Nikos Frangakis

Mr. Nikos Frangakis

innovation, iKnowHow (Greece), Athens, Attikí, Greece
orcid

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

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

Representative Publications

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28 October 2023 in Robotics
Verified
Journal Article
Open access
PDF file
KTKosmas Tsiakas
Kosmas Tsiakas
APAlexios Papadimitriou
Alexios Papadimitriou
EPEleftheria Maria Pechlivani
Eleftheria Maria Pechlivani
DGDimitrios Giakoumis
Dimitrios Giakoumis
NFNikos Frangakis
Nikos Frangakis
DTDimitrios Tzovaras
Dimitrios Tzovaras
Due to the accelerated growth of the world’s population, food security and sustainable agricultural practices have become essential. The incorporation of Artificial Intelligence (AI)-enabled robotic systems in cultivation, especially in greenhouse environments, represents a promising solution, where the utilization of the confined infrastructure improves the efficacy and accuracy of numerous agricultural duties. In this paper, we present a comprehensive autonomous navigation architecture for holonomic mobile robots in greenhouses. Our approach utilizes the heating system rails to navigate through the crop rows using a single stereo camera for perception and a LiDAR sensor for accurate distance measurements. A finite state machine orchestrates the sequence of required actions, enabling fully automated task execution, while semantic segmentation provides essential cognition to the robot. Our approach has been evaluated in a real-world greenhouse using a custom-made robotic platform, showing its overall efficacy for automated inspection tasks in greenhouses.

2 June 2024 in Smart Agricultural Technology
Verified
Journal Article
Open access
NGNikolaos Giakoumoglou
Nikolaos Giakoumoglou
EKEleni Kalogeropoulou
Eleni Kalogeropoulou
CKChristos Klaridopoulos
Christos Klaridopoulos
EPEleftheria Maria Pechlivani
Eleftheria Maria Pechlivani
Panagiotis ChristakakisPanagiotis Christakakis
Panagiotis Christakakis
DTDimitrios Tzovaras
Dimitrios Tzovaras

20 November 2023 in AI
Verified
Journal Article
Open access
PDF file
Nikolaos GiakoumoglouNikolaos Giakoumoglou
Nikolaos Giakoumoglou
EPEleftheria Maria Pechlivani
Eleftheria Maria Pechlivani
NFNikos Frangakis
Nikos Frangakis
DTDimitrios Tzovaras
Dimitrios Tzovaras
Early detection and efficient management practices to control Tuta absoluta (Meyrick) infestation is crucial for safeguarding tomato production yield and minimizing economic losses. This study investigates the detection of T. absoluta infestation on tomato plants using object detection models combined with ensemble techniques. Additionally, this study highlights the importance of utilizing a dataset captured in real settings in open-field and greenhouse environments to address the complexity of real-life challenges in object detection of plant health scenarios. The effectiveness of deep-learning-based models, including Faster R-CNN and RetinaNet, was evaluated in terms of detecting T. absoluta damage. The initial model evaluations revealed diminishing performance levels across various model configurations, including different backbones and heads. To enhance detection predictions and improve mean Average Precision (mAP) scores, ensemble techniques were applied such as Non-Maximum Suppression (NMS), Soft Non-Maximum Suppression (Soft NMS), Non-Maximum Weighted (NMW), and Weighted Boxes Fusion (WBF). The outcomes shown that the WBF technique significantly improved the mAP scores, resulting in a 20% improvement from 0.58 (max mAP from individual models) to 0.70. The results of this study contribute to the field of agricultural pest detection by emphasizing the potential of deep learning and ensemble techniques in improving the accuracy and reliability of object detection models.

5 July 2023
Verified
Conference Paper
Open access
IKIason Katsamenis
Iason Katsamenis
ASAthanasios Sakelliou
Athanasios Sakelliou
NBNikolaos Bakalos
Nikolaos Bakalos
Eftychios ProtopapadakisEftychios Protopapadakis
Eftychios Protopapadakis
CKChristos Klaridopoulos
Christos Klaridopoulos
Dimitris K KalogerasDimitris K Kalogeras
Dimitris K Kalogeras
Potholes on the road surface are a significant safety hazard and can cause severe damage to vehicles. Identifying and repairing potholes is a challenging task that requires efficient and accurate methods. In recent years, deep learning models, such as U-Nets and transformers, have been used for image segmentation tasks with promising results. This paper proposes a transformer-based model and in particular the SegFormer framework, for pothole segmentation using high-resolution images captured from a road inspection vehicle. The proposed network outperformed the traditional U-Net model that demonstrates state-of-the-art performance in various segmentation tasks, achieving an average F1-score close to 80%. The results show that the proposed method can effectively identify and localize potholes, providing a useful auxiliary tool for road maintenance and safety.