Search Results (11)

The Printed Circuit Board (PCB) manufacturing industry is a rapidly expanding sector, fueled by advanced technologies and precision-oriented production processes. The placement of Surface-Mount Device (SMD) components in PCB assembly is efficiently automated using robots and design software-generated coordinate files; however, the PCB repair process remains significantly more complex and challenging. Repairing faulty PCBs, particularly replacing defective SMD components, requires high precision and significant manual expertise, making automated solutions both rare and difficult to implement. This study introduces a novel real-time machine vision-based coordinate estimation system designed for estimating the coordinates of SMD components during soldering or desoldering tasks. The system was specifically designed for Selective Compliance Articulated Robot Arm (SCARA) robots to overcome the challenges of repairing miniature PCB components. The proposed system integrates Image-Based Visual Servoing (IBVS) for precise X and Y coordinate estimation and a simplified laser triangulation method for Z-axis depth estimation. The system demonstrated accuracy rates of 98% for X and Y axes and 99% for the Z axis, coupled with high operational speed. The developed solution highlights the potential for automating PCB repair processes by enabling SCARA robots to execute precise picking and placement tasks. When equipped with a hot-air gun as the end-effector, the system could enable automated soldering and desoldering, effectively replacing faulty SMD components without human intervention. This advancement has the potential to bridge a critical gap in the PCB repair industry, improving efficiency and reducing dependence on manual expertise. Full article

Skin is the largest organ of the human body and holds the functions of sensing, protecting, and regulating. Since ancient times, people have decorated their skin by painting themselves, cutting, and using accessories to express their personality and aesthetic consciousness as a kind of artistic expression, one that shows the development and change of aesthetic consciousness. However, there are concerns regarding the inconvenience, high time cost, and negative body perception with traditional tattoos. In addition, the trend of skin decoration has gradually withdrawn due to a lack of intelligent interaction. In response to these problems, we proposed a wearable electronic skin tattoo that offers a novel means of communication and emotional expression for individuals with communication impairments, WABEIT. The tattoo uses skin-friendly PDMS as the base material, combines multi-mode sensing components such as silver wire circuit, a programmable Surface-Mounted Device (SMD), a thin-film-pressure sensor, and a heart rate sensor, and combines the embedded development board Arduino Nano for intelligent interaction, forming a wearable electronic interactive tattoo capable of sensing the environment, human–computer interaction, and the changeable performance of intelligent perception. The sensor is also equipped with a mobile power supply to support portability. The advantages of WABEIT are as follows: first, it avoids the pain, allergy, and long production process of traditional tattoos. Second, the patterns can adapt to different needs and generate feedback for users, which can effectively express personal emotions. Thirdly, the facility of removal reduces social discrimination and occupational constraints, which is especially suitable for East Asia. Experimental results indicate that the device exhibits a high sensitivity in signal response, a wide variety of pattern changes, and reliable interactive capabilities. The study demonstrates that the proposed design philosophy and implementation strategy can be generalized to the interactive design of other wearable devices, thereby providing novel insights and methodologies for human–computer interaction, electronic devices, and sensor applications. Full article

In this paper, a 3.2–3.6 GHz two-stage Doherty power amplifier (PA) module is proposed for fifth-generation (5G) massive multiple-input multiple-output (MIMO) base stations. A detailed design method and procedure for a compact and low-loss combiner suitable for the Doherty PA module are introduced. Based on the proposed combiner, a Doherty PA module is implemented using gallium nitride (GaN) transistors and surface-mounted devices (SMDs) with a packaged size of 8 × 8 mm². The proposed two-stage Doherty PA module achieves a 3 dB small-signal bandwidth of 3.1–3.9 GHz and a peak gain of 31.7 dB. From 3.2 to 3.6 GHz, the saturated output power is 40.4–41.1 dBm. Moreover, the measured saturated drain efficiency (DE) and 8 dB power back-off (PBO) DE reach 51–56.6% and 45.5–48.6%, respectively. Full article

This paper reports the design, fabrication, and performance of a hybrid piezoelectric planar micro-conveyor based on Micro-Electromechanical Systems (MEMS) bridge resonators and featuring 3D-printed vertical legs. The device includes two cooperating silicon plate resonators with an area of 5 × 1 mm², actuated by an integrated aluminum-nitride (AlN) piezoelectric thin film. An optimally designed array of 3D-printed projection legs was attached to the plates, to convert the standing-wave (SW) vertical vibrations into horizontal rotations or translations of the supported slider. An open-loop control strategy based on burst-type driving signals, with different numbers of sinusoidal cycles applied on each of the resonators, allowed the cooperation of the two bridges to set up prescribed trajectories of small flat objects, up to 100 mg, with positional accuracy below 100 nm and speeds up to 20 mm/s, by differential drive actuation. The effect of the leg tip and sliders’ surface finish on the conveyor performance was investigated, suggesting that further optimizations may be possible by modifying the tribological properties. Finally, the application of the micro-conveyor as a reconfigurable electronic system, driven by a preprogrammed sequence of signals, was demonstrated by delivering some surface-mount technology (SMD) parts lying on a 65 mg glass slider. Full article

The growing demand for the integration of surface mount design (SMD) antennas into miniaturized electronic devices has imposed increasing limitations on the structure dimensions. Examples include embedded antennas in applications such as on-board devices, picosatellites, 5G communications, or implantable and wearable devices. The demands for size reduction while ensuring a satisfactory level of electrical and field performance can be managed through constrained numerical optimization. The reliability of optimization-based size reduction requires utilization of full-wave electromagnetic (EM) analysis, which entails significant computational costs. This can be alleviated by incorporating surrogate modeling techniques, adjoint sensitivities, or the employment of sparse sensitivity updates. An alternative is the incorporation of multi-fidelity simulation models, normally limited to two levels, low and high resolution. This paper proposes a novel algorithm for accelerated antenna miniaturization, featuring a continuous adjustment of the simulation model fidelity in the course of the optimization process. The model resolution is determined by factors related to violation of the design constraints as well as the convergence status of the algorithm. The algorithm utilizes the lowest-fidelity model for the early stages of the optimization process; it is gradually refined towards the highest-fidelity model upon approaching convergence, and the constraint violations improve towards the preset tolerance threshold. At the same time, a penalty function approach with adaptively adjusted coefficients is applied to enable the precise control of constraints, and to increase the achievable miniaturization rates. The presented procedure has been validated using five microstrip antennas, including three broadband, and two circularly polarized structures. The obtained results corroborate the relevance of the implemented mechanisms from the point of view of improving the average computational efficiency of the optimization process by 43% as compared to the single-fidelity adaptive penalty function approach. Furthermore, the presented methodology demonstrates a performance that is equivalent or even superior to its single-fidelity counterpart in terms of an average constraint violation of 0.01 dB (compared to 0.03 dB for the reference), and an average size reduction of 25% as compared to 25.6%. Full article

This paper presents a low-cost architecture that allows for beamforming with antenna arrays installed onto unmanned aerial vehicles (UAVs). Beam switching is proposed to improve the antenna gain towards the ground station with two three-element arrays installed below the wings of the UAV. The electromagnetic modeling of the complete structure (UAV and integrated antennas) was performed with commercial electromagnetic simulator Ansys HFSS. The radiation patterns were synthesized with particle swarm optimization (PSO). By employing lumped surface-mount device (SMD) components and switches, the design of the feeder to deliver proper excitation coefficients to the antennas is presented, and its performance was assessed by simulations. The proposed approach is demonstrated to be very effective with low-cost production. Full article

Power semiconductors based on wide bandgap (WBG) devices are capable of fast switching and have low on-resistance. Accordingly, a fast sensor with a higher bandwidth is required for circuit inspection based on switch current measurements. Thus, it is necessary to have a current sensor in the printed circuit board (PCB) circuit for diagnosis and protection of the surface mount device (SMD) type circuit system. Accordingly, a pickup coil with the advantages of a high degree of sensor configuration freedom, wide bandwidth, and low cost can be a good alternative. This study analyzes the influence of coil shape and parameters on sensor design as a guideline for embedding a pickup coil in an SMD-type PCB circuit of a WBG power semiconductor-based, half-bridge structure. The mutual inductance and self-inductance values of the coil are considered large variables in the design of a sensor coil for simultaneously maintaining high bandwidth and sensor sensitivity. Therefore, magnetic and frequency response analyses were conducted to verify the correlation with inductance, the influence of coupling capacitance, and the influence of the magnetic field formation via the current flowing through the external trace inside the PCB. The coil model is verified and discussed through simulation and double pulse tests. Full article

Printed electronics is an expanding research field that can reach the goal of reducing the environmental impact on electronics exploiting renewable and biodegradable materials, like paper. In our work, we designed and tested a new method for fabricating hybrid smart devices on cellulose substrates by aerosol jet printing (AJP) and photonic curing, also known as flash lamp annealing (FLA), capable to cure low temperature materials without any damage. Three different cellulose-based materials (chromatographic paper, photopaper, cardboard) were tested. Multilayer capability and SMDs (surface mount devices) interconnections are possible permitting high flexibility in the fabrication process. Electrical and geometrical tests were performed to analyze the behavior of printed samples. Resulted resistivities are 26.3 × 10⁻⁸ Ω⋅m on chromatographic paper, 22.3 × 10⁻⁸ Ω⋅m on photopaper and 13.1 × 10⁻⁸ Ω⋅m on cardboard. Profilometer and optical microscope evaluations were performed to state deposition quality and penetration of the ink in cellulose materials (thicknesses equal to 24.9, 28.5, and 51 μm respectively for chromatographic paper, photopaper, and cardboard). Furthermore, bending (only chromatographic paper did not reach the break-up) and damp environment tests (no significant variations in resistance) where performed. A final prototype of a complete functioning multilayer smart devices on cellulose 3D-substrate is shown, characterized by multilayers, capacitive sensors, SMDs interconnections. Full article

This paper presents and discusses three different low-cost microstrip implementations of Schottky-diode detectors in W Band, based on the use of the Zero Bias Diode (ZBD) from VDI (Virginia Diodes, Charlottesville, VA, USA). Designs are based on a previous work of modeling of the ZBD diode. Designs also feature low-cost, easy-to-use tooling substrates (RT Duroid 5880, 5 mils thickness) and even low-cost discrete SMD components such as SOTA resistances (State Of The Art ^TM miniaturized surface mount resistors), which are modeled to be used well above commercial frequency margins. Intensive use of 3D EM simulation tools such as HFSS ^TM is done to support microstrip board modeling. Measurements of the three designs fabricated are compared to simulations and discussed. Full article

In this study, we present a novel type of package, freeform-designed chip scale package (FDCSP), which has ultra-high light extraction efficiency and bat-wing light field. For the backlight application, mainstream solutions are chip-scale package (CSP) and surface-mount device package (SMD). Comparing with these two mainstream types of package, the light extraction efficiency of CSP, SMD, and FDCSP are 88%, 60%, and 96%, respectively. In addition to ultra-high light extraction efficiency, because of the 160-degree bat-wing light field, FDCSP could provide a thinner and low power consumption mini-LED solution with a smaller number of LEDs than CSP and SMD light source array. Full article

We present a multisensor designed for industrial compressed air diagnostics and combining the measurement of pressure, flow, and temperature, integrated with the corresponding signal conditioning electronics in a single low-temperature co-fired ceramic (LTCC) package. The developed sensor may be soldered onto an integrated electro-fluidic platform by using standard surface mount device (SMD) technology, e.g., as a standard electronic component would be on a printed circuit board, obviating the need for both wires and tubes and thus paving the road towards low-cost integrated electro-fluidic systems. Several performance aspects of this device are presented and discussed, together with electronics design issues. Full article