Rafal Perz

Dr. Rafal Perz


Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

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

Representative Publications

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8 October 2018 in Aircraft Engineering and Aerospace Technology
Verified
Journal Article
Closed access
RPRafal Perz
Rafal Perz
KWKacper Wronowski
Kacper Wronowski
Purpose: The purpose of this study is to show the potentials of a cost-effective unmanned aerial vehicles (UAV) system for agriculture industry. The current population growth rate is so vast that farming industry must be highly efficient and optimized. As a response for high quality food demands, the new branch of the agriculture industry has been formed – the precision agriculture. It supports farming process with sensors, automation and innovative technologies. The UAV advantages over regular aviation are withering. Not only they can fly at lower altitude and are more precise but also offer same high quality and are much cheaper. Design/methodology/approach: The main objective of this project was to implement an exemplary cost-effective UAV system with electronic camera stabilizer for gaining useful data for agriculture. The system was based on small, unmanned flying wing able to perform fully autonomous missions, a commercially available camera and an own-design camera stabilizer. The research plan was to integrate the platform and run numerous experimental flights over farms, fields and woods collecting aerial pictures. All the missions have been planned to serve for local farming and forest industries and cooperated with local business authorities. Findings: In preliminary flight tests, the variety of geodetic, forest and agriculture data have been acquired, placed for post processing and applied for the farming processes. The results of the research were high quality orthophoto maps, 3D maps, digital surface models and images mosaics with normalized difference vegetation index. The end users were astonished with the high-quality results and claimed the high importance for their business. Originality/value: The case study results proved that this kind of a small UAV system is exceptional to manage and optimize processes at innovative farms. So far only professional, high-cost UAV platforms or traditional airships have been applied for agriculture industry. This paper shows that even simple, commercially available equipment could be used for professional applications.

11 November 2013 in SAE International Journal of Advances and Current Practices in Mobility
Verified
Conference Paper
Closed access
JFJason L. Forman
Jason L. Forman
FLFrancisco Lopez-Valdes
Francisco Lopez-Valdes
DLDavid J. Lessley
David J. Lessley
PRPatrick Riley
Patrick Riley
MSMark Sochor
Mark Sochor
KHKazuo Higuchi
Kazuo Higuchi
In far-side impacts, head contact with interior components is a key injury mechanism. Restraint characteristics have a pronounced influence on head motion and injury risk. This study performed a parametric examination of restraint, positioning, and collision factors affecting shoulder belt retention and occupant kinematics in far-side lateral and oblique sled tests with post mortem human subjects (PMHS). Seven PMHS were subjected to repeated tests varying the D-ring position, arm position, pelvis restraint, pre-tensioning, and impact severity. Each PMHS was subjected to four low-severity tests (6.6 g sled acceleration pulse) in which the restraint or position parameters were varied and then a single higher-severity test (14 g) with a chosen restraint configuration (total of 36 tests). Three PMHS were tested in a purely lateral (90° from frontal) impact direction; 4 were tested in an oblique impact (60° from frontal). All subjects were restrained by a 3-point seatbelt. Occupant motion was tracked with a 3D optoelectric high speed motion capture system. For all restraint configurations, the 60° oblique impact angle was associated with greater lateral head excursion than the 90° impact angle. This unexpected result reflects the increased axial rotation of the torso in the oblique impacts, which allowed the shoulder to displace more relative to the shoulder belt and thus the head to displace more relative to the sled buck. Restraint engagement of the torso and shoulder was actually greater in the purely lateral impacts than in the oblique impacts. Pretensioning significantly reduced lateral head excursion (175 mm average in the low-severity tests across all restraint configurations).

1 January 2015 in Journal of the Mechanical Behavior of Biomedical Materials
Verified
Journal Article
Closed access
RPRafal Perz
Rafal Perz
JTJacek Toczyski
Jacek Toczyski
DSDamien Subit
Damien Subit

5 January 2023 in Electronics
Verified
Journal Article
Open access
PDF file
Łukasz PopekŁukasz Popek
Łukasz Popek
RPRafal Perz
Rafal Perz
GGGrzegorz Galiński
Grzegorz Galiński
For most wild animals, the peak activity occurs during the night hours—their observation is possible only with the use of specialized equipment. Advancements in technology and the availability of thermal sensing devices allow researchers to examine wildlife. This study compares different methods for animal detection in thermal camera images including classical (HOG/SVM) and based on deep neural networks (Faster RCNN and YOLO). A comparison was performed to indicate the most beneficial mean Average Precision (mAP) for different levels of Intersection over Union (IoU) coverage thresholds and sensitivity (Recall). The results were evaluated on a scratch dataset containing two animal families (Cervidae and Suidae). The models were compared in terms of precision, recall, and training time. After a series of tests, the achieved performance was very satisfying: for the YOLOv3 network, the obtained mAP was above 90% for IoU > 50%; for Faster R-CNN, the obtained mAP was 87%; and for HOG/SVM, the obtained mAP was 40%. The training time for HOG/SVM was under 1 min, for YOLOv3 it was around 50 min, and for Faster R-CNN it was around 60 min. This research provides an important starting point for the creation of a ground-based system for autonomous observation of migration and population numbers, which is a unique approach in the field of wildlife research.

13 May 2019 in Aircraft Engineering and Aerospace Technology
Verified
Journal Article
Closed access
JMJacek Mieloszyk
Jacek Mieloszyk
ATAndrzej Tarnowski
Andrzej Tarnowski
MKMichal Kowalik
Michal Kowalik
RPRafal Perz
Rafal Perz
WRWitold Rządkowski
Witold Rządkowski
Purpose: Additive manufacturing technology, also commonly called as 3D printing technology, is entering rapidly into the aerospace world and seems to be its future. Many manufacturing processes are replaced by this technology because the ease of use, low costs and new possibilities to make complicated parts. However, there are only few solutions which present manufacturing of structurally critical parts. Design/methodology/approach: Complete process of deriving loads, design of fitting geometry, numerical validation, manufacturing and strength testing was presented. The emphasis was made to show specific features of 3D technology in printed fittings for UAV. Findings: The research confirms that the technology can be used for the application of fittings manufacturing. Attention needs to be paid, during the design process, to account for specific features of the 3D printing technology, which is described in details. Practical implications: Without a doubt, additive manufacturing is useful for manufacturing complicated parts within limited time and with reduction cost. It was also shown that the manufactured parts can be used for highly loaded structures. Originality/value: The paper shows how additive manufacturing technology can be used to produce significantly loaded parts of airplanes’ structure. Only few such examples were presented till now.

13 March 2024 in Archives of Transport
Verified
Journal Article
Open access
PDF file
RPRafal Perz
Rafal Perz
Unmanned Aerial Vehicles (UAVs), also referred to as drones, are increasingly utilized in sectors such as surveillance, transportation, and entertainment. The global UAV market, projected to escalate to USD 70.7 billion by 2026, demonstrates a significant growth trajectory. However, alongside their functional utility, UAVs present substantial risk factors, notably in the domain of collisions with humans and other entities. These collision events are categorizable by operational context (military versus civilian) and flight phase (e.g., takeoff, landing). Contributory factors to these occurrences include operator errors, equipment malfunctions, and prevailing environmental conditions. Incidents involving human-UAV collisions are of particular concern. The severity of impact is contingent upon UAV specifications and the conditions of operation. Predominantly accidental, these incidents accentuate escalating safety concerns in the burgeoning UAV sector. This manuscript endeavors to examine the risks inherent in UAV operations, with an emphasis on human-UAV collision scenarios. A review of extant literature is conducted to formulate safety measures and amplify awareness regarding UAV-associated hazards. The manuscript is methodically structured to encompass scenarios of hazard within UAV operations, historical accounts of collisions, and an analysis of their causative factors and subsequent ramifications. Additionally, it scrutinizes the legislative framework governing UAV operations on a global scale, with a specific focus on Europe and Poland. The discourse extends to the examination of physical impacts resultant from UAV-human collisions, exploring diverse scenarios and resultant injuries. The conclusion delineates the necessity for a comprehensive understanding of UAV-associated risks and advocates for strategies to mitigate collision risks. With UAVs becoming increasingly integrated into everyday functionalities, addressing potential threats assumes critical importance. Achieving equilibrium between technological advancement and public safety is paramount. Effective regulation of UAVs necessitates a multifaceted approach, incorporating legal and procedural constraints to curtail accident rates. The manuscript underscores the imperative for established weight and height thresholds for UAVs, implementation of protective measures, and enhancement of public cognizance. Further investigative efforts are imperative to elucidate the long-term repercussions of UAV-induced injuries and the risks posed by emerging UAV models, underscoring the importance of responsible UAV utilization and the ongoing necessity for research in this domain.