Miracle-dz/UniFAR-FTUs huggingface dataset:
When is a mechanical control system kinematic?

The author deals with simple mechanical control systems (A.D. Lewis and R.M. Murray, 1997), possibly with constraints (A.D. Lewis, 1997). These systems are naturally characterised by having forces as inputs. However, in the current literature there is a tendency to replace force inputs with velocity inputs. This is sometimes a justifiable step, and serves to simplify somewhat certain applications. However, one must be careful as: (1) sometimes, very often in fact, this simplification is comprehensively not possible (as we demonstrate); and (2) the two different control problems which result, one with force inputs and one with velocity inputs, will never be equivalent with the same class of inputs (unless one makes the impractical restriction of smooth inputs). Nevertheless, if one properly considers the classes of inputs for both problems, it is possible to give a simple, computationally tractable condition which determines when a system with force inputs can be reduced to one with velocity inputs. One of the main points made is that there is no correspondence, be it complete or approximate, between mechanical control systems, and so-called "nonholonomic" (i.e., driftless) control systems. A precise connection is made between those mechanical systems which are dynamic (i.e., have forces as inputs) and those which are kinematic (i.e., have velocities as inputs).
Real-Time Identification of Periodic Signals using the Recursive Variable Projection Algorithm

This paper presents a real-time parameter identification algorithm for periodic signals, based on the recursive variable projection (RVP) algorithm. The recursive implementation enables the tracking of time-varying parameters. The signal model is linear with respect to the amplitude parameters while being nonlinear with respect to the phase and frequency. This feature motivates the use of a variable projection based approach. Its performance is tested using Monte Carlo simulations and the results are compared with those obtained by a multiobjective Gauss-Newton (MGN) algorithm. Furthermore, the RVP algorithm is applied to measurement data acquired by a MEMS accelerometer and it is demonstrated that it can successfully track time-varying linear and nonlinear parameters.
A Novel Converter-level Online Junction Temperature Estimating Method for SiC MOSFETs Based on the Current Oscillation of DC and AC sides in a Single Phase Inverter

SiC power devices have been increasingly used in industrial applications. Junction temperature estimating is the basis of high reliability operation for SiC devices, since thermal stress is one of the dominating failure inducing factors. Thermal sensitive electrical parameter (TSEP) methods have been widely used for junction temperature estimating for the advantage in low invasiveness and fast response speed. However, conventional TSEP methods merely focus on a single semiconductor device instead of a converter, which results in high cost and difficulty in integration. Low sensitivity is another limitation. To solve the problems, a high-sensitivity converter-level online junction temperature estimating method is proposed in this paper based on the current oscillation (ΔiOS) of DC and AC sides in a single-phase inverter. Theoretical analysis is provided to illustrate why ΔiOS can serve as a converter-level junction temperature (Tj) indicator. The relationship between ΔiOS and Tj is obtained by experiment for calibration based on a dual pulse test. Online experiment for Tj estimating based on a single-phase inverter is provided to verify the effectiveness of the proposed method.
Cases of Soft Switching in a Series Resonant Balancing Converter for Bipolar DC Grids

Balancing converters are an integral part of a bipolar dc grid. Resonant converter topologies are interesting for power electronics engineers due to their soft switching capabilities. A series resonant converter topology is promising as a balancing converter in a bipolar dc grid. The series resonant converter is usually a non-inverting topology. However, in the balancing converter application, the converter is used as an inverting type, like a buck-boost converter topology. In this paper, the soft switching capabilities of this converter are shown and analyzed for four distinct converter modulation schemes.
View Selection for Industrial Object Recognition

The last industrial revolutions and the digital transformation have led to a rise of robotics and to the emergence of the concept of digital twin. A major challenge falls within the update of this virtual representation, so that the supervision operator and the system itself can take appropriate decisions. One way to achieve that is to take advantage of the multi-robot perception capabilities by merging their individual observations to collectively enhance object recognition and robot environmental understanding. Since object recognition strongly depends on the viewing angles, one challenge deals with identifying the most relevant camera poses containing the most relevant information about the nature of the object. In this paper we propose a smart view selection approach which aims at determining the poses of the cameras and the number of the most informative views while maximising the object recognition. Based on a synthetic view dataset of traditional industrial objects, we adopt a clustering-based approach for maximising the inter-class distance and minimising the intra-class one. To do so, we compute a score for each view based on the Fowlkes-Mallows Index. This leads us to order the dataset and select a subset of views maximising the score. Then, this subset is used as a training dataset for a knn-classifier. The results, presented in terms of F1-score metric, are promising and highlight the relevance of our work: i) our smart selection enables the collection of a limited number of the most informative camera poses for object recognition; ii) feature extraction from a pre-trained CNN combined with a clustering algorithm allows the separability of industrial object categories; iii) our approach is robust since it provides good performances while the camera poses are in the neighbourhood of the exact camera positions provided by our processing pipeline.
Formation of electric-field domains inGaAs∕AlxGa1−xAsquantum cascade laser structures

The current-voltage I-V characteristics of GaAs/AlxGa1−xAs quantum cascade laser structures QCLSs are found to exhibit current plateaus with discontinuities for voltages below threshold. The number of current discontinuities is correlated with the number of periods of the QCLS, suggesting the formation of electric-field domains that span the entire structure. A self-consistent calculation of the conduction band profile and corresponding electronic wave functions shows that the low-field domain is related to resonant tunneling between the ground state g in the active region and the lowest energy state in the adjacent, downstream injector i1. For x=0.33 x=0.45 , the high-field domain is formed for resonant tunneling between g and the first second excited state i2 i3 in the injector region. A comparison of the experimental data with the calculated conduction band profile shows that a significant field inhomogeneity within each period shifts the voltage range, for which the resonance condition is fulfilled, to much lower voltages than expected for a homogeneous field distribution.
Comparison of Circular Coil, Double-D Coil, and 85 kHz Self-Resonant Coil in Road Embedment for Dynamic Wireless Power Transfer

There have been various types of transmitter coils proposed for dynamic wireless power transfer. This study compared three types of coils: circular (spiral) coil, DD coil, and 85 kHz self-resonant coil. The coil performance was evaluated under an ideal environment on the ground side and after coil embedment in the road, and the characteristics of each coil were clarified. In this study, the allowable current value of the litz wire was evaluated as a constraint condition. The results of the verification using actual coils showed that when the input voltage was increased to around the allowable current value of the litz wire, the 85 kHz self-resonant coil obtained approximately 30 kW of power at the input voltage conversion value of 1160 V. The output power was approximately 8 kW higher than that of the circular coil and the DD coil. It was also found that the circular coil and DD coil showed almost similar power feeding performance when compared.
Load-Side Acceleration Control for Geared Motors with Unknown Backlash and Nonlinear Friction

This paper proposes a load-side acceleration control scheme for geared motors affected by unknown backlash and friction. A backlash-deactivated disturbance observer (BDDOb) is proposed to achieve load-side acceleration control while ensuring quick traversing of backlash. The BDDOb works by executing conditional estimation-compensation of load disturbances, and is driven by a backlash detection scheme based on torsion torque sensing which does not require any information on the backlash gap width. In addition, a variable-order force-position-integrated disturbance observer (VOFPIDO) is proposed to quickly compensate nonlinear friction without requiring information of the nonlinear friction magnitude by applying velocity-dependent switching. Experimental results prove the effectiveness of the proposed method.
Graph Attention Network on Extracting Feature from Simplified Molecular-Input Line-Entry System for HIV Classification

Human immunodeficiency virus targets the immune system and weakens people defenses against the variety of infections. Several research try to detect HIV but mostly used Protein as their input. However, the protein structure is hard to understand to the complexity of protein, in this paper we used different approach by using Simplified Molecular-Input Line-Entry System (SMILES). The SMILES provides easier analysis because the linear structure compared to Protein structure. In this paper we proposed Graph Attention Network on extracting Simplified Molecular-Input Line-Entry System (SMILES). We compared our proposed method to renown library to extract SMILES features namely RDKIT. The result showed the GAT gave the best result in accuracy with the 96.5%. However, it has many disadvantages in handling the imbalanced data.
A Novel approach for Detection and Counting of Vehicles using CNN architectures

Recent years the usage of automobiles significantly increased in urban regions. As the usage increased, the traffic jams also became a major issue in day-to-day life. Even governments tried to increase the infrastructure and failed mitigating the traffic issues. In this research, we are proposing a Deep learning approach to find out the density of the vehicle flow in a fully traffic regions. In order to do this project, we are proposing VGG16 a CNN architecture for vehicle recognition (classification) and proposing Yolo for detection of vehicles. Further we employed the OpenCV techniques for 1) Adaptive background subtraction 2) image segmentation 3) vehicle counting 4) vehicle tracking purpose. The primary objectives of this proposed system is: 1) the ability to count vehicles 2) its efficiency, as it produces accurate results. For this we are using a Traffic and Congestions (TRANCOS) dataset which consists of 1244 images of different vehicles, for training and validation purpose and also we gathered an open source traffic surveillance video for live tracking of vehicles and counting. The proposed system achieved 95.77% model accuracy and 98% of ROC curve for both bike and car classes. Further we validated our model using Accuracy, precision, Recall, F1 metrics and achieved 96% accuracy.
Modeling and Analysis of Electrical-Thermal Performance of the Contact Surface of Coaxial Connectors at High Frequency and High Power

In high frequency and high-power signal transmission, the quality of the signal is negatively impacted by high temperatures of the contact surfaces in coaxial connectors. The voltage-temperature (V-T) relation is often used to calculate the maximum temperature of electrical contacts, but the measured temperature may not match the theoretical value for high frequency and high-power signal transmission. In this study, a model of the temperature distribution of the contact surface of a coaxial connector was developed. Finite element analysis (FEA) simulations were performed to evaluate the influence of the power and frequency on the temperature of the contact surface, and the electrical and thermal performances of sample coaxial connectors were analyzed. Experiments were conducted to measure the contact temperature for various power and frequency levels. By comparing the measured contact temperature of the test samples with the values calculated using the V-T equation, it was found that the equation may not yield accurate predictions for connectors operating at high frequency and high power. These results show significantly improved predictive capability in high frequency and high power.
Remote System in Semiconductor Industry

In conventional semiconductor machine operation method, it is required the operator physically to be in front of the machine. The operator needs to walk from one machine to another machine just to make the machine run. Without operator, the machine cannot run smoothly especially if there are many machine stoppages. Because of this issue, the engineer needs to work on how to reduce the machine stoppages and improve the machine performance. In certain circumstances, the machine has a limitation, and the machine stoppages cannot be improved anymore especially to the old machine generation. To maintain the old machine generation performance is very challenging and sometime the machine spare part is also obsoleted. By introducing the remote system in the semiconductor, it will help to solve the machine limitation issue. From the control room, the operator able to clear the machine stoppages without physically need to be in front of the machine. It will help to reduce operator workload, reduce the machine downtime, improve the man-to-machine ratio and at the end reduce the cost. Fig. 1 below shown the comparison between with and without remote system. The number of operators can be reduced significantly, and the movement of the operator also can be reduced. Bear in mind, not all the machine stoppages can be remoted. The remote system also has its own limitation. For example, change material, change lot, and change the machine part cannot be done remotely. Its still require operator physically to be in front of the machine.
A Delay Modulation Method to Improve the Time Resolution for a 32 × 32 Array of MPPC Image Sensor

The array laser detector can achieve three-dimensional (3D) flash imaging via multi-channel parallel ranging, which significantly improves the imaging speed. However, the large number of the array makes it difficult to improve the ranging resolution through circuit evolution and data processing, even the imaging speed will be sacrificed. To overcome the problem, a delay modulation method on the transmitter of the laser is proposed in this study. The method is realized by using a $32\times 32$ Multi-Pixel Photon Counter (MPPC) array and an improved phase-shifted clocks method. We eventually achieve 1024-channel 3D imaging that exceeds the depth resolution of the system. Experimental results show that, the Root Mean Square Error (RMSE) of plane fitting with delay modulation is 2.39-5.03 cm, which has come down to 48.6% than those without delay modulation. Using the delay modulation method, a target with a depth difference of about 4 cm can be clearly distinguished by 3D imaging at a distance of 5 m, even if the minimum resolution of the system is 5 cm. Results also demonstrate that the proposed method can easily and effectively enhance the measurement accuracy of 3D flash imaging.
Robust Task-Priority Impedance Control for Vehicle-Manipulator Systems

Enabling vehicle-manipulator systems to perform complex and precise intervention operations requires a robust control framework capable of handling redundancy and interaction forces. In addition, it is desirable that the method allows completion of several tasks with a strict prioritization to keep safety critical tasks unaffected by other goals. In this paper, a control method is developed for a broad class of vehicle-manipulator systems, with the main use case being floating base underwater vehicle manipulator systems subject to hydrodynamic forces. In underwater applications, large model uncertainties will be present due to hydrodynamic and hydrostatic effects, unknown disturbances and modelling errors. This means that a viable solution must be robust to disturbances and modelling errors, while also satisfying strict task priorities and compliant contact behaviour. To achieve this, a robust impedance based task-priority control method is presented, and its stability and robustness properties are proven. The method is validated in a simulation of an articulated intervention autonomous underwater vehicle (AIAUV).
Micro Heater Design Procedure with Backside Etching for Medical Applications

The incorporation of micro-heaters in medical analysis devices significantly aided in the miniaturization of such devices and shortened the processing time. Despite the fact that various micro-heater designs have been proposed, a high-speed heating rate for micro-heaters remain a challenge. The reduction of thermal mass allows for this high-speed to be accomplished. Furthermore, backside etching of the substrate is critical in increasing the rate of temperature change in thin-film micro heaters. This will speed up the thermal cycle, paving the way for high-speed, portable, and cost-effective medical devices like the polymerase chain reaction (PCR). The size of the backside opening, on the other hand, should be carefully chosen to ensure the heater's rigidity. The larger the backside opening, the faster the thermal change and the lower the stiffness of the chip. An accurate simulation investigation was performed in this study using the CoventorWare software tool to obtain the optimal back side design for the designed micro heater in which the temperature change process is accelerated while the chip's strength is maintained. This study allows us to achieve a high-strength, high-speed micro-heater with superior efficiency. The heater's dimensions are designed to warm up a chip of size 30x40 mm in accordance with Peltier's chip size. For the provided heater dimensions, a series of squares with side lengths of 2.5 mm per square and a distance of 1 mm between each square was found to be the best design for the backside etching. It raises the heating rate to 22 °C/s and allows the heater to withstand pressure up to 1.8 MPa.
A Force-Based Control Approach for the Non-Prehensile Cooperative Transportation of Objects Using Omnidirectional Mobile Robots

The increasing complexity and scale of today's tasks assigned to autonomous robotic systems entails that it is often neither possible nor efficient to accomplish the given task in a reliable and performant manner by utilizing a sophisticated individual robot. Instead, distributed robotics brings about the potential to master complex tasks by means of comparatively simple robots. This anticipation is enhanced by continuous advances in communication, processing units, and sensors. In that regard, this paper considers the model problem of non-prehensile cooperative transportation of objects. Relying on optimization-based methods, a group of omnidirectional mobile robots is enabled to push arbitrary polygonal, possibly non-convex, objects along a desired path in the plane. In contrast to some of the authors' previous work, this paper novelly proposes an approach to manipulate the object based on force-level considerations. This is of particular interest since it provides the opportunity to naturally consider heterogeneous robotic groups or to handle more intricate scenarios such as transporting deformable objects. The proposed scheme's functionality and versatility is demonstrated through simulation scenarios.
Energy Consumption Comparison of Some WSN OOK Transmitters Through Minimum Energy Coding

Energy efficiency is one of the most important criteria for wireless sensor networks since they consist of energy constrained sensor nodes. Minimum Energy coding (ME-Coding) is proposed to improve the energy efficiency of On-Off Keying (OOK) transmitter in the literature. In this study, the four single ended OOK transmitters are compared in terms of total energy consumption. The results show that the 433 MHz OOK transmitter is the least energy consuming among of them.
Interturn short circuit modelling in dual three-phase PMSM

In this study, model of a multi-phase permanent magnet synchronous motor is demonstrated. The model is designed to allow simulations of inter-turn short circuit faults of various severity. The considered multi-phase motor is connected as a dual three-phase system. In this case, stator windings are divided into two electrically separated sub-systems. Nevertheless, the magnetic coupling between sub-systems needs to be taken into account in general. The motor model is designed to take into account the exact stator coils distribution. In this case motor uses combination of serial and parallel connections. Model is implemented in MATLAB/Simulink using SimScape environment. The paper also shows a comparison of the behavior of a real PMS motor and derived model behavior.
Development of a FHE Based Temperature and Humidity Sensing System for Asset Monitoring Applications

A novel flexible hybrid electronics (FHE) based system was developed to monitor temperature and humidity inside any storage container. The primary components for the fabrication of the temperature and humidity sensing system prototype include a flexible 5-mil-thick Kapton polyimide substrate with high temperature withstanding capability and high tensile strength, as well as a conductive silver ink. The conductive traces were screen printed on the Kapton substrate and the components for measuring and recording temperature and humidity were attached to the printed traces to fabricate the system. Various tests were performed on the printed traces based on IPC-TM650 and ASTM standards to investigate the capability of the system. Mechanical tests including bending and elongation deformations, moisture and insulation resistance tests were performed to understand the flexibility, durability and environmental effects on the system. The results obtained from the mechanical bending tests showed a negligible average resistance change of 0.1% in each cycle when the printed coupon was bent by 180° for 200 cycles. In addition, a Young's modulus of 2.6 GPa was calculated from the elongation test. The moisture and insulation resistance test confirmed a stable resistance of ∼18 MΩ for the PFS test coupon when temperature was varied from 25°C to 65 °C at a maximum humidity of 90% RH repeated for 20 cycles in 7 days. This printed FHE based temperature and humidity monitoring system can be employed in several applications in the food, pharmaceutical, agriculture, automotive, and defense industries.