Light Detection and Ranging - FECA© 2013 Infotech Enterprises LiDAR stands for Light Detection and...

© 2013 Infotech Enterprises. All Rights Reserved

We deliver Global Engineering Solutions. Efficiently. June 7, 2013

Light Detection and Ranging

Rajnish Chauhan

© 2013 Infotech Enterprises

LiDAR stands for Light Detection and Ranging. Initial laser vector is

transformed through a series of reference systems to yield object coordinates

in a chosen Coordinate System

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LiDAR

Types of

LiDAR

Terrestrial

Mobile

Airborne


Due to its fast data capture and processing, its applications are in various

areas. Some of them are

1. Utilities (Gas, Electric, Water, Sewer etc.,)

2. Floods

3. Coastal Applications

4. Forest Mapping

5. Urban Applications,

6. Cellular Network Planning

7. Mining

8. Corridor Mapping (Rails and Roads)

9. Glacier and Avalanche

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LiDAR - Applications


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LiDAR Benefits

Delivers high accuracy products with effective cost

Quick data collection and processing

Acquisition in all seasons – Leaf on and Leaf off

Enables mapping of larger project area

Provides robust data sets with multiple possible

products

Performs better in vegetated areas than

photogrammetry


Best LiDAR inputs based on the activity

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LiDAR for Electric Utilities

Airborne Terrestrial Mobile

Substation Transmission Distribution


Transmission

o LiDAR data helps to simulate the exact scenarios for various purposes by using design

software like PLS-CADD

o LiDAR technology provides accurate elevation models for transmission lines

o LiDAR helps to locate grow-in and fall-in trees for TVMPs to keep utilities in NERC FAC-003

compliance

Substation

o DEM generated by LiDAR point cloud helps in finding the best location for substation

o Terrestrial LiDAR is used to capture all significant information of the substation safely by

reducing potential hazards of having a surveyor at the data point.

Distribution

o Spatial location of poles, transformers, street lights and switch gears can be extracted

o Height and associated feature information can also be extracted for poles & towers

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Value addition for Electric Utilities

© 2013 Infotech Enterprises 7

Utilities Business Need

Reliability

Avoid trees contacting the transmission lines

Public Safety

Avoid energized transmission lines from sagging

Forest Fires

Prevent tree related fires

FAC-008 FAC-003 FAC-003


Utilities Business Drivers

USA

NERC prompts encourages transmission owners to review their VM activities under Reliability Standard FAC-003 and FAC-008.

UK

ESQCR prompts encourages transmission owners to avoid tree-related outages and to review their VM and compliance activities amended under ESQC(A)R 2006.

Australia

Electricity Safety (Bushfire Mitigation) Regulations 2003 and Electricity Safety (Electric Line Clearance) Regulations 2010 are formed to control forest fires and outages

Stringent Regulatory Compliances


LiDAR Classification

Classification helps in turning off the points related to unnecessary classes to facilitate

easy vectorization and to analyze clearances, accesses, obstacles and hazardous

vegetation encroachment etc.

Ground

Vegetation

Pole


LiDAR Classification – Huge Data, More Manageable

Difficult to distinguish the features

Easy identification of features


LiDAR Classification - Clarity

Before Classification

After Classification

Everything looks same in the

unclassified LiDAR and unable to

identify the poles and catenaries in

order to vectorize the data

© 2013 Infotech Enterprises. All Rights Reserved

We deliver Global Engineering Solutions. Efficiently. June 7, 2013

Infotech’s LiDAR Capabilities


• Generate and update large data of landbase information for

various counties across the globe through combination of

Photogrammetric and LiDAR technologies

• Used LiDAR for producing highly accurate Digital Elevation

Models ranging from 0.05 meters to 0.5 meter resolutions

• Executed several projects for government clients, e.g. York

County and City of Los Angeles

• Comparative advantage of capturing LiDAR DEM over

conventional photogrammetric collection i.e. 10,000 points /

sec against 1,500 points / hour

Overview


Services offered

• Post-processing

• Bare Earth Classification

• Feature Classification

• Elevation Modeling


Process Flow

Post- Processing

Data Models

Classification

Filter

Processing

Last Return

Processing

Digital Surface Models

Vegetation & Canopy

Classification

Building Classification

Utility Classification

Digital Terrain Models

Hydro Models

Transportation

Volumetric

Primary

Classification

Trajectory

Correction

Projection

Parameters

Surface Model

Bare Earth

Model

First Return

Processing

Ra

w L

iDA

R


Acceptable inputs for processing

• Time stamped trajectory information

• LiDAR point cloud

• Ground Control Points

• Project boundary - AOI

• Point density slicing

• Accuracy

• Other sources – Orthoimagery etc

• Standards or guide lines to follow


Software Used In Processing Phases

• LiDAR post-processing

o Terra Modeler T-Match

• LiDAR classification

o Terra Modeler

o Terra Scan

o Microstation

• LiDAR management

o Geo-QUE

• FME

o Data Conversions

o Quick hill shade view

o Quality checks and validation.

o New template


• Analyze Mismatch in Laser inputs o Pre-Processing of inputs and analysis of mismatches in

Flights lines, Trajectory, Laser points etc.

• Apply Corrections to Data Sets: o Correction in accuracy of trajectory elevations such as

fixing of systematic errors in position, orientation

o Correction of heading, d-Easting, d-Northing, roll and pitch

for whole data set

o Correction of heading, d-Easting, d-Northing roll and pitch

for each flight line

o Modify laser points of each interval with a unique Z

correction

• Matching Data sets o Matching of crossing flight lines

o Linking of laser points to trajectory position

o Matching of flight line number to trajectory number

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Capability illustration | Post Processing


Capability illustration | Bare Earth Classification

Raw Data Edited Data

The bare earth DEM includes all significant visible constructed features if they appear to sit on the earth or

at ground level, e.g. roads built on embankments (including over pipe culverts). Small structures and all

structures built above the ground are removed, e.g. bridges, solid concrete road dividers.


Bare Earth Classification

• LiDAR post-processing steps yield a cloud of first and last return mass

points

• Classifying last return points which do not represent the terrain yields

Bare Earth Models

• Classifying first return points representing above ground features

(including some ground contact ) yields Surface Models

• Bare Earth Models classified as Bare Earth DEMs

• Surface models classified as Digital Surface Models (DSM)

• Entire ground points can be classified by ground class routines and

algorithms run with Terra Scan

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Raw LiDAR

Bare Earth

Capability illustration | Example


Vegetation Classification

• Filtered from first return laser points with

classified ground points

• Automatic vegetation / canopy classification

using macro algorithms

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Hydro Classification

• Hydro features – rivers, streams, lakes, ponds etc.

classifed by auto algorithms and routines run in

Terra Scan

• Laser points inside the captured hydro features are

classifed to Water Class

• Assign constant elevations to classifed polygon

hydro features

• Placement of Breaklines to delineate the continuity

of the rivers/streams beneath bridges/culverts.

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Classified Hydro

Delineated Hydro



Building Classification

• Filtered from first return laser points with classified

ground points

• Automatic building classification using macro

algorithms. Show the extensibility to non-flat roofs

with the help of few manual interactions.

• Routines applied to classify buildings by specifying

the following inputs:

• Minimum size of the building

• Steepest Roof angle

• Maximum empty gap between points belong to

same roof

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Surface Data with Building

Classified Buildings


Utility / Transmission Classification

Power Transmission line and corridor mapping:

Laser points are classified to power lines by semi-

auto routines.

Manually extract tower strings.

Wire lines are detected automatically by using

tower strings. Manually classify the pylons, arms

and attachments.

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Generate the bare earth LiDAR terrain models ranging

from 0.5 meter to 5 meters. The vertical accuracy of

these terrain models are highly precise compared to

conventional aerial photographic DEM

Generate LiDAR DEM by classifying bare earth data

of first return lidar cloud points and the DSM is

generated by extracting the last return of cloud points

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DSM

Capability illustration | Elevation Modeling


Terrain Modeling

• Bare Earth DEMs are generated by classifying bare earth data of last

return cloud points

• Generate Bare Earth DEMs ranging from 0.075 meters to 0.5 meter

resolutions with suitable grid intervals.

• Generate DEM’s suitable to generate contours of cartographic

standards supplemented with breaklines using aerial, satellite imageries

or lidargrammetry (no associated image).

• Generate DSM by filtering point cloud of first returns.

• Produce DSM products of post spacing ranging from 1m to 5m

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Contour

DSM

DEM



Capability illustration | Volumetric Analysis

Identification & delineation of ore dumps Creation of DEM Volume calculation of dump piles Dump Analysis

• Identification of the dump piles

• Area calculation of piles

• Volume calculation of piles

• Change detection of pile health


Achievable Accuracies :

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Accuracies and Post Spacing Achieved

Scale Point

Spacing

Equivalent

contour interval

Vertical

Accuracy

Horizontal

Accuracy in cm

1”=100 I m 1 ft 10 cm 68

1”=200

2 m 2 ft 20 cm 1.3 m

1”=400

3-4 m 4 ft 40 cm 2.7 m

1”=500 5 m 5 ft 50 cm 3.3 m


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Processing Capacity

Ability to scale up/down resources on demand

Process Capacity /month

Post-Processing <=1000 Sq.km

Bare Earth and elevation Models ~ 1000 Sq.km

All Feature classification ~ 500 Sq.km


Infotech Edge

Standard Operating Procedures

Knowledge management

Quality Management systems

Global ERP

Process

People

Recruit, deploy and retain best talent

Technology, Tools & Training

Robust, Flexible, Modular Global Infrastructure

• Multi Million hours of experience, strong technical and domain expertise

• Robust and scalable global delivery model and project execution framework

• Predictable engagement with agreed SLAs and proven governance models

• Impeccable quality, first time acceptance and on-time delivery record

• Commitment to long-term sustainable client relationships

Light Detection and Ranging - FECA© 2013 Infotech Enterprises LiDAR stands for Light Detection and...

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Transcript of Light Detection and Ranging - FECA© 2013 Infotech Enterprises LiDAR stands for Light Detection and...