificationsspecifications

3.3. Comparison with traditional Comparison with traditional

surveying technologiessurveying technologies

4.4. Application statusApplication status

5.5. Advantages & disadvantagesAdvantages & disadvantages

6.6. ExpectationsExpectations

1.1. SummarySummary

A fire-new technical approach Single point manually collecting data continuously & automatically

acquire batch data Two types---airborne and ground

(according to difference of platforms)

satellite borne

2. Basic principle and 2. Basic principle and specifications of typical specifications of typical instrumentinstrument

Target Interface Post-processing

Signal processing

Transmitter

Receiver

Figure 1 Principle sketch map of 3D laser surveying system

The hardcore is a 3D laser scanner ， which mainly consists of the laser transmitter, receiver, scanning system and bracket system ， meanwhile, it integrates with CCD digital camera and internal calibration systems as well.

Non-contact, high speed laser measurement

mode

Acquiring 3D data of terrain and array geometry

of surface of complicated object with point cloud.

TOF (Time of Flight) pulse ranging method

Approach to calculation of 3D laser spot

coordinate for pulse ranging method

Basic principleBasic principle

Calculation expressions：

sin

sincos

coscos

SZ

SY

SX

s

s

s

S

α

Z

Y

P(Xs,Ys,Zs)

θ X

Figure 2 Spatial coordinate system of 3D laser surveying system

Basic principleBasic principle

Typical instrument

Optech ILRIS-36D

Capture Every Dimension

Typical instrument

Leica HDS3000

Typical instrument

Mensi GX RD 200+

Main specifications of typical instrument

Manufacturer Optech Leica Mensi

Products ILRIS-36D

HDS3000 GX RD200+

Laser Security Class 1 1500nm Class 3 Class 3 532nm

Ranging accuracy 7mm@100m Single point 4mm@50m Single point 7mm@100m

Positioning accuracy 8mm@100m 6mm@50m Single point 12mm@100m

Range (min.) 1.5m 1m 1m

Range( max.) 1500,1000,80080% 40% 20%2600m for DR

300m@90%134m@18%

200m-90%350m

Scan angle of view 110°V×360°H 270°V×360°H 60°V×360°H

Built-in digital camera

6 million pixels 1 million pixels24°×24° 111 pictures

Integrative color camera5.5 × optical zooming

Postprocessing software Polyworks/Inspector Cyclone Realworks

Modeling precision 3mm 2mm 2mm

3. Comparison with traditional surveying technologies

Different requirements for measurement

accuracy and ambients

Different raw data patching format

Different data combined modes among the

sites

Different build modes for TIN models

Different extract modes for grains

4. Application status 3D laser scanning system can rapidly rebuild a

3D solid model of an object. 3D laser point cloud data can also use the

complete target data for post processing(such as ： mapping, computation, stress analysis, finite element analysis, simulation analysis, mission analysis, ⋯etc.)

It is a symmetric application of all kinds of forward engineering tools (e.g. ： CATIA, UG, CAD, PDMS, PDS, GIS, VR, 3DSMAX, MAYA, ERP, etc.)

4. Application status

Generate data image by surveying a target’s 3D coordinate ， then process the data to extract 3D information and generate ：

a ） Digital elevation model DEM with high accuracy, contour map and orthograph ；

b ） 3D solid image of buildings ；c ） Urban 3D diorama ；d ） Height of trees, vegetation

4. Application status

Figure 3 Image of 3D laser surveying system

4. Application status

Figure 4 Buildings extracted from Figure 3

4. Application status

Fields covered ： cultural relic, archaeology, architectonics, spaceflight, aviation, shipping, manufacture, military industries, military, petrifaction, medicine, water conservancy, energy sources, electric power, traffic, machinery, movies & TV, education, scientific research, automobile, public security, city construction⋯⋯

Application

Historical Preservation

Application

Historical Preservation

Application

Urban Planning

Application

Urban Planning

Application

Industrial Survey

5. Advantages & disadvantages Advantages ：High speed ， complete measurement, accurate ， multi-

angle-of-view observation ；Non-contact measurement ， all-weather ；Shape measurement for completed surfaced object ， color

revivification ；Mark and measure relative model data, such as range,

altitude difference, volume, surface area, section, 2D picture etc.

Build all kinds of geometry shape ， such as elbow, taper tube etc.

Convert 3D model into data format of CAD system or different software operating platforms for 3D modeling.

Advantages example

With point cloud of intensity information ， it will support output to CAD environment for editing and analysis.

Advantages example

The point cloud figure with RGB information can revert the environmental information. �

Disadvantages and challenges ：3D laser scanner is a black box system ， it

is hard to calibrate ；Current instrument are still not perfect in

miniaturization and price ， and they are top grade equipment in market ；

Longer processing time after data scan ；The scan data patch soft wares are not

perfect (lack of compatibility) 。

5. Advantages & disadvantages

Disadvantages and challengesLack of consideration of

standardization ， Lack of soft wares both practical and lower price ；

It is hard to use the fruits of 3D modeling for further speciality research ；

3D modeling has certain subjectivity ， and the laypeople usually visually are puzzled by virtual cartoon ， surveyablity and science of 3D model is ignored.

5. Advantages & disadvantages

6. Expectations

Future works ：

● Unification of term

● Establish data standard for accuracy requirement

● Data collection and post-processing requirements

● Approach to fruit accuracy assessment

3D laser scanning technique has

unexampled advantages in 3D data

rapid acquirement and build 3D model.

It is prospective with further effort.

Thanks!