Axel Willekens

Dr. Axel Willekens

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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13 September 2023 in Biosystems Engineering
Verified
Journal Article
Closed access
WVWout Vierbergen
Wout Vierbergen
AWAxel Willekens
Axel Willekens
DDDonald Dekeyser
Donald Dekeyser
SCSimon Cool
Simon Cool
FWFrancis Wyffels
Francis Wyffels

30 June 2025 in Journal of Field Robotics
Verified
Journal Article
Closed access
AWAxel Willekens
Axel Willekens
STSébastien Temmerman
Sébastien Temmerman
FWFrancis Wyffels
Francis Wyffels
JPJan G. Pieters
Jan G. Pieters
SCSimon R. Cool
Simon R. Cool

8 February 2025 in Waste Management
Verified
Journal Article
Closed access
NBNathalie Bernaert
Nathalie Bernaert
EREvy De Rycke
Evy De Rycke
MHMarijke Hunninck
Marijke Hunninck
GVGeertrui Vlaemynck
Geertrui Vlaemynck
EPEls Van Pamel
Els Van Pamel
MLMarc De Loose
Marc De Loose

19 March 2025 in Sensors
Verified
Journal Article
Open access
PDF file
VCValentijn De Cauwer
Valentijn De Cauwer
SCSimon Cool
Simon Cool
AWAxel Willekens
Axel Willekens
STSébastien Temmerman
Sébastien Temmerman
DNDavid Nuyttens
David Nuyttens
SLSam Leroux
Sam Leroux
Soil compaction is a widespread problem, leading to soil degradation, yield losses, and adverse environmental impacts. Nowadays, various measurement methods exist to assess and map soil compaction, with vertical cone penetration resistance measurements being one of the most commonly used. This method is easy, rapid, inexpensive, and generally accepted. However, manual penetration resistance measurements are time-consuming, labor-intensive, and often less accurate due to inconsistent penetration speed. To address these limitations, an automated penetrometer was developed and integrated on an autonomous robot platform, paving the way for high-resolution compaction mapping as a starting point for precision subsoiling to remediate soil compaction. The performance of this setup was validated in controlled and field conditions against a hand-held penetrometer. Therefore, experiments were conducted in soil-filled cylinders and on plots of a long-term field experiment, including measurements across spraying tracks. The automated penetrometer demonstrated high correlations with the hand-held device under controlled conditions, though the correlation was somewhat lower in the field due to the soil’s heterogeneity. Deviations between the two measurement devices were likely caused by the inconsistent insertion speed of the hand-held penetrometer, particularly in soils with high penetration resistance. Both penetrometers successfully identified the plow pan at a depth of 30–40 cm but were unable to clearly show the effect of the long-term presence of spraying tracks.

4 February 2025 in Precision Agriculture
Verified
Journal Article
Closed access
PDF file
AWAxel Willekens
Axel Willekens
BCBert Callens
Bert Callens
FWFrancis Wyffels
Francis Wyffels
JPJan Pieters
Jan Pieters
SCSimon Cool
Simon Cool

3 October 2025 in IEEE Internet of Things Journal
Verified
Journal Article
Closed access
CCCiem Cornelissen
Ciem Cornelissen
SCSander De Coninck
Sander De Coninck
AWAxel Willekens
Axel Willekens
SLSam Leroux
Sam Leroux
PSPieter Simoens
Pieter Simoens
This article presents an end-to-end, IoT-enabled robotic system for the nondestructive, real-time, and spatially resolved mapping of grape yield and quality (brix and acidity) in vineyards. The system features a comprehensive analytical pipeline that integrates two key modules: a high-performance model for grape bunch detection and weight estimation, and a novel deep learning framework for quality assessment from hyperspectral imaging (HSI) data. A critical barrier to in-field HSI is the “domain shift” caused by variable illumination. To overcome this, our quality assessment is powered by the light-invariant spectral autoencoder (LISA), a domain-adversarial framework that learns illumination-invariant features from uncalibrated data. We validated the system’s robustness on a purpose-built HSI dataset spanning three distinct illumination domains: controlled artificial lighting (lab), and variable natural sunlight captured in the morning and afternoon. Results show the complete pipeline achieves a recall (0.82) for bunch detection and an $R^{2}$ (0.76) for weight prediction, while the LISA module improves quality prediction generalization by over 20% compared with the baselines. By combining these robust modules, the system successfully generates high-resolution, georeferenced data of both grape yield and quality, providing actionable, data-driven insights for precision viticulture (PV).