Alejandro Agostini

Dr. Alejandro Agostini

orcid

Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 February 2019 in Remote Sensing
Verified
Journal Article
Open access
PDF file
MFMaximilian Freudenberg
Maximilian Freudenberg
NNNils Nölke
Nils Nölke
AAAlejandro Agostini
Alejandro Agostini
KUKira Urban
Kira Urban
Florentin WörgötterFlorentin Wörgötter
Florentin Wörgötter
CKChristoph Kleinn
Christoph Kleinn
Oil and coconut palm trees are important crops in many tropical countries, which are either planted as plantations or scattered in the landscape. Monitoring in terms of counting provides useful information for various stakeholders. Most of the existing monitoring methods are based on spectral profiles or simple neural networks and either fall short in terms of accuracy or speed. We use a neural network of the U-Net type in order to detect oil and coconut palms on very high resolution satellite images. The method is applied to two different study areas: (1) large monoculture oil palm plantations in Jambi, Indonesia, and (2) coconut palms in the Bengaluru Metropolitan Region in India. The results show that the proposed method reaches a performance comparable to state of the art approaches, while being about one order of magnitude faster. We reach a maximum throughput of 235 ha/s with a spatial image resolution of 40 cm. The proposed method proves to be reliable even under difficult conditions, such as shadows or urban areas, and can easily be transferred from one region to another. The method detected palms with accuracies between 89% and 92%.

30 April 2009 in Robotics and Autonomous Systems
Verified
Journal Article
Closed access
FWF. Wörgötter
F. Wörgötter
AAAlejandro Agostini
Alejandro Agostini
NKN. Krüger
N. Krüger
NSN. Shylo
N. Shylo
BPB. Porr
B. Porr

1 June 2017 in Artificial Intelligence
Verified
Journal Article
Closed access
AAAlejandro Agostini
Alejandro Agostini
CTCarme Torras
Carme Torras
FWFlorentin Wörgötter
Florentin Wörgötter

1 June 2017 in Computers and Electronics in Agriculture
Verified
Journal Article
Open access
AAAlejandro Agostini
Alejandro Agostini
GAGuillem Alenyà
Guillem Alenyà
AFAndreas Fischbach
Andreas Fischbach
HSHanno Scharr
Hanno Scharr
FWFlorentin Wörgötter
Florentin Wörgötter
CTCarme Torras
Carme Torras
A cognitive system to autonomously control the growth of plants is proposed.The system integrates artificial intelligence and robotic techniques.Decisions are made using symbolic planning and machine learning.Plants are modelled using 3D model acquisition of deformable objects (leaves).Action rules are learned during run-time under the guidance of a human gardener. In large industrial greenhouses, plants are usually treated following well established protocols for watering, nutrients, and shading/light. While this is practical for the automation of the process, it does not tap the full potential for optimal plant treatment. To more efficiently grow plants, specific treatments according to the plant individual needs should be applied. Experienced human gardeners are very good at treating plants individually. Unfortunately, hiring a crew of gardeners to carry out this task in large greenhouses is not cost effective. In this work we present a cognitive system that integrates artificial intelligence (AI) techniques for decision-making with robotics techniques for sensing and acting to autonomously treat plants using a real-robot platform. Artificial intelligence techniques are used to decide the amount of water and nutrients each plant needs according to the history of the plant. Robotic techniques for sensing measure plant attributes (e.g. leaves) from visual information using 3D model representations. These attributes are used by the AI system to make decisions about the treatment to apply. Acting techniques execute robot movements to supply the plants with the specified amount of water and nutrients.

1 July 2010
Verified
Conference Paper
Open access
AAAlejandro Agostini
Alejandro Agostini
ECEnric Celaya
Enric Celaya
Recent approaches to Reinforcement Learning (RL) with function approximation include Neural Fitted Q Iteration and the use of Gaussian Processes. They belong to the class of fitted value iteration algorithms, which use a set of support points to fit the value-function in a batch iterative process. These techniques make efficient use of a reduced number of samples by reusing them as needed, and are appropriate for applications where the cost of experiencing a new sample is higher than storing and reusing it, but this is at the expense of increasing the computational effort, since these algorithms are not incremental. On the other hand, non-parametric models for function approximation, like Gaussian Processes, are preferred against parametric ones, due to their greater flexibility. A further advantage of using Gaussian Processes for function approximation is that they allow to quantify the uncertainty of the estimation at each point. In this paper, we propose a new approach for RL in continuous domains based on Probability Density Estimations. Our method combines the best features of the previous methods: it is non-parametric and provides an estimation of the variance of the approximated function at any point of the domain. In addition, our method is simple, incremental, and computationally efficient. All these features make this approach more appealing than Gaussian Processes and fitted value iteration algorithms in general.

14 July 2020 in IEEE Robotics and Automation Letters
Verified
Journal Article
Closed access
AAAlejandro Agostini
Alejandro Agostini
MSMatteo Saveriano
Matteo Saveriano
DLDongheui Lee
Dongheui Lee
JPJustus Piater
Justus Piater
Current approaches combining task and motion planning require intensive geometric and symbolic reasoning to find feasible motions for task execution. The poor expressiveness of task planning domains for characterizing geometric changes with actions and the difficulties faced by current approaches to efficiently identify motion dependencies for plan execution produce expensive callings to motion planning on unfeasible actions and intensive reasoning to find realizable plans. In this work we combine two recent approaches to address these problems. Task planning is carried out using an object-centered description of geometric relations that consistently characterizes changes in the object configuration space. Plan execution is implemented using a symbol to motion hierarchical decomposition that depends on consecutive actions in the plan, rather than on single actions, which permits considering motion dependencies across plan actions for a successful execution.