Titelmaster Prof. Dr. Heiner Kuhlmann Dipl. Inform. Stefan Paulus The benefit of plant models for laser generated data - advantages of a symbiosis - Dipl

Titelmaster

Prof. Dr. Heiner KuhlmannDipl. Inform. Stefan Paulus

The benefit of plant models for laser generated data

- advantages of a symbiosis -

Dipl. Inf. Stefan PaulusInstitute of Geodesy und Geoinformation

Professorship of GeodesyUniversity of Bonn

Dipl. Inform. Stefan Paulus

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overview

•state of the art

•motivation

•problems and difficulties

•benefit of models

•perspective


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state of the art

Laserscanning of plants

• with airborne laserscanners• inertial system + GPS

• with ground based laserscanner• time of flight• phase shift

• in the laboratory•triangulation•structed light•with different geometric approaches

Omasa 2007


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state of the art

Omasa 2007

Omasa 2007

Extraction of various parameters:

• canopy height / mean tree height• distribution of leaf area in space• gap propability

• breast hight, diameter• carbon stocks from biomass estimation• shape analysis

Hosoi 2011

Omasa 2007

Omasa 2007


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state of the art

High resolution laser scanning of plants

Perceptron 2008


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motivation

today:• Derivation of morphological characteristics• Sensor fusion with RGB/IR/hyperspectral camera data• Reference system for calibration of other sensors• Observation of smallest changes to quantify plant response to changes in environment

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motivation

Llorens 2011

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Interaction is needed here!

In future:• usage directly in the field• target-actual comparison • prediction of parameters due to environment• adjustement of application and geometry

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problems and difficulties

1. Plant motion due to growth and vibrations

2. Change of plant structure und arrangement


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problems and difficulties

3. Occlusion due to sensor range and structure

4. Penetration of the laser beam and the plant surface

Rascher 2010

Perceptron 2008


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benefit of models

In short:•penetration improve the technique•occlusion ??? •change in structure ??? •plant motion ???

Benefit of physical (or FSPM) models• coordinate system for the plant• knowledge of structure• independant from sensor• connection between parts is known, this enables tracking

phyto-reference-system


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benefit of models

laserscans

model

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benefit of models

laserscans

model

high resolution plant puzzle aligned by underlying grammar system

•resolution•accuracy•geometry deformation•geometry parameters

•prediction•structure &•connection•interaction•growth &•development


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benefit of models

• local data can be aligned to the whole structure• by this, motion can be eliminated resp. is less disturbing• different sensors like RGB or hyperspectral camera can be fused in a more accurate way


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The idea in short

Laserscans Parameter Model

Problems

Errors

• Laser penetration• Occlussions• Accuracy• Resolution

• Errors• Uncertainty• no data


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The idea in short

Laserscans Parameter Pre-Model

Problems

Errors

Model Improved Parameters

Improved Laserdata

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advance advance

• prediction• sensor crossing• less errors

• plant coordinate system• less occlussion• better data connection


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with an application

Laserscans Parameter Pre-Model

Model Improved Parameters

Improved Laserdata

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Reliability


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perspective

• better results for known techniques• laserscanning under difficult circumstances• parameter extraction under bad point cloud conditions


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perspective

• better classification results for automated classification

leaf / stem classification by using SVM


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questions?

Thanks for your attention.Feel free to ask!


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Abstract

Laserscanning im Pflanzenbereich bietet höchste Auflösungen bei gleichzeitiger nicht invasiver Messung. Aus den resultierenden Punktwolken lassen sich Parameter ableiten, aus denen der Zustand der Pflanze bzgl. bspw. Trockenstress hervorgeht. Probleme ergeben sich aus der Eigenbewegung der Pflanze, der Dimension der Deformation (Wachstum und äußere Einflüsse), sowie einer unzureichenden 3D Zuordnung, die Fusion verschiedener Sensoren und Teilscans sowie Vergleich zu unterschiedlichen Zeitpunkten erschweren. Pflanzenmodelle bieten hier Lösungen durch Pflanzen-bezogene Koordinatensysteme, die zeitlich und räumliche Zuordnungen ermöglichen.

Laserscanning of plants provides highly accurate spatial resolution information together with non-invasive measurements. The resulting point cloud can be used to extract parameters describing plant state changes in response to i.e. drought stress. Problems resulting from plant motion, dimension of deformation caused by growth and outer influences as well as from insufficient 3D correspondence of scan parts among each other, complicates fusion of different sensors and scan parts and also the comparison of data of different dates. Plant models are solutions to these problems by providing plant-applied coordinate systems that enable spatio-temporal registration.

Documents

Titelmaster Prof. Dr. Heiner Kuhlmann Dipl. Inform. Stefan Paulus The benefit of plant models for laser generated data - advantages of a symbiosis - Dipl